Nested For loop not running full
Hello everyone, I have this part of my code where I am trying to traverse over an image by running a for loop for both x and y co-ordinate axis. But the loop is terminating by just reading first pixel. Can think of a reason why this is happening ? The code is: for sy in xrange(0, segimage.height): for sx in xrange(0, segimage.width): if segimage[sy,sx] == (0.0, 0.0, 0.0): continue else: seg_color = segimage[sy,sx] blue = int(seg_color[0]) green = int(seg_color[1]) red = int(seg_color[2]) reg_num = blue + 256 * green + 65536 * red for l in f: sp = l.split(,) if len(sp) == 14: print sy, sx # for checking which pixel its reading currently print reg_num, sp[0] # for checking whats happening if reg_num == int(sp[0].strip()): print reg_num, sp[0].strip() # for checking whats happening classification = int(sp[13].strip()) The inside for loop is for reading a csv format file from which I am extracting some information. Thanks in Advance for your suggestions -- http://mail.python.org/mailman/listinfo/python-list
Re: Nested For loop not running full
On Fri, Apr 26, 2013 at 2:39 PM, Peter Otten __pete...@web.de wrote: inshu chauhan wrote: I have this part of my code where I am trying to traverse over an image by running a for loop for both x and y co-ordinate axis. But the loop is terminating by just reading first pixel. Can think of a reason why this is happening ? The code is: for sy in xrange(0, segimage.height): for sx in xrange(0, segimage.width): if segimage[sy,sx] == (0.0, 0.0, 0.0): continue else: seg_color = segimage[sy,sx] blue = int(seg_color[0]) green = int(seg_color[1]) red = int(seg_color[2]) reg_num = blue + 256 * green + 65536 * red for l in f: sp = l.split(,) if len(sp) == 14: print sy, sx # for checking which pixel its reading currently print reg_num, sp[0] # for checking whats happening if reg_num == int(sp[0].strip()): print reg_num, sp[0].strip() # for checking whats happening classification = int(sp[13].strip()) The inside for loop is for reading a csv format file from which I am extracting some information. My crystal ball says that the 'for sy...' and 'for sx...' loops are running to completion, but you don't get the coordinates printed because you put them into the 'for l in f' loop which will only run once. Is there any means by which I can run this 'For l in f' loop again and again ? The quick and dirty fix is to replace f = open(...) in the code you are not showing with f == list(open(...)) f is just a text file(csv format).. so why list ?? The reasonable thing to do is of course to move the preprocessing (e.g. csv- parsing) out of the sy and sx loops. I did this but again then what I intend to do is not really happening, For every pixel I read, I want to traverse the full file, so that the information I am taking from pixel have to match in one of the line in the file. Can this be done by modifying my code ? or something new has to be devised ? -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: Nested For loop not running full
, 2013 at 3:15 PM, Chris Angelico ros...@gmail.com wrote: On Fri, Apr 26, 2013 at 7:36 PM, inshu chauhan insidesh...@gmail.com wrote: On Fri, Apr 26, 2013 at 2:39 PM, Peter Otten __pete...@web.de wrote: f = open(...) in the code you are not showing with f == list(open(...)) f is just a text file(csv format).. so why list ?? (That should be =, not ==) Instead of having an open file object, you would instead have a list of the lines in the file. That can be iterated over more than once. The reasonable thing to do is of course to move the preprocessing (e.g. csv- parsing) out of the sy and sx loops. I did this but again then what I intend to do is not really happening, For every pixel I read, I want to traverse the full file, so that the information I am taking from pixel have to match in one of the line in the file. Can this be done by modifying my code ? or something new has to be devised ? How large is the file? There are two easy solutions: 1) Open and close the file every time you touch a pixel 2) Open the file once, read it all into memory, and then iterate over the in-memory copy every pixel If your file is insanely large then the first option may be better, but for anything less than five yottabytes, go with the second. (Okay, I may be exaggerating slightly... let's say anything less than half your RAM. So if you have 10YB of memory, then I wasn't exaggerating.) That's why Peter suggested creating a list; you iterate over the list. Another way to do it is to parse the file once and retain a more efficient and useful structured form of the data... which is the other thing Peter suggested (move the preprocessing (e.g. csv- parsing) out of the sy and sx loops). So, yeah. Listen to Peter Otten, he knows what he's talking about :) ChrisA Yes I am trying Peter's way and my file is just 500 KB .. :) -- http://mail.python.org/mailman/listinfo/python-list
Running simultaneuos FOR loops
i have to implement the below line in one of my code: for p in sorted(segments.iterkeys()) and for k in sorted(class_count.iterkeys()) and for j in sorted(pixel_count.iterkeys()): Its giving me a syntax error which is obvious, but how can I make all three for loop run simultaneously or any other way to do this simultaneous work ??? -- http://mail.python.org/mailman/listinfo/python-list
Re: Running simultaneuos FOR loops
Yes Simultaneously means all three running at the same time, I looked up zip just now, but will it not disturb my dictionaries ? And yes the dictionaries have same number of keys. thanks On Tue, Apr 23, 2013 at 12:16 PM, Chris Angelico ros...@gmail.com wrote: On Tue, Apr 23, 2013 at 4:40 PM, inshu chauhan insidesh...@gmail.com wrote: i have to implement the below line in one of my code: for p in sorted(segments.iterkeys()) and for k in sorted(class_count.iterkeys()) and for j in sorted(pixel_count.iterkeys()): Its giving me a syntax error which is obvious, but how can I make all three for loop run simultaneously or any other way to do this simultaneous work ??? Define simultaneously. Do the three dictionaries have the same number of keys? If so, look up zip() or itertools.izip; if not, you may have to more clearly define simultaneous. ChrisA -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: Running simultaneuos FOR loops
zip isn't doing the required On Tue, Apr 23, 2013 at 12:28 PM, inshu chauhan insidesh...@gmail.comwrote: Yes Simultaneously means all three running at the same time, I looked up zip just now, but will it not disturb my dictionaries ? And yes the dictionaries have same number of keys. thanks On Tue, Apr 23, 2013 at 12:16 PM, Chris Angelico ros...@gmail.com wrote: On Tue, Apr 23, 2013 at 4:40 PM, inshu chauhan insidesh...@gmail.com wrote: i have to implement the below line in one of my code: for p in sorted(segments.iterkeys()) and for k in sorted(class_count.iterkeys()) and for j in sorted(pixel_count.iterkeys()): Its giving me a syntax error which is obvious, but how can I make all three for loop run simultaneously or any other way to do this simultaneous work ??? Define simultaneously. Do the three dictionaries have the same number of keys? If so, look up zip() or itertools.izip; if not, you may have to more clearly define simultaneous. ChrisA -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: Running simultaneuos FOR loops
Thanks Gary. Be clearer about the problem please. Do you wish to produce a loop that: On pass 1, each of p,k, and t hold the first item of their respective lists, and on pass 2, each of p,k, and t hold the second item of their respective lists, and so on until one (or all) lists run out? Yes this is excatly what I want each loop holds the first item on each pass. If that is what you want, then check out the zip builtin function. But also consider this: Do you care what happens if one list runs out before the others? Yes, but all dictionaries have same number of items. Or is it something else you want? Perhaps nested loops? for p in sorted(segments.iterkeys()): for k in sorted(class_count.iterkeys()): for j in sorted(pixel_count.iterkeys()): # This will be run with all possible combinations of p,k, and t No, I know about nested loops but I dont want that because all the loops have same number of items, inner loops will run out earlier. Gary Herron -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: Running simultaneuos FOR loops
This statement is giving me the following error Statement: for p, k, j in zip(sorted(segments.iterkeys(), class_count.iterkeys(), pixel_count.iterkeys())): Error: Traceback (most recent call last): File C:\Users\inshu\Desktop\Training_segs_trial2.py, line 170, in module access_segments(segimage, data) File C:\Users\inshu\Desktop\Training_segs_trial2.py, line 147, in access_segments for p, k, j in zip(sorted(segments.iterkeys(), class_count.iterkeys(), pixel_count.iterkeys())): TypeError: 'dictionary-keyiterator' object is not callable On Tue, Apr 23, 2013 at 12:33 PM, inshu chauhan insidesh...@gmail.comwrote: zip isn't doing the required On Tue, Apr 23, 2013 at 12:28 PM, inshu chauhan insidesh...@gmail.comwrote: Yes Simultaneously means all three running at the same time, I looked up zip just now, but will it not disturb my dictionaries ? And yes the dictionaries have same number of keys. thanks On Tue, Apr 23, 2013 at 12:16 PM, Chris Angelico ros...@gmail.comwrote: On Tue, Apr 23, 2013 at 4:40 PM, inshu chauhan insidesh...@gmail.com wrote: i have to implement the below line in one of my code: for p in sorted(segments.iterkeys()) and for k in sorted(class_count.iterkeys()) and for j in sorted(pixel_count.iterkeys()): Its giving me a syntax error which is obvious, but how can I make all three for loop run simultaneously or any other way to do this simultaneous work ??? Define simultaneously. Do the three dictionaries have the same number of keys? If so, look up zip() or itertools.izip; if not, you may have to more clearly define simultaneous. ChrisA -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Working with lists within Dictionaries
Hello Everyone,
I am trying to work with lists and dictionaries together.
In the following code I have to access pixels in a segmented image through
a dictionary. But the problem is when I am trying to update the list
through dict it is giving me this error of tuple, ofcourse because list
indices should be integer.
THE CODE IS :
import cv
def access_segments(segimage, data):
print segimage
segments = {}
for y in xrange(0, segimage.height):
for x in xrange(0, segimage.width):
if segimage[y,x] == (0.0, 0.0, 0.0):
continue
else:
seg_color = segimage[y,x]
blue = int(seg_color[0])
green = int(seg_color[1])
red = int(seg_color[2])
reg_num = blue + 256 * green + 65536 * red
point = data[y,x]
segments.setdefault(reg_num, [])[point] += point
for p in sorted(segments.iterkeys()):
points = (segments[p])
print len(points)
print points
if __name__== __main__:
data = cv.Load(rC:\Users\inshu\Desktop\Masters
Thesis\data\xyz_0.yml)
segimage = cv.LoadImageM(rC:\Users\inshu\Desktop\Masters
Thesis\Segmentation\segmentation_numbers_0.tif,
cv.CV_LOAD_IMAGE_UNCHANGED)
access_segments(segimage, data)
THE ERROR IS:
cvmat(type=42424010 8UC3 rows=3000 cols=3000 step=9000 )
Traceback (most recent call last):
File C:\Users\inshu\Desktop\test_reading .py, line 27, in module
access_segments(segimage, data)
File C:\Users\inshu\Desktop\test_reading .py, line 16, in
access_segments
segments.setdefault(reg_num, [])[point] += point
TypeError: list indices must be integers, not tuple
How can I access the data without getting this error ? the points have x,
y, z co-ordinates.
Thanks In Advance for your suggestions.
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Can I iterate over a dictionary outside a function ?
I have a prog in which a functions returns a dict but when I try to iterate over the dict using iterkeys, It shows an error. I think its because only address of the dictionary is returned so cannot be iterated upon. Please suggest some way by which it can be made possible to iterate over the dictionary using iterkeys outside the function ? -- http://mail.python.org/mailman/listinfo/python-list
Trying to understand working with dicts
Hello everyone, Here in my part of the code where cc is a dictionary. I want to understand what actually cc.iterkeys() and cc[k] actually doing. I am already reading http://docs.python.org/2/library/stdtypes.html#dict.items and http://www.tutorialspoint.com/python/python_dictionary.htm but still not very clear. cc = Computesegclass(segimage, refimage) for k in sorted(cc.iterkeys()): i = argmax(cc[k]) print f, i+1 Thanks in Advance -- http://mail.python.org/mailman/listinfo/python-list
Error in working with Dict
I have this program which is working with 2 dictionaries segments,
class_counts.. but I am getting an error mentioned below the programme.
import cv
from itertools import *
from math import floor, sqrt, ceil
from numpy import array, dot, subtract, add, outer, argmax, linalg as lin
def Computesegclass(segimage, refimage):
f = open(Pixel_count_with_region_num_trial1.txt, w)
segments = {}
class_count = {}
for y in xrange(0, segimage.height):
for x in xrange(0, segimage.width):
if segimage[y,x] == (0.0, 0.0, 0.0):
continue
else:
seg_color = segimage[y,x]
blue = int(seg_color[0])
green = int(seg_color[1])
red = int(seg_color[2])
region_num = blue + 256 * green + 65536 * red
#print region_num
segments[region_num] = segments.setdefault(region_num, 0) +
1
#print segments
class_color = refimage[y,x]
if class_color == (0.0,0.0,0.0):
class_number = 0 # No class
elif class_color == (0.0,255.0,0.0):
class_number = 1 # Trees
elif class_color == (255.0, 0.0, 128.0):
class_number = 2 # Buildings
elif class_color == (0.0,0.0,255.0):
class_number = 3# Automobiles
elif class_color == (255.0, 255.0, 0.0):
class_number = 4# Road Points
elif class_color == (0.0, 64.0, 128.0):
class_number = 5# Tree trunks nad branches
elif class_color == (255.0, 0.0 ,0.0):
class_number = 6# Poles
elif class_color == (255.0, 0.0, 255.0):
class_number = 7# Traffic Lights
else:
class_number = 0 # Gray Pixel
class_count.setdefault(region_num, [0, 0, 0, 0, 0, 0, 0,
0])[class_number] += 1
# print class_count
for k in sorted(class_count.iterkeys()):
i = argmax(class_count[k])
print f, i
if __name__== __main__:
segimage = cv.LoadImageM(rC:\Users\inshu\Desktop\Masters
Thesis\Segmentation\segmentation_numbers_0.tif,
cv.CV_LOAD_IMAGE_UNCHANGED)
refimage = cv.LoadImageM(rC:\Users\inshu\Desktop\Masters
Thesis\Segmentation\Hand_Classified1.tif, cv.CV_LOAD_IMAGE_UNCHANGED)
print segimage
Computesegclass(segimage, refimage)
ERROR :
Traceback (most recent call last):
File C:\Users\inshu\Desktop\seg.py, line 49, in module
for k in sorted(class_count.iterkeys()):
NameError: name 'class_count' is not defined
I know this error is because I have initialized both dicts inside the
function, But why dicts are not saved out, if I intialize the dicts outside
the function, the processing is still done inside and end result I am
getting is an empty dict.
Thanks in Advance for suggestions
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working with dict : incrementing dict dynamically
I am trying to create a dictionary with a key and its values seraching from
a data set. But something is going wrong. This is the first time I am
working with dicts.
My code is :
import cv
def Computesegclass(segimage):
num_pixel = 0
for y in xrange(0, segimage.height):
for x in xrange(0, segimage.width):
if segimage[y,x] == (0.0, 0.0, 0.0):
continue
else:
color = segimage[y,x]
blue = color[0]
green = color[1]
red = color[2]
region_num = blue + 256 * green + 65536 * red
print region_num
segments = dict({region_num : num_pixel})
if region_num == region_num:
num_pixel = +1
print segments
if __name__== __main__:
segimage =
cv.LoadImageM(Z:/Segmentation/segmentation_numbers_0.tif,
cv.CV_LOAD_IMAGE_UNCHANGED)
print segimage
Computesegclass(segimage)
here I am traversing through an image which is 3000 x 3000. for each pixel
I calculate a region number. What I am trying to do is increase the
num_pixel by 1 if that pixel falls in the same region which is identified
by region_num. How can I do it in dict created ?
Thanx in Advance
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working with csv module in python
I have 10 simple text files with 3 columns x,y,z delimited by space. I am trying to combine these 10 files to get a single text file. Eg. of data in 10 files is 299 446 2 I had written this prog for merging files: import csv import glob with open(rC:\Users\inshu.chauhan\Desktop\test2.arff, w) as w: writer = csv.writer(w, delimiter = ' ', quotechar = ' ' ,quoting = csv.QUOTE_MINIMAL) for f in glob.glob(rC:\Users\inshu.chauhan\Desktop\For Model_600\*.arff): rows = open(f, r).readlines() writer.writerows(rows) But the result after merging the files is not I need , it is something like : 2 9 9 4 4 6 2 2 9 9 4 4 7 2 2 9 9 4 4 8 2 2 9 8 4 4 9 2 Can in some some way I set delimiter to NULL as the prog gives me error if I do so. I dont why there is space between the attribute of first column in reading and there is space between every row too.. Or can I merge these text files without using csv module , directly in python ? Looking forward to your suggestions. Thanks in advance !!! -- http://mail.python.org/mailman/listinfo/python-list
Re: working with csv module in python
On Wed, Feb 20, 2013 at 11:26 AM, Roland Koebler r.koeb...@yahoo.de wrote: Hi, On Wed, Feb 20, 2013 at 10:50:54AM +0100, inshu chauhan wrote: I have 10 simple text files with 3 columns x,y,z delimited by space. I am trying to combine these 10 files to get a single text file. Eg. of data in 10 files is 299 446 2 Do you only want to concat the files, or do you want to parse/mangle them? If you only want to concat the files, I would use some shell-tools, like cat on Linux or copy on Windows, so copy C:\Users\inshu.chauhan\Desktop\ForModel_600\*.arff C:\Users\inshu.chauhan\Desktop\test2.arff should do it. Can in some some way I set delimiter to NULL as the prog gives me error if I do so. Of course -- a CSV without a delimiter doesn't make any sense. I dont why there is space between the attribute of first column in reading and there is space between every row too.. Because there's a split() missing in your code. You currently tell the CSV-writer to write the columns 2,9,9, , , ,4,4,6, , , ,2 as space-separated CSV. So, try something like rows = [r.split() for r in open(f, r).readlines()] Or can I merge these text files without using csv module , directly in python ? If you don't need to parse/mangle the contents, you don't need the csv module. Simple open the resulting file for writing, and then read out the source files and write their contents into the resulting file. Yes I just want to concat the files , not parse/mangle the files. How can i simply read all files in a folder in my computer and write them into a single file ? just by 'printf ' is it possible ? -- http://mail.python.org/mailman/listinfo/python-list
Re: working with csv module in python
On Wed, Feb 20, 2013 at 11:38 AM, inshu chauhan insidesh...@gmail.comwrote: On Wed, Feb 20, 2013 at 11:26 AM, Roland Koebler r.koeb...@yahoo.dewrote: Hi, On Wed, Feb 20, 2013 at 10:50:54AM +0100, inshu chauhan wrote: I have 10 simple text files with 3 columns x,y,z delimited by space. I am trying to combine these 10 files to get a single text file. Eg. of data in 10 files is 299 446 2 Do you only want to concat the files, or do you want to parse/mangle them? If you only want to concat the files, I would use some shell-tools, like cat on Linux or copy on Windows, so copy C:\Users\inshu.chauhan\Desktop\ForModel_600\*.arff C:\Users\inshu.chauhan\Desktop\test2.arff should do it. Can in some some way I set delimiter to NULL as the prog gives me error if I do so. Of course -- a CSV without a delimiter doesn't make any sense. I dont why there is space between the attribute of first column in reading and there is space between every row too.. Because there's a split() missing in your code. You currently tell the CSV-writer to write the columns 2,9,9, , , ,4,4,6, , , ,2 as space-separated CSV. So, try something like rows = [r.split() for r in open(f, r).readlines()] Or can I merge these text files without using csv module , directly in python ? If you don't need to parse/mangle the contents, you don't need the csv module. Simple open the resulting file for writing, and then read out the source files and write their contents into the resulting file. Yes I just want to concat the files , not parse/mangle the files. How can i simply read all files in a folder in my computer and write them into a single file ? just by 'printf ' is it possible ? For simple concating the files , I tried the following code : import glob with open(rC:\Users\inshu.chauhan\Desktop\test2.arff, w) as w: print w for f in glob.glob(rC:\Users\inshu.chauhan\Desktop\For Model_600\*.arff): g = f.read() w.write(g) But I think I am having an obvious error : open file 'C:\Users\inshu.chauhan\Desktop\test2.arff', mode 'w' at 0x01B64F40 Traceback (most recent call last): File C:\Users\inshu.chauhan\Desktop\Concatfiles.py, line 6, in module g = f.read() AttributeError: 'str' object has no attribute 'read' Here I am trying to refer the files stored in my folder by 'f', Why read() is not working ? -- http://mail.python.org/mailman/listinfo/python-list
Re: working with csv module in python
On Wed, Feb 20, 2013 at 12:04 PM, Dave Angel da...@davea.name wrote: On 02/20/2013 05:38 AM, inshu chauhan wrote: On Wed, Feb 20, 2013 at 11:26 AM, Roland Koebler r.koeb...@yahoo.de wrote: snip If you only want to concat the files, I would use some shell-tools, like cat on Linux or copy on Windows, so copy C:\Users\inshu.chauhan\**Desktop\ForModel_600\*.arff C:\Users\inshu.chauhan\**Desktop\test2.arff should do it. snip Yes I just want to concat the files , not parse/mangle the files. How can i simply read all files in a folder in my computer and write them into a single file ? just by 'printf ' is it possible ? Reread Roland's message, quoted above for your convenience. Not sure what you mean by printf. Why would you use C to do it? If you need to do it in Python, remember you can read a file with the read() method, and write one with the write() method. They pay no attention to newlines, delimiters or anything else. Just create the output file, then in a loop open the input files and loop through each (read doesn't necessarily get the whole thing in one pass) You'll spend lots more energy on the mechanics of finding the files then on the copying. But perhaps the shutil module will have some further shortcuts. -- DaveA -- http://mail.python.org/**mailman/listinfo/python-listhttp://mail.python.org/mailman/listinfo/python-list You are right Dave, printf was a blunder -- http://mail.python.org/mailman/listinfo/python-list
IOerror : need urgent help
Here is my attempt to merge 10 files stored in a folder into a single file :
import csv
with open(C:\Users\inshu.chauhan\Desktop\test.arff, w) as w:
writer = csv.writer(w)
for f in glob.glob(C:\Users\inshu.chauhan\Desktop\For
Model_600\*.arff):
rows = open(f, r).readlines()
writer.writerows(rows)
Error:
Traceback (most recent call last):
File C:\Users\inshu.chauhan\Desktop\Mergefiles.py, line 3, in module
with open(C:\Users\inshu.chauhan\Desktop\test.arff, w) as w:
IOError: [Errno 22] invalid mode ('w') or filename:
'C:\\Users\\inshu.chauhan\\Desktop\test.arff'
Why my programme is not working ?? :(
Thanks in Advance !!
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Re: IOerror : need urgent help
On Tue, Feb 19, 2013 at 4:54 PM, MRAB pyt...@mrabarnett.plus.com wrote:
On 2013-02-19 15:27, inshu chauhan wrote:
Here is my attempt to merge 10 files stored in a folder into a single
file :
import csv
with open(C:\Users\inshu.chauhan\**Desktop\test.arff, w) as w:
writer = csv.writer(w)
for f in glob.glob(C:\Users\inshu.**chauhan\Desktop\For
Model_600\*.arff):
rows = open(f, r).readlines()
writer.writerows(rows)
Error:
Traceback (most recent call last):
File C:\Users\inshu.chauhan\**Desktop\Mergefiles.py, line 3, in
module
with open(C:\Users\inshu.chauhan\**Desktop\test.arff, w) as w:
IOError: [Errno 22] invalid mode ('w') or filename:
'C:\\Users\\inshu.chauhan\\**Desktop\test.arff'
Why my programme is not working ?? :(
Look at the traceback. It says that the path is:
'C:\\Users\\inshu.chauhan\\**Desktop\test.arff'
All but one of the backslashes are doubled.
That's because the backslash character \ starts an escape sequence, but
if it can't recognise the escape sequence, it treats the backslash as a
literal character.
In that string literal, '\t' is an escape sequence representing a tab
character (it's equal to chr(9)), but '\U', '\i' and '\D' are not
escape sequences, so they are equivalent to '\\U, '\\i' and '\\D'
respectively.
What you should do is use raw string literals for paths:
rC:\Users\inshu.chauhan\**Desktop\test.arff
or use '/' instead (Windows allows it as an alternative, unless it
occurs initially, which you'll rarely want to do in practice):
C:/Users/inshu.chauhan/**Desktop/test.arff
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Thanks I understood the problem now and my programme is working !!
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Error in reading and writing CSV format file in python
In the programme below I am trying to read two csv format files and process them and write a new file with some of theirs data. import csv f1_reader = csv.reader(open(rZ:\Weka work\Feature_Vectors_Fullset_00.arff)) f2_reader = csv.reader(open(rZ:\Weka work\Feature_Vectors_Fullset_00_noxy+class.arff)) nf = open(rZ:\Weka work\classified_image00_withoutxy.arff, w) while True: l1 = f1_reader.next() while len(l1) != 12: l1 = f1_reader.next() l2 = f2_reader.next() while len(l2) != 11: l2 = f2_reader.next() ix = l1[0].strip() iy = l1[1].strip() classification = l2[8].strip() print nf, ix, iy, classification nf.close() This programme is giving me this error now : Traceback (most recent call last): File Z:\Weka work\final_image_classificationwithoutxy.py, line 16, in module l2 = f2_reader.next() StopIteration what could be a possible reason to StopIteration ??? I checked the syntax and usage of this module looks alright to me , but then why this error ? Thankyou in Advance -- http://mail.python.org/mailman/listinfo/python-list
Re: Error in reading and writing CSV format file in python
On Mon, Feb 11, 2013 at 1:26 PM, Steven D'Aprano steve+comp.lang.pyt...@pearwood.info wrote: inshu chauhan wrote: In the programme below I am trying to read two csv format files and process them and write a new file with some of theirs data. import csv f1_reader = csv.reader(open(rZ:\Weka work\Feature_Vectors_Fullset_00.arff)) f2_reader = csv.reader(open(rZ:\Weka work\Feature_Vectors_Fullset_00_noxy+class.arff)) nf = open(rZ:\Weka work\classified_image00_withoutxy.arff, w) while True: l1 = f1_reader.next() while len(l1) != 12: l1 = f1_reader.next() l2 = f2_reader.next() while len(l2) != 11: l2 = f2_reader.next() ix = l1[0].strip() iy = l1[1].strip() classification = l2[8].strip() print nf, ix, iy, classification nf.close() This programme is giving me this error now : Traceback (most recent call last): File Z:\Weka work\final_image_classificationwithoutxy.py, line 16, in module l2 = f2_reader.next() StopIteration what could be a possible reason to StopIteration ??? next() raises StopIteration when there is nothing else to return. py it = iter([1, 2, 3]) py it.next() 1 py it.next() 2 py it.next() 3 py it.next() Traceback (most recent call last): File stdin, line 1, in module StopIteration You have reached the end of the file and there is nothing else for the CSV reader to return, so it raises StopIteration. But why does it has nothing to return so early before traversing the whole file ? Is there any way it can be corrected ? And also the programme isn't writing anything to the file ? -- http://mail.python.org/mailman/listinfo/python-list
Re: Error in reading and writing CSV format file in python
On Mon, Feb 11, 2013 at 2:02 PM, MRAB pyt...@mrabarnett.plus.com wrote: On 2013-02-11 12:44, inshu chauhan wrote: On Mon, Feb 11, 2013 at 1:26 PM, Steven D'Aprano steve+comp.lang.python@**pearwood.infosteve%2bcomp.lang.pyt...@pearwood.info mailto:steve+comp.lang.**pyt...@pearwood.infosteve%2bcomp.lang.pyt...@pearwood.info wrote: inshu chauhan wrote: In the programme below I am trying to read two csv format files and process them and write a new file with some of theirs data. import csv f1_reader = csv.reader(open(rZ:\Weka work\Feature_Vectors_Fullset_**00.arff)) f2_reader = csv.reader(open(rZ:\Weka work\Feature_Vectors_Fullset_**00_noxy+class.arff)) nf = open(rZ:\Weka work\classified_image00_**withoutxy.arff, w) while True: l1 = f1_reader.next() while len(l1) != 12: l1 = f1_reader.next() l2 = f2_reader.next() while len(l2) != 11: l2 = f2_reader.next() ix = l1[0].strip() iy = l1[1].strip() classification = l2[8].strip() print nf, ix, iy, classification nf.close() This programme is giving me this error now : Traceback (most recent call last): File Z:\Weka work\final_image_**classificationwithoutxy.py, line 16, in module l2 = f2_reader.next() StopIteration what could be a possible reason to StopIteration ??? next() raises StopIteration when there is nothing else to return. py it = iter([1, 2, 3]) py it.next() 1 py it.next() 2 py it.next() 3 py it.next() Traceback (most recent call last): File stdin, line 1, in module StopIteration You have reached the end of the file and there is nothing else for the CSV reader to return, so it raises StopIteration. But why does it has nothing to return so early before traversing the whole file ? Is there any way it can be corrected ? And also the programme isn't writing anything to the file ? Try adding some logging so that you can see what it's doing. A simple way would be something like: log_file = open(rZ:\Weka work\log.txt, w) ... l1 = f1_reader.next() print log_file, Read from f1:, l1 print log_file, Length is, len(l1) while len(l1) != 12: l1 = f1_reader.next() print log_file, Read from f1:, l1 print log_file, Length is, len(l1) and so on. -- http://mail.python.org/**mailman/listinfo/python-listhttp://mail.python.org/mailman/listinfo/python-list Thanks :) This worked !!! -- http://mail.python.org/mailman/listinfo/python-list
Re: Error in reading and writing CSV format file in python
On Mon, Feb 11, 2013 at 3:22 PM, Dave Angel da...@davea.name wrote: On 02/11/2013 06:00 AM, inshu chauhan wrote: In the programme below I am trying to read two csv format files and process them and write a new file with some of theirs data. import csv f1_reader = csv.reader(open(rZ:\Weka work\Feature_Vectors_Fullset_**00.arff)) f2_reader = csv.reader(open(rZ:\Weka work\Feature_Vectors_Fullset_**00_noxy+class.arff)) nf = open(rZ:\Weka work\classified_image00_**withoutxy.arff, w) while True: l1 = f1_reader.next() while len(l1) != 12: l1 = f1_reader.next() l2 = f2_reader.next() while len(l2) != 11: l2 = f2_reader.next() ix = l1[0].strip() iy = l1[1].strip() classification = l2[8].strip() print nf, ix, iy, classification nf.close() This programme is giving me this error now : Traceback (most recent call last): File Z:\Weka work\final_image_**classificationwithoutxy.py, line 16, in module l2 = f2_reader.next() StopIteration what could be a possible reason to StopIteration ??? I checked the syntax and usage of this module looks alright to me , but then why this error ? That's not an error, it's just a normal way to end a for-loop. If you were using a syntax like: for item in f2_reader: the StopIteration would simply end the loop. Since you're doing it manually, you have to handle the exception yourself. -- DaveA -- http://mail.python.org/**mailman/listinfo/python-listhttp://mail.python.org/mailman/listinfo/python-list Yes , therefore I used try and except. -- http://mail.python.org/mailman/listinfo/python-list
Run time Error
Hello all, I am trying to run a small code of mine but I am getting a run time error. What is actually meant by run time error ? it is saying to contact programme administrator something. Why one would get this error ? and how to remove it ? -- http://mail.python.org/mailman/listinfo/python-list
Re: Run time Error
On Tue, Feb 5, 2013 at 3:10 PM, Roy Smith r...@panix.com wrote: In article mailman.1366.1360073151.2939.python-l...@python.org, inshu chauhan insidesh...@gmail.com wrote: Hello all, I am trying to run a small code of mine but I am getting a run time error. What is actually meant by run time error ? it is saying to contact programme administrator something. Why one would get this error ? and how to remove it ? Start by telling us: 1) What code you are running (copy-paste the exact source code). 2) What error message you got (likewise, copy-paste the exact message). 3) What version of Python you're running. 4) What system and version you're running it on (Linux, OSX, Windows, etc). -- http://mail.python.org/mailman/listinfo/python-list Thans to all.. but I resolved the problem :) -- http://mail.python.org/mailman/listinfo/python-list
Re: Reading data from 2 different files and writing to a single file
On Mon, Jan 28, 2013 at 6:05 PM, Dennis Lee Bieber wlfr...@ix.netcom.comwrote: On Mon, 28 Jan 2013 14:31:31 +0100, inshu chauhan insidesh...@gmail.com declaimed the following in gmane.comp.python.general: In the code below I am trying to read 2 files f1 and f2 , extract some data from them and then trying to write them into a single file that is 'nf'. import cv f1 = open(rZ:\modules\Feature_Vectors_300.arff) f2 = open(rZ:\modules\Feature_Vectors_300_Pclass.arff) nf = open(rZ:\modules\trial.arff, w) for l in f1: sp = l.split(,) If you are going to be splitting on commas, you might want to read up on the csv (comma separate values) module The csv module has many fuctions but not of much use to me and it makes my programme slower if len(sp)!= 12: continue else: Given the apparent block structure, you could drop the continue/else, and more cleanly just use Yeah, Thats Right if len(sp) == 12: ix = sp[0].strip() iy = sp[1].strip() print ix, iy for s in f2: It's been mentioned that the indentation is wrong here I dont know why the indentation is wrong ? st = s.split(,) csv module again if len(st)!= 11: continue else: I'm tempted to repeat the comment on reversing the conditional BUT clas = st[10].strip() print ix, iy, clas print nf, ix, iy, clas The indentation of the print statements is not aligned with the previous assignment -- the effect is the same however as everything under the else is executed anyway. But as has also been mentioned, ignoring indentation, the apparent algorithm you have here is going to process every line of f2 for the first line of f1 -- and then for later lines in f1 it will find f2 is at the end of file, and do nothing. If it is supposed to process every line of f2 for each line of f1, you'll need to rewind f2. For that I added 'Break' statement as suggested by Chris in above mails. If you mean to match one line of f1 with one line of f2, you do not want nested loops. But now you have to define the behavior if one of the two files is correct length and the other is not? Do you skip both or read the next line from the wrong length file? And how will you handle files with different numbers of records. Yes , actually my Prog was like this : for l in f1: sp = l.split(,) if len(sp)!= 12: continue else: ix = sp[0].strip() iy = sp[1].strip() for s in f2: st = s.split(,) if len(st)!= 11: continue else: clas = st[10].strip() print ix, iy, clas print nf, ix, iy, clas break f1.close() f2.close() nf.close() I actually dont want nested loops but cant find another way to achieve what I want, But for these files I am sure that they have equal lengths, thats why I am taking the risk of using nested loops.. Can you suggest any different way to go around this problem , which could be flexible and non-errorneous ? -- Wulfraed Dennis Lee Bieber AF6VN wlfr...@ix.netcom.comHTTP://wlfraed.home.netcom.com/ -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: Reading data from 2 different files and writing to a single file
On Wed, Jan 30, 2013 at 2:23 PM, Dave Angel d...@davea.name wrote: On 01/30/2013 05:43 AM, inshu chauhan wrote: On Mon, Jan 28, 2013 at 6:05 PM, Dennis Lee Bieber wlfr...@ix.netcom.com wrote: On Mon, 28 Jan 2013 14:31:31 +0100, inshu chauhan insidesh...@gmail.com declaimed the following in gmane.comp.python.general: In the code below I am trying to read 2 files f1 and f2 , extract some data from them and then trying to write them into a single file that is 'nf'. import cv f1 = open(rZ:\modules\Feature_**Vectors_300.arff) f2 = open(rZ:\modules\Feature_**Vectors_300_Pclass.arff) nf = open(rZ:\modules\trial.arff, w) for l in f1: sp = l.split(,) If you are going to be splitting on commas, you might want to read up on the csv (comma separate values) module The csv module has many fuctions but not of much use to me and it makes my programme slower if len(sp)!= 12: continue else: Given the apparent block structure, you could drop the continue/else, and more cleanly just use Yeah, Thats Right if len(sp) == 12: ix = sp[0].strip() iy = sp[1].strip() print ix, iy for s in f2: It's been mentioned that the indentation is wrong here I dont know why the indentation is wrong ? Your for statement is not lined up with the print that precedes it. If your code were really that way, you'd be getting an indentation error. So we assume it's because your email editor is mangling the code. Post in text email, not in html. st = s.split(,) csv module again if len(st)!= 11: continue else: I'm tempted to repeat the comment on reversing the conditional BUT clas = st[10].strip() print ix, iy, clas print nf, ix, iy, clas The indentation of the print statements is not aligned with the previous assignment -- the effect is the same however as everything under the else is executed anyway. But as has also been mentioned, ignoring indentation, the apparent algorithm you have here is going to process every line of f2 for the first line of f1 -- and then for later lines in f1 it will find f2 is at the end of file, and do nothing. If it is supposed to process every line of f2 for each line of f1, you'll need to rewind f2. For that I added 'Break' statement as suggested by Chris in above mails. If you mean to match one line of f1 with one line of f2, you do not want nested loops. But now you have to define the behavior if one of the two files is correct length and the other is not? Do you skip both or read the next line from the wrong length file? And how will you handle files with different numbers of records. Yes , actually my Prog was like this : for l in f1: sp = l.split(,) if len(sp)!= 12: continue else: ix = sp[0].strip() iy = sp[1].strip() for s in f2: This is not nested, it's back at the left margin. Or it could be posting wrong because you're still posting in html, instead of plain text email. Yes My Initial code was not nested at the same time of no use too, I am trying to use zip() now :) :) nyways.. st = s.split(,) if len(st)!= 11: continue else: clas = st[10].strip() print ix, iy, clas print nf, ix, iy, clas break f1.close() f2.close() nf.close() I actually dont want nested loops but cant find another way to achieve what I want, But for these files I am sure that they have equal lengths, thats why I am taking the risk of using nested loops. You have that backwards. Because you say you can assume they're the same length, you don't need the flexibility (and unreadability) of the nested approach. The zip approach works great, and nested is unnecessary. . Can you suggest any different way to go around this problem , which could be flexible and non-errorneous ? -- http://mail.python.org/mailman/listinfo/python-list
Reading data from 2 different files and writing to a single file
In the code below I am trying to read 2 files f1 and f2 , extract some data from them and then trying to write them into a single file that is 'nf'. import cv f1 = open(rZ:\modules\Feature_Vectors_300.arff) f2 = open(rZ:\modules\Feature_Vectors_300_Pclass.arff) nf = open(rZ:\modules\trial.arff, w) for l in f1: sp = l.split(,) if len(sp)!= 12: continue else: ix = sp[0].strip() iy = sp[1].strip() print ix, iy for s in f2: st = s.split(,) if len(st)!= 11: continue else: clas = st[10].strip() print ix, iy, clas print nf, ix, iy, clas f1.close() f2.close() nf.close() I think my code is not so correct , as I am not getting desired results and logically it follows also but I am stuck , cannot find a way around this simple problem of writing to a same file.. Please suggest some good pythonic way I can do it.. Thanks in Advance -- http://mail.python.org/mailman/listinfo/python-list
Re: Reading data from 2 different files and writing to a single file
Yes Chris, I understand, My Original code was for l in f1: sp = l.split(,) if len(sp)!= 12: continue else: ix = sp[0].strip() iy = sp[1].strip() for s in f2: st = s.split(,) if len(st)!= 11: continue else: clas = st[10].strip() print ix, iy, clas print nf, ix, iy, clas f1.close() f2.close() nf.close() where f1 contains something like : 297, 404, , 298, 404, , .. 299, 404, . . .. 295, 452, and f2 contains something like : 7 . 2 2 .7 and what I want to be written in the new file i.e. nf is something like: 297 404 7 297 404 7 297 404 7 297 404 7 297 404 7 297 404 7 297 404 7 297 404 7 297 404 7 297 404 7 297 404 7 297 404 7 297 404 7 297 404 7 297 404 2 297 404 2 297 404 2 297 404 2 297 404 2 which m getting but partially correct because only last value is changing not the first two... which should not happen.. In every loop all the three values should change.. -- http://mail.python.org/mailman/listinfo/python-list
Re: Reading data from 2 different files and writing to a single file
In that case, Dave's suggestion to read into a list and iterate over the list is to be strongly considered. But I'm not entirely sure what your goal is here. Are you trying to make the Cartesian product of the two files, where you have one line in the output for each possible pair of matching lines? That is, for each line in the first file, you make a line in the output for each line in the second? That's what your code will currently do. No , I dont want that , actually both files have equal no of lines, I want to read the first line of f1 , take 2 datas from it, nd then read first line of f2, take data from it, then print them to the same first line of new file i.e nf. ChrisA -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: Reading data from 2 different files and writing to a single file
Your current logic tries to scan through the first file, and for each line that has 12 elements, scans through the entire second file. It fails to actually do it, because you never do a seek on the second file. Now it appears your requirement is entirely different. I believe you have two text files each having the same number of lines. You want to loop through the pair of lines (once from each file, doing some kind of processing and printing). If that's the case, your nested loop is the wrong thing, and you can forget my caveat about nesting file reads. What you want is the zip() function for l,s in zip(f1, f2): #you now have one line from each file, # which you can then validate and process Note, this assumes that when a line is bad from either file, you're going to also ignore the corresponding line from the other. If you have to accommodate variable misses in the lining up, then your work is *much* harder. Actually these are Arff files used in Weka (Data Mining ), So they have a certain amount of header information which is the same in both files(in same no. of lines too ) and both files have equal lines, So when I read basically In both files I am trying to ignore the Header information. then it is like reading first line from f1 and first line from f2, extracting the data I want from each file and simply write it to a third file line by line... What does actually Zip function do ? Thanks and Regards -- http://mail.python.org/mailman/listinfo/python-list
Re: Reading data from 2 different files and writing to a single file
That's zip not Zip Have you tried looking at the docs? Or even typing help(zip) at the python interpreter prompt? In rough terms, zip takes one element (line) from each of the iterators, and creates a new list that holds tuples of those elements. If you use it in this form: for item1, item2 in zip(iter1, iter2): then item1 will be the first item of iter1, and item2 will be the first item of iter2. You then process them, and loop around. It stops when either iterator runs out of items. https://duckduckgo.com/?q=**python+ziphttps://duckduckgo.com/?q=python+zip gives me http://docs.python.org/2/**library/functions.html#ziphttp://docs.python.org/2/library/functions.html#zip as the first link. This will read the entire content of both files into the list, so if they are more than 100meg or so, you might want to use izip(). (In Python3.x, zip will do what izip does on Python 2.x) -- DaveA -- http://mail.python.org/**mailman/listinfo/python-listhttp://mail.python.org/mailman/listinfo/python-list Thanks Dave, I am Sorry , true I dint look up for it because as per the Suggetion by Chris, 'break' does solve my problem but I wanted to know a little about 'zip' for I encounter any other problem, parsing these two files. -- http://mail.python.org/mailman/listinfo/python-list
using split for a string : error
Here I have a code which basically reads a csv file, tries to compare the last 2 items in each line of the file. f = open(rZ:\modules\Feature_Vectors_300_Pclass.arff) for l in f: sp = l.split(,) if len(sp) != 11: print of, l, else: #print sp[9], sp[10] if sp[9] == sp[10]: print Same class else : print Different class f.close() For me I think the programme is logically correct, but its giving me results which are strange. It is Printing Different Class even when sp[9] is equal to sp[10] and Same class when sp[9] is not equal to sp[10]. and sp[9] and sp[10] are simple integers like 3, 3, 4 ,4. I have a little understanding why the programme is behaving like this ? -- http://mail.python.org/mailman/listinfo/python-list
Re: using split for a string : error
On Thu, Jan 24, 2013 at 11:55 AM, Tobias M. t...@tobix.eu wrote: Hi, do a print sp after the split and you might see that the strings don't look as you expected. There might be leading or trailing whitespaces in the splitted strings and in sp[10] there probably is a line break \n at the end. To remove those unwanted characters you could use the strip() function. So your code could be: if sp[9].strip() == sp[10].strip(): print Same class else: print Different class At least this works for me when I tried it... Am 24.01.2013 11:37, schrieb inshu chauhan: Here I have a code which basically reads a csv file, tries to compare the last 2 items in each line of the file. f = open(rZ:\modules\Feature_Vectors_300_Pclass.arff) for l in f: sp = l.split(,) if len(sp) != 11: print of, l, else: #print sp[9], sp[10] if sp[9] == sp[10]: print Same class else : print Different class f.close() For me I think the programme is logically correct, but its giving me results which are strange. It is Printing Different Class even when sp[9] is equal to sp[10] and Same class when sp[9] is not equal to sp[10]. and sp[9] and sp[10] are simple integers like 3, 3, 4 ,4. I have a little understanding why the programme is behaving like this ? Yeah I tried printing, there were trailing white spaces, so i used strip() and IT Worked !!! :) Thank you -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: using split for a string : error
Thanks a lot people.. :).. :) On Thu, Jan 24, 2013 at 1:10 PM, Tobias M. t...@tobix.eu wrote: Am 24.01.2013 13:02, schrieb Chris Angelico: On Thu, Jan 24, 2013 at 10:58 PM, Tobias M. t...@tobix.eu wrote: Chris Angelico wrote: I'd not consider the performance, but the correctness. If you're expecting them to be integers, just cast them, and specifically _don't_ catch ValueError. Any non-integer value will then noisily abort the script. (It may be worth checking for blank first, though, depending on the data origin.) Well, when I said you should catch the ValueError I didn't imply you should ignore the error and supress any error messages. Of course this depents on the use case. Maybe you want to raise another exception with a more user friendly error message or you might want to skip the line and just print a warning. :) What I'm trying to say: When I give a script/program to a user who is not a python programmer I don't want him to see an error message like ValueError: invalid literal for int() with base 10: 'abc' as this would help him in no way. Sure. Definitely. But for a proglet where the programmer IS the user (which I think is one of Python's best use-cases), that exception landing on the console is better than having to think ahead of time about what might go wrong. ChrisA Okay, I absolutely agree with that :) Tobias -- http://mail.python.org/**mailman/listinfo/python-listhttp://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: Error .. Please Help
if-else doesn't define a loop, but each of the for statements do. You have defined a classification for 8 of the possible colors, leaving millions of them undefined. If the first time through the loop you manage to hit one of those undefined ones, you'll have no value for classification. So you get an exception. Yes, You are right that I will hit an exception if classification doesnot have any value. But as for the colors, actually I myself have colored the image using these 8 colors but still I think in some pixels I have put more than 1 color, thats why different colors are being encountered. Worse, if you manage to get past that first pixel with a valid classification, then for remaining pixels, you'll be using the last 'valid' classification encountered. This is the kind of quiet failure that programmers dread. Something that seems to work, but isn't even close. For this I put an else clause at end but is there a better way to avoid this kind of situation ?? If you're going to print (to file) on each iteration through the loop (except 0,0,0), you need to make sure there's always a valid value. So you need at least one more classification value, and an else clause to assign it, as ChrisA pointed out. Do you have a reason for treating (0,0,0) specially? When that value is seen, the logic skips the print as well, since continue skips to the next loop iteration. Yes , I have to skip (0,0,0), that is a kind of requirement. Are you really getting floating point values, or are they always going to be equal to an integer? Those if/elif statements might be a problem if you ever need to compare to a value like (128.4, 255.0, 255.0). I dont have values with decimal part, All values are integer. -- DaveA -- http://mail.python.org/mailman/listinfo/python-list
Error .. Please Help
In this code : import cv g = open(PointCloudmitClass.txt, w) image = cv.LoadImageM(Z:/modules/intensity_01.tif, cv.CV_LOAD_IMAGE_UNCHANGED) print image for y in xrange(0,image.height): for x in xrange(0,image.width): color = image[y,x] if color == (0.0,0.0,0.0): continue else : if color == (0.0,255.0,0.0): classification = 1 elif color == (128.0, 0.0, 255.0): classification = 2 elif color == (255.0,0.0,0.0): classification = 3 elif color == (128.0, 128.0, 128.0): classification = 4 elif color == (128.0, 64.0, 0.0): classification = 5 elif color == (0.0, 0.0, 255.0): classification = 6 elif color == (255.0, 0.0, 255.0): classification = 7 print g, x , y , color, classification I am getting the following error.. Traceback (most recent call last): File Z:\modules\Get_Classification.py, line 27, in module print g, x , y , color, classification NameError: name 'classification' is not defined Its simple error of name but m not getting why it should come as I have already defined Classification in between if-else loop ?? Thanks in Advance !!! IC -- http://mail.python.org/mailman/listinfo/python-list
Re: Index Error
Yes i tried or also but no use . Explain no use. If you mean you still fail, then what else did you try? For example, did you try interchanging the two subscripts? I've suspected all along that the meanings of row and column, x and y, [0] and [1], height and width are possibly confused. Perhaps it'd be better if you used a similar terminology everywhere. I tried using or instead of and interchanging also, still the index error is coming. x is no of column(300) and y is no of rows(3000), [0] corresponds to x i.e. column and [1] corresponds to y i.e. row and lastly height is y i.e row and width is column i.e. x Or perhaps you should simply make a class called Point, with attributes x and y. And use instances of that class rather than tuples. And start the function by defining xmax and ymax, from data.height and data.width (in whatever order matches the docs of that library you're using) Ok should be added only when this condition is satisfied print point points.append(point) change = True print change break Why do you want to terminate the loop after only iteration? snip The idea here is if no more point is added to the list of points i.e. all points surrounding the centre is zero.. I want to break the loop and go to the next point.. That's not at all what the break does. But it's probably not what you meant to say anyway. I think what you're saying is that you want to append at most one of the points from the ring. In that case, the break is appropriate, but it'd be much clearer if it were inside the clause that triggers it, the place where you say points.append(point). (naturally, it'd be at the end of that clause, following print change.) In other words indent it to line up with print change. Yes done that.. I totally agree.. Back to an earlier comment. I asked if N was ever bigger than x or bigger than y, and you said never. But your ComputeClasses will have such a case the very first time around, when cx==0, cy==0, and ring_number == 1. I doubt this , M confused.. Have you actually tested a trivial nested loop: for cy in xrange(0, data.height): for cx in xrange(0, data.width): point = data[cy, cx] to see whether it blows up. And if it does, whether reversing cy and cx will change it? Yes , I tested this. Its working fine, reversing cy and cx is not correct Your comment in the line: if dist radius :and rings should be added only when this condition is satisfied is confusing to me. How can you make the call to GenerateRing() after this test, when this test is measuring something about one of the values returned by GenerateRing ? Actually , this is one of my condition.. but i think It means that when dist is greater than radius more points will not be added to the list , So the loop should stop here, and next centre should be taken, creating second list and so on.. I must confess I have no idea what data represents. When you're doing rings, you use deltas on the cx and cy values. But when you're computing radius, you use the 3d coordinates returned by data[cx, cy]. So is data some kind of transformation, like a projection from a 3d object into a plane ? If I say data is a yml image file.. does it makes sense ? Nyways I am treating it as matrix with values. Yes you can say that it is a projection of 3D objects onto a 2D plane.. which I am finding hard to work with ! -- http://mail.python.org/mailman/listinfo/python-list
Re: Index Error
def GenerateRing(x,y, N): Generates square rings around a point in data
which has 300 columns(x) and 3000
rows(y)
indices = []
for i in xrange(-N, N):
indices.append((x+i, y-N))
indices.append((x+N, y+i))
indices.append((x-i, y+N))
indices.append((x-N, y-i))
return indices
No, this creates a one dimensional list with 2N elements of where each
element is a two item tuple.
Yes, in programme it returns a list of tuples but pysically it is creating
a ring .
I need help in this part as I am
unable to device a method in which if the points are out of index,it
should stop and
if idx[0] = 300 and idx[1] = 3000:
go to next centre and start generating
rings from there.. and again if the index is out of range .. this should
repeat
continue
else :
point = data[idx[0], idx[1]]
You can use a few different methods. This is just one example.
for idx, temp_point in enumerate(new_indices):
try:
temp_point[0]
temp_point[1]
except Exception: #Should be IndexError I think.
print 'idx: {0}\ntemp_point:{1}'.format(idx, temp_point)
# Possibly add a break or exit so you do not have to
# keep going once you hit a failure.
point = data[temp_point[0], temp_point[1]]
Thank you for the suggestion.
What is `data`? I have not seen any built-in structure that takes
a tuple in this manner...unless it is a dictionary. Or from numpy.
Given my lack of knowledge of what `data`, it could be the
problem is there. That is one reason I accessed `temp_point[0]` and
`temp_point[1]` separately.
Data is an image.
Traceback (most recent call last):
File Z:/modules/Classify.py, line 73, in module
ComputeClasses(data)
File Z:/modules/Classify.py, line 49, in ComputeClasses
point = data[idx[0], idx[1]]
error: index is out of range
Is that the actual error? If so, then the problem is not `idx` or
`temp_point` but instead `data`. If it is not the exact error, please
copy and paste the error message *exactly* as given.
Sorry but this is the actual error .
--
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Re: Index Error
I guess I have to use try and except as Chris suggested, this isn't working. -- http://mail.python.org/mailman/listinfo/python-list
Re: Error
thanx ..I understand the problem now.. On Wed, Nov 14, 2012 at 7:48 PM, MRAB pyt...@mrabarnett.plus.com wrote: On 2012-11-14 15:18, inshu chauhan wrote: for this code m getting this error : CODE : def ComputeClasses(data): radius = .5 points = [] for cy in xrange(0, data.height): for cx in xrange(0, data.width): if data[cy,cx] != (0.0,0.0,0.0): centre = data[cy, cx] points.append(centre) Look at this line: change = True It's indented the same as the preceding 'if' statement, which means that it's executed even if the body of the 'if' statement wasn't executed and it hasn't assigned to 'centre'. So 'change' has been set to True, the 'while' loop is entered, and subsequently an attempt is made to get 'centre', which hasn't been set. while change: for ring_number in xrange(1, 1000): change = False new_indices = GenerateRing(cx, cy, ring_number) for idx in new_indices: point = data[idx[0], idx[1]] if point == (0.0, 0.0, 0.0 ): continue else: dist = distance(centre, point) if dist radius : print point points.append(point) change = True print change The indentation of this line looks wrong to me: break But If I change the indentation of break towards inside, its going into infinite loop.. ??? It'll affect the 'for cx' loop at the end of its first iteration, every time. ERROR : Traceback (most recent call last): File Z:\modules\classification2.**py, line 74, in module ComputeClasses(data) File Z:\modules\classification2.**py, line 56, in ComputeClasses dist = distance(centre, point) UnboundLocalError: local variable 'centre' referenced before assignment And i am unable to understand .. WHY ? -- http://mail.python.org/**mailman/listinfo/python-listhttp://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: Error
I did the following changes in this part of my programme.. now the refereence error is removed but its showing me another error : def ComputeClasses(data): radius = .5 points = [] for cy in xrange(0, data.height): for cx in xrange(0, data.width): if data[cy,cx] == (0.0,0.0,0.0): continue else : centre = data[cy, cx] print centre points.append(centre) change = True while change: for ring_number in xrange(1, 1000): change = False new_indices = GenerateRing(cx, cy, ring_number) for idx in new_indices: point = data[idx[0], idx[1]] if point == (0.0, 0.0, 0.0 ): continue else: dist = distance(centre, point) if dist radius : print point points.append(point) change = True print change break print points ERROR : Traceback (most recent call last): File Z:/modules/classification1.py, line 71, in module ComputeClasses(data) File Z:/modules/classification1.py, line 47, in ComputeClasses point = data[idx[0], idx[1]] error: index is out of range What is meant by this statement ' Index out of range ' ? Does it mean that my range 1, 1000 is exceeded ?? -- http://mail.python.org/mailman/listinfo/python-list
Re: Error
Yes you are rightI figured that out after posting to python list.. actually my index is reaching the last point.. and my prog is not doing what I want.. I am wondering why it is reaching the last point in my list .. its never stopping in between ??? On Tue, Nov 20, 2012 at 2:01 PM, Dave Angel d...@davea.name wrote: On 11/20/2012 07:31 AM, inshu chauhan wrote: I did the following changes in this part of my programme.. now the refereence error is removed but its showing me another error : def ComputeClasses(data): radius = .5 points = [] for cy in xrange(0, data.height): for cx in xrange(0, data.width): if data[cy,cx] == (0.0,0.0,0.0): continue else : centre = data[cy, cx] print centre points.append(centre) change = True while change: for ring_number in xrange(1, 1000): change = False new_indices = GenerateRing(cx, cy, ring_number) for idx in new_indices: point = data[idx[0], idx[1]] if point == (0.0, 0.0, 0.0 ): continue else: dist = distance(centre, point) if dist radius : print point points.append(point) change = True print change break print points ERROR : Traceback (most recent call last): File Z:/modules/classification1.py, line 71, in module ComputeClasses(data) File Z:/modules/classification1.py, line 47, in ComputeClasses point = data[idx[0], idx[1]] error: index is out of range What is meant by this statement ' Index out of range ' ? Does it mean that my range 1, 1000 is exceeded ?? When you're using custom classes that mimic the standard ones, the error can mean most anything. But assuming the design was to keep as close as possible, it simply means that you're subscripting a list with an index that's too large or too small. So if idx is a list that has only one element, element number zero, then idx[1] would be out of range. On the same line, if data is acting kind of like a two-dimensional list, then it has limits on each dimension, and either idx[0] is too big/small for the first dimension, or idx[1] is too big or small for the second. First thing is to figure out which part of this expression is causing the exception. So do a separate pair of assignments, dummy0 = idx[0] dummy1 = idx[1] and then point = data[dummy0, dummy1] Incidentally, if idx is a tuple or a list, of exactly two items, then you could just say point = data[*idx] Anyway, if that still doesn't make things clear, then print dummy0 and dummy1 before the point= line. That way you can see the last value, the one it dies on, just before the stack trace. Naturally, you could also print the size attributes of the data item as well. -- DaveA -- http://mail.python.org/mailman/listinfo/python-list
Index Error
def distance(c, p): dist = sqrt( ((c[0]-p[0])**2) + ((c[1]-p[1])**2) + ((c[2]-p[2])**2) ) return dist def GenerateRing(x,y, N): Generates square rings around a point in data which has 300 columns(x) and 3000 rows(y) indices = [] for i in xrange(-N, N): indices.append((x+i, y-N)) indices.append((x+N, y+i)) indices.append((x-i, y+N)) indices.append((x-N, y-i)) return indices def ComputeClasses(data): radius = .5 points = [] for cy in xrange(0, data.height): for cx in xrange(0, data.width): if data[cy,cx] == (0.0,0.0,0.0): continue else : centre = data[cy, cx] points.append(centre) change = True while change: for ring_number in xrange(1, 100): change = False new_indices = GenerateRing(cx, cy, ring_number) print new_indices for idx in new_indices: I need help in this part as I am unable to device a method in which if the points are out of index,it should stop and if idx[0] = 300 and idx[1] = 3000: go to next centre and start generating rings from there.. and again if the index is out of range .. this should repeat continue else : point = data[idx[0], idx[1]] if point == (0.0, 0.0, 0.0 ): print point continue else: dist = distance(centre, point) print dist if dist radius : and rings should be added only when this condition is satisfied print point points.append(point) change = True print change break print points ERROR now : data loaded [(296, 403), (298, 403), (298, 405), (296, 405), (297, 403), (298, 404), (297, 405), (296, 404)] ... I am printing Indices to know what index it dies out.. Traceback (most recent call last): File Z:/modules/Classify.py, line 73, in module ComputeClasses(data) File Z:/modules/Classify.py, line 49, in ComputeClasses point = data[idx[0], idx[1]] error: index is out of range -- http://mail.python.org/mailman/listinfo/python-list
Re: Index Error
I am using python 2.7.3 , so can it be done in that ? On Tue, Nov 20, 2012 at 2:48 PM, Chris Angelico ros...@gmail.com wrote: On Wed, Nov 21, 2012 at 12:43 AM, inshu chauhan insidesh...@gmail.com wrote: I need help in this part as I am unable to device a method in which if the points are out of index,it should stop. Traceback (most recent call last): File Z:/modules/Classify.py, line 73, in module ComputeClasses(data) File Z:/modules/Classify.py, line 49, in ComputeClasses point = data[idx[0], idx[1]] error: index is out of range When Python throws an exception, you can catch it and handle it as you please. In this instance, it seems to me you want to break out of one loop (if I've read your comments correctly), so just bracket that loop with try... except. Start here: http://docs.python.org/3.3/tutorial/errors.html ChrisA -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: Index Error
On Tue, Nov 20, 2012 at 3:00 PM, Chris Angelico ros...@gmail.com wrote: On Wed, Nov 21, 2012 at 12:57 AM, inshu chauhan insidesh...@gmail.com wrote: I am using python 2.7.3 , so can it be done in that ? (Please don't top-post; just delete the couple of blank lines that gmail oh so kindly provides, and type your response at the bottom. You may also want to consider trimming the quoted text to just what you actually need.) Yes, it certainly can. Go to the docs page I linked to, then up the top left you'll see this: Python » 3.3.0 Documentation with the 3.3.0 part a drop-down list. Drop it down and select 2.7, and you'll see the equivalent page for version 2.7.3. Have fun! ChrisA -- http://mail.python.org/mailman/listinfo/python-list Ok.. Thanks a ton ... -- http://mail.python.org/mailman/listinfo/python-list
Re: Index Error
def GenerateRing(x,y, N): Generates square rings around a point in data which has 300 columns(x) and 3000 rows(y) indices = [] for i in xrange(-N, N): indices.append((x+i, y-N)) indices.append((x+N, y+i)) indices.append((x-i, y+N)) indices.append((x-N, y-i)) return indices Is it possible that N is greater than either x or y ? Are negative subscripts permissible? You should consider doing the clipping logic in this function, perhaps by passing xlimit and ylimit in as arguments. Yes N cannot be greater than x and y and it cant be negative too... I need help in this part as I am unable to device a method in which if the points are out of index,it should stop and if idx[0] = 300 and idx[1] = 3000: go to next centre and start generating rings from there.. and again if the index is out of range .. this should repeat This is where you're trying to clip the values that may be outside of the total matrix. Yes I am trying to clip the values here but its not working actually , I mean not at all working You do not want and in that expression. The way you've coded it, it'll only skip items in which both indices are out of range. Change it to if idx[0] = data.width or idx[1] = data.height: and depending on your answer to my earlier query, you may want to also check if either subscript is negative. continue else : point = data[idx[0], idx[1]] if point == (0.0, 0.0, 0.0 ): print point continue else: dist = distance(centre, point) print dist if dist radius : and rings should be added only when this condition is satisfied print point points.append(point) change = True print change break Why do you want to terminate the loop after only iteration? I dint get your question ?? -- http://mail.python.org/mailman/listinfo/python-list
Re: Index Error
So did you read the following paragraphs? You should not be using and in that expression. Yes i tried or also but no use . You do not want and in that expression. The way you've coded it, it'll only skip items in which both indices are out of range. Change it to if idx[0] = data.width or idx[1] = data.height: and depending on your answer to my earlier query, you may want to also check if either subscript is negative. continue else : point = data[idx[0], idx[1]] if point == (0.0, 0.0, 0.0 ): print point continue else: dist = distance(centre, point) print dist if dist radius : and rings should be added only when this condition is satisfied print point points.append(point) change = True print change break Why do you want to terminate the loop after only iteration? I dint get your question ?? You have a break there. What's it for? It'll make sure you only process one of the idx values from new_indices. i doubt that's what you intended. The idea here is if no more point is added to the list of points i.e. all points surrounding the centre is zero.. I want to break the loop and go to the next point.. -- http://mail.python.org/mailman/listinfo/python-list
Re: Index Error
The catch to the approach suggested by Chris is that you DON'T want to break out of the whole loop when one value is out of range. You only want to skip that one point. Yes I want to skip only that one point (centre) but try and expect seems to be the last option.. I would like to try other ways first.. -- http://mail.python.org/mailman/listinfo/python-list
Re: Index Error
I dont want error actually to come. With try nd except , the error will come but without affecting my prog... -- http://mail.python.org/mailman/listinfo/python-list
Error
for this code m getting this error : CODE : def ComputeClasses(data): radius = .5 points = [] for cy in xrange(0, data.height): for cx in xrange(0, data.width): if data[cy,cx] != (0.0,0.0,0.0): centre = data[cy, cx] points.append(centre) change = True while change: for ring_number in xrange(1, 1000): change = False new_indices = GenerateRing(cx, cy, ring_number) for idx in new_indices: point = data[idx[0], idx[1]] if point == (0.0, 0.0, 0.0 ): continue else: dist = distance(centre, point) if dist radius : print point points.append(point) change = True print change break ERROR : Traceback (most recent call last): File Z:\modules\classification2.py, line 74, in module ComputeClasses(data) File Z:\modules\classification2.py, line 56, in ComputeClasses dist = distance(centre, point) UnboundLocalError: local variable 'centre' referenced before assignment And i am unable to understand .. WHY ? -- http://mail.python.org/mailman/listinfo/python-list
Fwd: error
No answers for my question ?? :O -- http://mail.python.org/mailman/listinfo/python-list
Re: error
http://www.ymlgroup.com/obscurehiddenlocation/downloads site, and imported it using from notzanzibar import DataType. No i haven't downloaded it.. and this site is not opening... Then you'd have instantiated it in some code like data = DataType(filename) and then the type of data would be notzanzibar.DataType and the docs would be probably available somewhere on www.invalid.com/docs This site is also blocked here. The only new guess: A 3D image would presumably have 3 subscripts, and you're only supplying two. Yes a 3D image has 3 subscripts but m trying to access all three through using only 2 subsscripts i.e X and Y If you want help, be explicit: 1) what version of CPython are you using, and on what OS? I am using 2.7.3 on windows 7 2) what web site did you download some extra library from ? The only extra libary i am using is Opencv , downloaded from http://sourceforge.net/projects/opencvlibrary/ 3) what import statement did you use ? import cv 4) How are all those global variables initialized ? see attached file 5) What command did you use to start the script ? Did you run it from command.com, or from some IDE ? Yes I am running it through IDLE GUI 5) Exactly what error message did you get, including the traceback ? Traceback (most recent call last): File Z:\modules\Masking_an_image_dynamically.py, line 155, in module AccessPixels(data) File Z:\modules\.py, line 147, in AccessPixels CreateMask(data, x, y) File Z:\modules\new_classification.py, line 110, in CreateMask point = data[iy, ix ] error: index is out of range The line numbers here and the file attached may be different because I have removed a lot of print statements which I was using to debug the error.. 6) What have you done to try to figure out your own error? I have trying print out variables and Indices at each step.. Zero Piraeus : Where are you ? Masking_an_image_dynamically.py Description: Binary data -- http://mail.python.org/mailman/listinfo/python-list
Re: error
I attached a wrong file...Right file is attached here On Fri, Nov 9, 2012 at 11:53 AM, inshu chauhan insidesh...@gmail.comwrote: http://www.ymlgroup.com/obscurehiddenlocation/downloads site, and imported it using from notzanzibar import DataType. No i haven't downloaded it.. and this site is not opening... Then you'd have instantiated it in some code like data = DataType(filename) and then the type of data would be notzanzibar.DataType and the docs would be probably available somewhere on www.invalid.com/docs This site is also blocked here. The only new guess: A 3D image would presumably have 3 subscripts, and you're only supplying two. Yes a 3D image has 3 subscripts but m trying to access all three through using only 2 subsscripts i.e X and Y If you want help, be explicit: 1) what version of CPython are you using, and on what OS? I am using 2.7.3 on windows 7 2) what web site did you download some extra library from ? The only extra libary i am using is Opencv , downloaded from http://sourceforge.net/projects/opencvlibrary/ 3) what import statement did you use ? import cv 4) How are all those global variables initialized ? see attached file 5) What command did you use to start the script ? Did you run it from command.com, or from some IDE ? Yes I am running it through IDLE GUI 5) Exactly what error message did you get, including the traceback ? Traceback (most recent call last): File Z:\modules\Masking_an_image_dynamically.py, line 155, in module AccessPixels(data) File Z:\modules\.py, line 147, in AccessPixels CreateMask(data, x, y) File Z:\modules\new_classification.py, line 110, in CreateMask point = data[iy, ix ] error: index is out of range The line numbers here and the file attached may be different because I have removed a lot of print statements which I was using to debug the error.. 6) What have you done to try to figure out your own error? I have trying print out variables and Indices at each step.. Zero Piraeus : Where are you ? Masking_an_image_dynamically.py Description: Binary data -- http://mail.python.org/mailman/listinfo/python-list
Re: error
Please Ignore the above two files attached,,, See this one On Fri, Nov 9, 2012 at 12:47 PM, inshu chauhan insidesh...@gmail.comwrote: I attached a wrong file...Right file is attached here On Fri, Nov 9, 2012 at 11:53 AM, inshu chauhan insidesh...@gmail.comwrote: http://www.ymlgroup.com/obscurehiddenlocation/downloads site, and imported it using from notzanzibar import DataType. No i haven't downloaded it.. and this site is not opening... Then you'd have instantiated it in some code like data = DataType(filename) and then the type of data would be notzanzibar.DataType and the docs would be probably available somewhere on www.invalid.com/docs This site is also blocked here. The only new guess: A 3D image would presumably have 3 subscripts, and you're only supplying two. Yes a 3D image has 3 subscripts but m trying to access all three through using only 2 subsscripts i.e X and Y If you want help, be explicit: 1) what version of CPython are you using, and on what OS? I am using 2.7.3 on windows 7 2) what web site did you download some extra library from ? The only extra libary i am using is Opencv , downloaded from http://sourceforge.net/projects/opencvlibrary/ 3) what import statement did you use ? import cv 4) How are all those global variables initialized ? see attached file 5) What command did you use to start the script ? Did you run it from command.com, or from some IDE ? Yes I am running it through IDLE GUI 5) Exactly what error message did you get, including the traceback ? Traceback (most recent call last): File Z:\modules\Masking_an_image_dynamically.py, line 155, in module AccessPixels(data) File Z:\modules\.py, line 147, in AccessPixels CreateMask(data, x, y) File Z:\modules\new_classification.py, line 110, in CreateMask point = data[iy, ix ] error: index is out of range The line numbers here and the file attached may be different because I have removed a lot of print statements which I was using to debug the error.. 6) What have you done to try to figure out your own error? I have trying print out variables and Indices at each step.. Zero Piraeus : Where are you ? Masking_an_image_dynamically.py Description: Binary data -- http://mail.python.org/mailman/listinfo/python-list
Re: error
Actually this one.. and its the last.. On Fri, Nov 9, 2012 at 2:59 PM, inshu chauhan insidesh...@gmail.com wrote: Please Ignore the above two files attached,,, See this one On Fri, Nov 9, 2012 at 12:47 PM, inshu chauhan insidesh...@gmail.comwrote: I attached a wrong file...Right file is attached here On Fri, Nov 9, 2012 at 11:53 AM, inshu chauhan insidesh...@gmail.comwrote: http://www.ymlgroup.com/obscurehiddenlocation/downloads site, and imported it using from notzanzibar import DataType. No i haven't downloaded it.. and this site is not opening... Then you'd have instantiated it in some code like data = DataType(filename) and then the type of data would be notzanzibar.DataType and the docs would be probably available somewhere on www.invalid.com/docs This site is also blocked here. The only new guess: A 3D image would presumably have 3 subscripts, and you're only supplying two. Yes a 3D image has 3 subscripts but m trying to access all three through using only 2 subsscripts i.e X and Y If you want help, be explicit: 1) what version of CPython are you using, and on what OS? I am using 2.7.3 on windows 7 2) what web site did you download some extra library from ? The only extra libary i am using is Opencv , downloaded from http://sourceforge.net/projects/opencvlibrary/ 3) what import statement did you use ? import cv 4) How are all those global variables initialized ? see attached file 5) What command did you use to start the script ? Did you run it from command.com, or from some IDE ? Yes I am running it through IDLE GUI 5) Exactly what error message did you get, including the traceback ? Traceback (most recent call last): File Z:\modules\Masking_an_image_dynamically.py, line 155, in module AccessPixels(data) File Z:\modules\.py, line 147, in AccessPixels CreateMask(data, x, y) File Z:\modules\new_classification.py, line 110, in CreateMask point = data[iy, ix ] error: index is out of range The line numbers here and the file attached may be different because I have removed a lot of print statements which I was using to debug the error.. 6) What have you done to try to figure out your own error? I have trying print out variables and Indices at each step.. Zero Piraeus : Where are you ? Masking_an_image_dynamically.py Description: Binary data -- http://mail.python.org/mailman/listinfo/python-list
Re: error
Actually data is neither a zanzibar nor a class nor a list.. its a yml image. with pixels I am trying to access pixels of a 3D image through this programme.. On Tue, Nov 6, 2012 at 8:59 PM, woooee woo...@gmail.com wrote: From this line, data appears to be a class if 0 ix data.width and 0 iy data.height: From this line, data appears to be a list, although a two dimensional list would be accessed as data[ix][iy] point = data[ix, iy] Also, returning a list from a function is a matter of preference. Some people argue that it should be returned to make it obvious. If you do not know the difference between what is mutable and what is not mutable, then return everything until you do. -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
error
I am getting this error while running my programme.. : error: index is out of range I cannot find a valid reason for it in my prog can somebody suggest what may be possible reasons for this error.. The part of the code is : def addpoints (data, points, ix, iy): # makes a list of relevant points if 0 ix data.width and 0 iy data.height: point = data[ix, iy] if point != (0.0, 0.0, 0.0): points.append(point) return points for dx in xrange(-mask_size2, mask_size2 + 1): for dy in xrange(-mask_size2, mask_size2 + 1): ix, iy = x + dx, y + dy addpoints(data, points, ix , iy ) -- http://mail.python.org/mailman/listinfo/python-list
Difference between range and xrange ??
what is the difference between range and xrange.. both seem to work the same. ? And which should be used where and in what situations.. ?? -- http://mail.python.org/mailman/listinfo/python-list
python and Open cv
How to load a yml file in python and work with it ?? I used : import cv data = cv.Load(Z:/data/xyz_0_ 300.yml) But when I print data.. it just gives the detail of the image like number of rows and columns etc I want read what is there in the pixel of the image.. I tried to use the following code .. but it gives me only the pixel values not the information contained in pixel ?? def AccessPixels(img): for y in range(0, img.height): for x in range(0, img.width): cv.Get2D(img, y, x) # Slow get pixel value. cv.Set2D(img, y, x, (0, 0, 0, 0)) # Slow set pixel value. can somebody help.. thanx in advance !!! -- http://mail.python.org/mailman/listinfo/python-list
Fwd: python and Open cv
-- Forwarded message -- From: inshu chauhan insidesh...@gmail.com Date: Thu, Nov 1, 2012 at 1:26 PM Subject: Re: python and Open cv To: Mark Lawrence breamore...@yahoo.co.uk I am sorry.. but I need to know what are the rules and what about gmail ?? Many people are using gmail to mail to the list. On Thu, Nov 1, 2012 at 12:15 PM, Mark Lawrence breamore...@yahoo.co.ukwrote: On 01/11/2012 08:55, inshu chauhan wrote: How to load a yml file in python and work with it ?? I used : import cv data = cv.Load(Z:/data/xyz_0_ 300.yml) But when I print data.. it just gives the detail of the image like number of rows and columns etc I want read what is there in the pixel of the image.. I tried to use the following code .. but it gives me only the pixel values not the information contained in pixel ?? def AccessPixels(img): for y in range(0, img.height): for x in range(0, img.width): cv.Get2D(img, y, x) # Slow get pixel value. cv.Set2D(img, y, x, (0, 0, 0, 0)) # Slow set pixel value. can somebody help.. thanx in advance !!! I think the subject should be changed to Obnoxious postings from Google Groups, given this is the same question from the same person within 24 hours but a different subject line, and from a gmail address. -- Cheers. Mark Lawrence. -- http://mail.python.org/**mailman/listinfo/python-listhttp://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
pythonic way
what is the most pythonic way to do this : if 0 ix 10 and 0 iy 10 ??? -- http://mail.python.org/mailman/listinfo/python-list
Re: python and Open cv
On Thu, Nov 1, 2012 at 7:02 PM, Paul Rudin paul.nos...@rudin.co.uk wrote: Zero Piraeus sche...@gmail.com writes: There aren't any rules about gmail (except the unwritten rule that to be a real geek you need to use a mail client that takes a whole weekend to configure, and another three years to properly understand). :D :D :D Ha! 3 years? I've been using gnus for nearly 20 years and I still don't understand it! -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: pythonic way
OK ..I got it.. On Thu, Nov 1, 2012 at 5:54 PM, Zero Piraeus sche...@gmail.com wrote: : On 1 November 2012 11:32, inshu chauhan insidesh...@gmail.com wrote: what is the most pythonic way to do this : if 0 ix 10 and 0 iy 10 ??? As everyone else has said, it's perfectly pythonic once you stick the colon on the end. You might find it more instantly readable with some extra parentheses: if (0 ix 10) and (0 iy 10): # do something ... but that's really just down to taste. -[]z. -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
working with yml files in python and opencv
How to load a yml file in python and work with it ?? I used : import cv data = cv.Load(Z:/data/xyz_0_300.yml) But when I print data.. it just gives the detail of the image like number of rows and columns etc I want read what is there in the pixel of the image.. can somebody help.. thanx in advance !!! -- http://mail.python.org/mailman/listinfo/python-list
Re: can we append a list with another list in Python ?
Actually what I wanted to do is : suppose there are 3 lists : like for xample : clist = [] an empty list , alist = [1,2,3], blist = [4,5,6] and the I want the result is clist = [ [1,2,3], [4,5,6] ..] then I want to read all the lists in clist one by one like : for item in clist: print item which should print: [1,2,3] [4,5,6] On Tue, Oct 23, 2012 at 10:10 PM, inshu chauhan insidesh...@gmail.comwrote: ok I got it guys... On Tue, Oct 23, 2012 at 10:08 PM, Joshua Landau joshua.landau...@gmail.com wrote: On 23 October 2012 21:06, Joshua Landau joshua.landau...@gmail.comwrote: On 23 October 2012 21:03, Joshua Landau joshua.landau...@gmail.comwrote: On 23 October 2012 12:07, Jean-Michel Pichavant jeanmic...@sequans.com wrote: - Original Message - Thankyou.. but my problem is different than simply joining 2 lists and it is done now :) A lot of people though you were asking for joining lists, you description was misleading. I'll take a guess: you want to flatten a list of list. Nested list comprehensions can do the trick. aList =[[1,5], [2,'a']] [item for sublist in aList for item in sublist] ... [1, 5, 2, 'a'] I find it rather difficult to read though. We have a library function for this, in the one-and-only itertools. listoflists = [list(range(x, 2*x)) for x in range(5)] listoflists [[], [1], [2, 3], [3, 4, 5], [4, 5, 6, 7]] from itertools import chain list(chain.from_iterable(listoflists)) [1, 2, 3, 3, 4, 5, 4, 5, 6, 7] It does exactly what it says... fast and easy-to-read. Note that I think what he really wanted is to go from a, b, c = [list(x) for x in (range(10), range(11, 20), range(21, 30))] to list(range(30)) UNDO! UNDO! UNDO! I *meant *to say: Note that I think what he really wanted is to go from a, b, c = [list(x) for x in (range(10), range(11, 20), range(21, 30))] to [a, b, c] -- http://mail.python.org/mailman/listinfo/python-list
Re: can we append a list with another list in Python ?
clist = alist, blist This may work i guess becuase i want list within list [ [1,2,3] , [4,5,6]] or if the clist initial contents were relevant, perhaps you mean clist += alist, blist But not this because it will simply concatenate the list like [1,2,3,4,5,6] .. I dont want this actaully... -- DaveA -- http://mail.python.org/mailman/listinfo/python-list
Re: can we append a list with another list in Python ?
or if the clist initial contents were relevant, perhaps you mean clist += alist, blist But not this because it will simply concatenate the list like [1,2,3,4,5,6] .. I dont want this actaully... No, it won't. Try it to see Ok but it should be clist + = [alist, blist ] -- DaveA -- http://mail.python.org/mailman/listinfo/python-list
Re: can we append a list with another list in Python ?
Is this what you mean: list_1 = [i for i in range(0,5)] list_2 = [i for i in range(5,11)] for i in list_2: ... list_1.append(i) ... list_1 [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] or would another example help you out more? No but really sorry this is what I DONT WANT... The output I want to have is : [ [0, 1, 2, 3, 4 ], [5, 6, 7, 8, 9, 10] ]. -- Best Regards, David Hutto CEO: http://www.hitwebdevelopment.com -- http://mail.python.org/mailman/listinfo/python-list
Re: can we append a list with another list in Python ?
Yes Dave ..You are right and my problem is solved now.. Thanx to all... On Thu, Oct 25, 2012 at 11:55 AM, David Hutto dwightdhu...@gmail.comwrote: On Thu, Oct 25, 2012 at 5:51 AM, inshu chauhan insidesh...@gmail.com wrote: Is this what you mean: list_0 = [] list_1 = [i for i in range(0,5)] list_2 = [i for i in range(5,11)] list_0.append(list_1) list_0.append(list_2) for i in list_2: ... list_1.append(i) ... list_1 [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] or would another example help you out more? No but really sorry this is what I DONT WANT... The output I want to have is : [ [0, 1, 2, 3, 4 ], [5, 6, 7, 8, 9, 10] ]. Then, this is what you want : david@david-desktop:~$ python Python 2.7.3 (default, Aug 1 2012, 05:16:07) [GCC 4.6.3] on linux2 Type help, copyright, credits or license for more information. list_0 = [] list_1 = [i for i in range(0,5)] list_2 = [i for i in range(5,11)] list_0.append(list_1) list_0.append(list_2) list_0 [[0, 1, 2, 3, 4], [5, 6, 7, 8, 9, 10]] -- Best Regards, David Hutto CEO: http://www.hitwebdevelopment.com -- http://mail.python.org/mailman/listinfo/python-list
Re: can we append a list with another list in Python ?
On Thu, Oct 25, 2012 at 12:04 PM, David Hutto dwightdhu...@gmail.comwrote: On Thu, Oct 25, 2012 at 5:58 AM, inshu chauhan insidesh...@gmail.com wrote: Yes Dave ..You are right and my problem is solved now.. Thanx to all... On Thu, Oct 25, 2012 at 11:55 AM, David Hutto dwightdhu...@gmail.com wrote: On Thu, Oct 25, 2012 at 5:51 AM, inshu chauhan insidesh...@gmail.com wrote: Is this what you mean: list_0 = [] list_1 = [i for i in range(0,5)] list_2 = [i for i in range(5,11)] list_0.append(list_1) list_0.append(list_2) for i in list_2: ... list_1.append(i) ... list_1 [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] or would another example help you out more? No but really sorry this is what I DONT WANT... The output I want to have is : [ [0, 1, 2, 3, 4 ], [5, 6, 7, 8, 9, 10] ]. Then, this is what you want : david@david-desktop:~$ python Python 2.7.3 (default, Aug 1 2012, 05:16:07) [GCC 4.6.3] on linux2 Type help, copyright, credits or license for more information. list_0 = [] list_1 = [i for i in range(0,5)] list_2 = [i for i in range(5,11)] list_0.append(list_1) list_0.append(list_2) list_0 [[0, 1, 2, 3, 4], [5, 6, 7, 8, 9, 10]] if you have a format for the lists, there might be an easier way, or simpler. How are the lists coming in? The list are in form of first list like [(x,y,z) ] and another as [(a,b,c), (a+i, b+i, c+i).] -- Best Regards, David Hutto CEO: http://www.hitwebdevelopment.com -- http://mail.python.org/mailman/listinfo/python-list
Re: can we append a list with another list in Python ?
On Thu, Oct 25, 2012 at 12:17 PM, David Hutto dwightdhu...@gmail.comwrote: On Thu, Oct 25, 2012 at 6:12 AM, inshu chauhan insidesh...@gmail.com wrote: On Thu, Oct 25, 2012 at 12:04 PM, David Hutto dwightdhu...@gmail.com wrote: On Thu, Oct 25, 2012 at 5:58 AM, inshu chauhan insidesh...@gmail.com wrote: Yes Dave ..You are right and my problem is solved now.. Thanx to all... On Thu, Oct 25, 2012 at 11:55 AM, David Hutto dwightdhu...@gmail.com wrote: On Thu, Oct 25, 2012 at 5:51 AM, inshu chauhan insidesh...@gmail.com wrote: Is this what you mean: list_0 = [] list_1 = [i for i in range(0,5)] list_2 = [i for i in range(5,11)] list_0.append(list_1) list_0.append(list_2) for i in list_2: ... list_1.append(i) ... list_1 [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10] or would another example help you out more? No but really sorry this is what I DONT WANT... The output I want to have is : [ [0, 1, 2, 3, 4 ], [5, 6, 7, 8, 9, 10] ]. Then, this is what you want : david@david-desktop:~$ python Python 2.7.3 (default, Aug 1 2012, 05:16:07) [GCC 4.6.3] on linux2 Type help, copyright, credits or license for more information. list_0 = [] list_1 = [i for i in range(0,5)] list_2 = [i for i in range(5,11)] list_0.append(list_1) list_0 = [list_1,list_2] list_0.append(list_2) list_0 [[0, 1, 2, 3, 4], [5, 6, 7, 8, 9, 10]] if you have a format for the lists, there might be an easier way, or simpler. How are the lists coming in? The list are in form of first list like [(x,y,z) ] and another as [(a,b,c), (a+i, b+i, c+i).] This shows tuples though, not appended lists, which are immutable. My mistake it is : The list are in form of first list like [ [x,y,z] ] and another as [ [a,b,c], [a+i, b+i, c+i] and so on .] -- Best Regards, David Hutto CEO: http://www.hitwebdevelopment.com -- http://mail.python.org/mailman/listinfo/python-list
classes
I was just trying out a programme for learning classes in python The prog below is showing an error which it should not show : class Bag: def __init__(self, x): self.data = [] def add(self, x): self.data.append(x) def addtwice(self, x): self.add(x) self.add(x) y = Bag(4) print Adding twice of %4.2f gives % (y.addtwice()) Error is : Traceback (most recent call last): File Z:\learning Python\learn5.py, line 35, in module print Adding twice of %4.2f gives % (y.addtwice()) TypeError: addtwice() takes exactly 2 arguments (1 given) why the prog is having this error with self nd x as arguments ??? -- http://mail.python.org/mailman/listinfo/python-list
Re: classes
I was just trying out a programme for learning classes in python The prog below is showing an error which it should not show : class Bag: def __init__(self, x): self.data = [] You do nothing with x here. Right so x shouldnot be in the argument. Fine *class Bag: def __init__(self): self.data = []* def add(self, x): self.data.append(x) def addtwice(self, x): self.add(x) self.add(x) y = Bag(4) Create y with an argument of 4 'which is discarded in the initialiser.' means ?? print Adding twice of %4.2f gives % (y.addtwice()) There's no argument passed to addtwice here. ' why am I not passing y to addtwice here ?? Error is : Traceback (most recent call last): File Z:\learning Python\learn5.py, line 35, in module print Adding twice of %4.2f gives % (y.addtwice()) TypeError: addtwice() takes exactly 2 arguments (1 given) Exactly what I'd expect to happen. What did you expect? I am learning why the prog is having this error with self nd x as arguments ??? What x argument? Clearly wrong as I've pointed out above. How can i correct it ?? -- Cheers. Mark Lawrence. -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: classes
I changed the programme to this : class Bag: def __init__(self): self.data = [] def add(self, x): self.data.append(x) def addtwice(self, x): self.add(x) self.add(x) return x y = Bag() print y.addtwice(4) Now its not showing any error but result is same as the number passed for adding twice On Wed, Oct 24, 2012 at 2:55 PM, Dave Angel d...@davea.name wrote: On 10/24/2012 08:11 AM, inshu chauhan wrote: I was just trying out a programme for learning classes in python The prog below is showing an error which it should not show : class Bag: def __init__(self, x): self.data = [] def add(self, x): self.data.append(x) def addtwice(self, x): self.add(x) self.add(x) y = Bag(4) print Adding twice of %4.2f gives % (y.addtwice()) Perhaps you're confusing the two x parameters. They are totally independent local variables, and the value of one is not in any way remembered for the other. When you want to save things between multiple methods of an object, then store them in the object, perhaps in self.data As it stands, the __init__ does not save the x at all, so the 4 that's passed into the initializer is thrown away. You call addtwice(), but don't supply any value to add. y serves as the self value, but you have no x value. What value did you intend to add? You'll have another problem, in that addtwice() doesn't return any value (so it returns None). Therefore the print isn't going to work. Please separate the print from the calculations, and the problems will be lots easier to figure out. The wording of the string implies it's going to display two values, but the only value given it is None. Error is : Traceback (most recent call last): File Z:\learning Python\learn5.py, line 35, in module print Adding twice of %4.2f gives % (y.addtwice()) TypeError: addtwice() takes exactly 2 arguments (1 given) why the prog is having this error with self nd x as arguments ??? self and x are parameters. You don't pass an argument for x to be bound to. -- DaveA -- http://mail.python.org/mailman/listinfo/python-list
Re: classes
ok.. This was an example i was trying to run from http://docs.python.org/tutorial/classes.html ... On Wed, Oct 24, 2012 at 3:48 PM, Chris Angelico ros...@gmail.com wrote: On Thu, Oct 25, 2012 at 12:02 AM, inshu chauhan insidesh...@gmail.com wrote: I changed the programme to this : def addtwice(self, x): self.add(x) self.add(x) return x y = Bag() print y.addtwice(4) Now its not showing any error but result is same as the number passed for adding twice Do you understand how function calls work? A function like y.addtwice is called with an argument of 4, and the return value from the function is the value of the expression. some_value = y.addtwice(4) print some_value Take the return value and put it in the place where the function call was. In this case, the return value is x, the number you passed in as an argument. What exactly do you expect addtwice to return? Should it return the bag object (self)? Should it return True to say that it's been added successfully (or False if there's an error)? Should it return the number of items in the bag? Should it return 0 for success and a nonzero error code for failure? Should it always return None, throwing an exception if anything goes wrong? All of these make sense, you just have to choose which one you want. (I'm handwaving away a lot of complexity here, like un/bound methods and member lookups. Bear with me. I'm also ignoring the fact that some things just aren't Pythonic. The bear isn't complaining about that, so nor should you.) ChrisA -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Appending a list using list obtained from a class
I am having a problem, I have a class which return me a list. I want to append another list using this list outside the Class. can i do it ? if yes how ? And can i use Userlist function for this ?? -- http://mail.python.org/mailman/listinfo/python-list
Re: Appending a list using list obtained from a class
yes this i know very well.. but the problem is not so simple... the class is returning the list , and i want to append the list outside the class... main problem is this I know how to append a list with a list nd stuff.. On Wed, Oct 24, 2012 at 4:41 PM, Demian Brecht demianbre...@gmail.comwrote: On 2012-10-24, at 7:37 AM, inshu chauhan insidesh...@gmail.com wrote: I am having a problem, I have a class which return me a list. I want to append another list using this list outside the Class. can i do it ? if yes how ? And can i use Userlist function for this ?? -- http://mail.python.org/mailman/listinfo/python-list If I understand your question correctly, have you read http://docs.python.org/tutorial/datastructures.html? list_a + list_b = list_c list_a.extend(list_b) are two methods to concatenate two lists. UserList is only there for backwards compatibility (see the docs: http://docs.python.org/release/2.3/lib/module-UserList.html) Demian Brecht @demianbrecht http://demianbrecht.github.com -- http://mail.python.org/mailman/listinfo/python-list
Re: Appending a list using list obtained from a class
the class is returning the list , and i want to append the list outside the class... main problem is this What do you mean the class is returning the list? Do you mean that a class stores a list internally and you want to be able to mutate that list? Do you mean that you have a class method that returns a list? How does your particular use case differ from simply appending one list to another? Yes, a Class method returns a list. I am trying to append this in main() to make another list. But the list i am getting after appending i showing addresses like this '__main__.Point object at 0x0254FAB0' but if i print the same in the same loop its showing me numbers which i want. Why I dont know ?? I know how to append a list with a list nd stuff.. Without further clarification, this seems to be exactly what you're asking how to do.. yeah may i make misunderstanding Demian Brecht @demianbrecht http://demianbrecht.github.com -- http://mail.python.org/mailman/listinfo/python-list
Fwd: can we append a list with another list in Python ?
-- Forwarded message -- From: Zero Piraeus sche...@gmail.com Date: Tue, Oct 23, 2012 at 11:14 AM Subject: Re: can we append a list with another list in Python ? To: inshu chauhan insidesh...@gmail.com : On 23 October 2012 05:01, inshu chauhan insidesh...@gmail.com wrote: this is because this makes a single list out of 2 lists.. but I want to retain both lists as lists within list... I hope u got it ?? my problem is for example : x = [1,2,3] y = [10, 20, 30] I want the output to be : [[1,2,3], [10, 20, 30]] .. a list within list then i want to process each list in the big list using another function For the example above, you'd just do: x = [1, 2, 3] y = [10, 20, 30] z = [x, y] z [[1, 2, 3], [10, 20, 30]] ... but presumably there'll be more than two, and you're creating them in some kind of loop? In that case, append is fine. For example: result = [] for word in squee, kapow, vroom: ... seq = list(word) # or whatever you're doing to create the list ... result.append(seq) ... result [['s', 'q', 'u', 'e', 'e'], ['k', 'a', 'p', 'o', 'w'], ['v', 'r', 'o', 'o', 'm']] By the way - you only replied to me. Do you mind if I forward this back to the list? -[]z. -- http://mail.python.org/mailman/listinfo/python-list
Re: can we append a list with another list in Python ?
Thankyou.. but my problem is different than simply joining 2 lists and it is done now :) On Tue, Oct 23, 2012 at 11:38 AM, Joshua Landau joshua.landau...@gmail.comwrote: On 23/10/2012, inshu chauhan insidesh...@gmail.com wrote: can we append a list with another list in Python ? using the normal routine syntax but with a for loop ?? I assume you want to join two lists. You are corrrect that we can do: start = [1, 2, 3, 4] end = [5, 6, 7, 8] for end_item in end: start.append(end_item) print(start) [1, 2, 3, 4, 5, 6, 7, 8] However, it is markedly repetitive, no? This is a common enough operation that there is a shortcut to find out about it. If you want to find out what methods there are, try help(...). I can't stress this enough. help(start) Help on list object: class list(object) | list() - new empty list | list(iterable) - new list initialized from iterable's items | | Methods defined here: | | __add__(...) | x.__add__(y) == x+y ... | append(...) | L.append(object) -- append object to end ... | extend(...) | L.extend(iterable) -- extend list by appending elements from the iterable ... So list.extend seems to do exactly this! You can always check the documentation http://docs.python.org/tutorial/datastructures.html. An lo! The documentation says start.extend(end) is _equivilant_ to start[len(start):] = end. Why? Well, this uses the slicing syntax. start[:3] [1, 2, 3] start[3:] [4] start[2:3] [3] Wonderously, all these really say are ranges in the list. Hence, you can put lists in their place. start[len(start):] = end means start[-1:] = end, so what you're doing is saying the empty end part of the list is actually this new list. Hopefully that makes sense. Finally, there is another method. Instead of *changing* the list, you can make a new list which is equal to the others added together. new = start + end ___ Theses methods all have their own upsides. If you want to change the list, use .extend(). If you want to change the list, but by putting the new list somewhere inside the old one, use slicing: start = [1, 2, 3, 4] end = [5, 6, 7, 8] start[2:2] = end print(start) [1, 2, 5, 6, 7, 8, 3, 4] Looping is good for when you want to generate the extra items as you go along. Finally, if you want to keep the old list or use these inline, use +. ___ Note that, being in the unfortunate position of away from an interpreter, none of my examples are copy-pastes. Hence they may be wrong :/ # Not checked for errors, typos and my friends messing with it. -- http://mail.python.org/mailman/listinfo/python-list
Re: can we append a list with another list in Python ?
ok I got it guys... On Tue, Oct 23, 2012 at 10:08 PM, Joshua Landau joshua.landau...@gmail.comwrote: On 23 October 2012 21:06, Joshua Landau joshua.landau...@gmail.comwrote: On 23 October 2012 21:03, Joshua Landau joshua.landau...@gmail.comwrote: On 23 October 2012 12:07, Jean-Michel Pichavant jeanmic...@sequans.comwrote: - Original Message - Thankyou.. but my problem is different than simply joining 2 lists and it is done now :) A lot of people though you were asking for joining lists, you description was misleading. I'll take a guess: you want to flatten a list of list. Nested list comprehensions can do the trick. aList =[[1,5], [2,'a']] [item for sublist in aList for item in sublist] ... [1, 5, 2, 'a'] I find it rather difficult to read though. We have a library function for this, in the one-and-only itertools. listoflists = [list(range(x, 2*x)) for x in range(5)] listoflists [[], [1], [2, 3], [3, 4, 5], [4, 5, 6, 7]] from itertools import chain list(chain.from_iterable(listoflists)) [1, 2, 3, 3, 4, 5, 4, 5, 6, 7] It does exactly what it says... fast and easy-to-read. Note that I think what he really wanted is to go from a, b, c = [list(x) for x in (range(10), range(11, 20), range(21, 30))] to list(range(30)) UNDO! UNDO! UNDO! I *meant *to say: Note that I think what he really wanted is to go from a, b, c = [list(x) for x in (range(10), range(11, 20), range(21, 30))] to [a, b, c] -- http://mail.python.org/mailman/listinfo/python-list
a prob.. error in prog ..dont knw how to correct
I am new to python and have a little problem to solve .. i have an array with x, y, z co-ordinates in it as a tuple. I am trying to find the distance between each point and sorting the points according to the min distance.. i have tried a prog but m stuck bcoz of this error which I am unable to correct import cv from math import floor, sqrt, ceil from numpy import array, dot, subtract, add, linalg as lin def calcdist(data): for p in data: x = p[0] y = p[1] z = p[2] for i in range(len(data)): dist = sqrt((x[i]-x[i+1])**2 + (y[i]-y[i+1])**2 +(z[i]-z[i+1]**2)) return dist def ReadPointCloud(filename): return [tuple(map(float, l.split()[1:4])) for l in open(filename)] def main (data): for i in range(len(data)): # Finding Neighbours for j in range(len(data)): dist = calcdist(data) print dist if __name__ == '__main__': data = ReadPointCloud(r'C:\Thesis\NEHreflectance_Scanner_1_part.txt') data = data[0:100] main(data) the error m getting is... Traceback (most recent call last): File C:\Users\inshu\Desktop\cal-dist.py, line 29, in module main(data) File C:\Users\inshu\Desktop\cal-dist.py, line 22, in main dist = calcdist(data) File C:\Users\inshu\Desktop\cal-dist.py, line 11, in calcdist dist = sqrt((x[i]-x[i+1])**2 + (y[i]-y[i+1])**2 +(z[i]-z[i+1]**2)) TypeError: 'float' object has no attribute '__getitem__' -- http://mail.python.org/mailman/listinfo/python-list
pls help me with this prog
in this prog I have written a code to calculate teh centre of a given 3D data.. but i want to calculate it for every 3 points not the whole data, but instead of giving me centre for every 3 data the prog is printing the centre 3 times... import cv from math import floor, sqrt, ceil from numpy import array, dot, subtract, add, linalg as lin def CalcCentre(data): centre = array([0,0,0]) count = 0 n = 0 for p in data[n:n+3]: centre = add(centre, array(p[:3])) count += 1 centre = dot(1./count, centre) return centre n += 1 def ReadPointCloud(filename): f = open(filename) result = [] for l in f: sp = l.split() t = tuple(map(float, sp[1:4])) result.append(t) return result def main (data): j = 0 for i in data[:3]: while j != 3: centre = CalcCentre(data) j += 1 print centre if __name__ == '__main__': data = ReadPointCloud(r'Z:\data\NEHreflectance_Scanner 1_part.txt') main(data) PLS HELP -- http://mail.python.org/mailman/listinfo/python-list
