Re: Is there a graphical GUI builder?

[Steve Simmons]

On 19/02/2013 23:19, Rex Macey wrote:

I'm new to Python and only a hobbyist programmer.  A long time ago I used 
Microsoft's Visual Basic which had a nice (graphical) facility for creating 
GUIs which was part of the development environment.  I'm wondering if there's a 
utility for Python to build GUIs.  I see that there is TKinter, which is a 
scripting function to build GUIs. To be clear, I'm looking for a graphical 
interface to build GUIs. Thanks.
Take a look at Qt (and PyQt) - this includes QtDesigner, a nice GUI 
design/generation tool.  Three caveats:


1. Read and Re-read the response from Chris Angelico - IME he knows what 
he is talking about and I'm just in the process of learning first hand 
what he is telling you (I'm writing an application in Python with PyQt).
2. Qt isn't 'free' (depending on what you are going to be doing with it) 
- read the licensing rules.
3. QtDesigner isn't Visual Studio and creating a GUI in Qt/PyQt tends to 
be a process of GUI design, GUI code generation and integration with 
your 'business logic.'  There's no round-trip-engineering, so if you 
mess with your GUI code after generating it, it isn't easy to get it 
back into QtDesigner.


Steve Simmons
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Re: Import Json web data source to xls or csv

[io]

Hi Michael (name of my son) and thanks for the big help.

I'm starting to love python sintax (did they call it python for the slim 
it is compared to other languages?)

Your code didn't work immediatley as it was givin an indentation error 
that i sorted out quickly fixing the last two lines.

It worked like a charm!  :-)

About your suggestions, i tried datanitro but that it only for excel and 
seems to not work under linux on playonlinux (as no linux support is 
given)

I haven't tried the other solution you suggested, i will give it a try as 
soon as possible.

What i'm trying to do is find a new programming language that can 
integrate with softwares like libre office cal or openoffice cal or excel 
as i had my prg working on windows and vba didn't have any issues, but 
now that i moved and try to do all on linux vba isn't 100 percent working 
and many system calls cannot be done.

Do you know any place where i can start learning seriously python on the 
web?


Last question : how can i set a condition in order to exclude from 
importing those rows that have both bid and ask values = none?
I'll try to figure it out in the meantime but i'm a noob so any help will 
be appreciated.

I actually started using SPE and have winpdb installed on my linux box.

Thanks again for all the help.



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Re: Import Json web data source to xls or csv

[Cousin Stanley]

io wrote:

> 
> How do i manage to read the data source 
> from http://bitcoincharts.com/t/markets.json
> 
> I just need currency, symbol, bid, ask, volume
> 

  Following is a simple way load the json data
  and write the desired fields to a  .csv  file


import json
import urllib

url= "http://bitcoincharts.com/t/markets.json";

response   = urllib.urlopen( url ) ;

data   = json.loads( response.read() )

list_dicts = [ dict( this ) for this in data ]

f  = open( 'markets.csv' , 'w' ) 

for this_dict in list_dicts :

currency  = str( this_dict[ 'currency'] )
symbol= str( this_dict[ 'symbol' ] )
bid   = str( this_dict[ 'bid' ] )
ask   = str( this_dict[ 'ask' ] )
volume= str( this_dict[ 'volume' ] )

this_list = [ currency , symbol , bid , ask , volume ]

this_str  = ','.join( this_list )

f.write( this_str + '\n' )

f.close()
  

-- 
Stanley C. Kitching
Human Being
Phoenix, Arizona

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Re: Awsome Python - chained exceptions

[alex23]

On Feb 20, 3:14 am, rusi  wrote:
> How do you "revert to old interface"?
> So far I have managed to keep to the old by
> - logging out of gmail
> - reload GG -- now the choice to revert should appear
>
> It seems everyone does not get that option

In an amazing piece of software engineering, you need to accept the
new interface _before_ the revert to old interface option appears.

I have to do this at irregular intervals, not entirely sure what
triggers its decision to foist the new crap onto me. Now I mostly use
the feedback box to vent my spleen :)
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Re: Differences creating tuples and collections.namedtuples

[Chris Angelico]

On Wed, Feb 20, 2013 at 2:38 PM, Terry Reedy  wrote:
> Liskov Substitution Principle (LSP): I met this over 15 years ago reading
> debates among OOP enthusiasts about whether Rectangle should be a subclass
> of Square or Square a subclass of Rectangle, and similarly, whether Ostrich
> can be a legitimate subclass of Bird.
>
> The problem I see with the LSP for modeling either abstract or concrete
> entities is that we in fact do define subclasses by subtraction or
> limitation, as well as by augmentation, while the LSP only allows the
> latter.

A plausible compromise is to demand LSP in terms of programming, but
not necessarily functionality. So an Ostrich would have a fly() method
that returns some kind of failure, in the same way that any instance
of any flying-bird could have injury or exhaustion that prevents it
from flying. It still makes sense to attempt to fly - an ostrich IS a
bird - but it just won't succeed.

ChrisA
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Re: encoding error

[Terry Reedy]

On 2/19/2013 8:07 PM, halagamal2...@gmail.com wrote:

UnicodeEncodeError: 'decimal' codec can't encode character u'\ufeff'
in position 0: invalid decimal Unicode string


I believe that is a byte-order mark, which should only be the first 2 
bytes in the file and which should be removed if you use the proper 
decoder when reading the file, before parsing it.


You did not say what version of Python you used, but I would use 3.3 or 
if not that, 3.2 if possible.

http://pypi.python.org/pypi/Whoosh/
claims that whoosh works with python 3.

Also, read about the basics of unicode if you have not done so yet.

--
Terry Jan Reedy

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Re: Python 3.3 vs. MSDOS Basic

[Gregory Ewing]

Chris Angelico wrote:

On Wed, Feb 20, 2013 at 7:28 AM, Serhiy Storchaka  wrote:


10-15% faster:
... num = max(range(2, M + 1), key=g) ...


Yes, but 20-30% less clear and readable. Though I do like the idea of
playing this code in the key of G Major.


On the SmartStupid, presumably.

http://wordsmith.org/board/ubbthreads.php?ubb=showflat&Number=101906

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Re: Python problem

[ach360]

Loop_variable= 1
Pi=1.0
term=0
T=1.0
While (loop_variable> 0):
 Loop_variable=Loop_variable+1
 T=T+2.0
 
If (loop_variable%2 ==0):
 Term=0;
Else:
  term=1;


If term  ==0:
 Pi=Pi- float(1/T);
Else:
   Pi=Pi+ float(1/T);


 

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Re: Python problem

[Steven D'Aprano]

On Tue, 19 Feb 2013 19:01:53 -0800, ach360 wrote:

> I'm so lost. Given the formula pi=4-4/3+4/5-4/7+4/9-4/11+.. How do I
> print a table showing approximate value of pi by computing one term4-4/3
> then two terms4-4/3+4/5, and so on.Then how many terms of the series
> before I get 3.14, 3.141, 3.1415, 3.14159. Please helps computer teacher
> literally says figure it out and doesn't help and expects a perfect
> program.this is in python 3 please give an answer I can understand and
> an example. Thanks :) :)

First, you need to know what the formula for pi actually is. You can find 
that by googling, or look it up in a maths book. You should expect 
something like

pi = sum from i=0 to infinity of 4 divided by (something)


Then you want a program to print a table that looks something like this:

i   value
0   x
1   x
2   x


etc., where the "x" will get filled in later, and the table stops at 
a certain maximum value of i. Here is a hint:


for i in range(100):
x = "calculate something"
print("%d   %s" % (i, x)


Does that get you started? Try writing some code and see how far you get.


Good luck!




> I need this right now.
> Thanks for your time.
> 
> I need this ASAP

Then you better get started straight away then. Turn off Facebook and 
Twitter and do some real work.


-- 
Steven

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Re: Is there a graphical GUI builder?

[Michael Torrie]

On 02/19/2013 07:53 PM, Roland Koebler wrote:
> Hi,
> 
>> I'm new to Python and only a hobbyist programmer.  A long time ago
>> I used Microsoft's Visual Basic which had a nice (graphical)
>> facility for creating GUIs which was part of the development
>> environment.  I'm wondering if there's a utility for Python to
>> build GUIs.
> yes, there are several, depending on the GUI-toolkit (GTK+, Qt, ...) 
> you want to use.
> 
> But I would recommend Glade and the GTK+-Toolkit. Simply search for
> Glade, GTK and Python in your favourite search engine, and you will
> find several tutorials.

I agree that on Linux GTK is pretty darn slick.  I use it for all my
little GUIs.  But on Windows, GTK, particularly under python, isn't
quite as easy to get running.  Just be forewarned.  Doesn't seem to me
that GTK on windows is being developed at the same pace as it is on Linux.

I think if the OP is on windows (which it seems like he is) then Qt with
PySide (using either QML or QtDesigner to manipulate ui files) is an
excellent choice.
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Re: Differences creating tuples and collections.namedtuples

[Terry Reedy]

On 2/18/2013 7:18 PM, Steven D'Aprano wrote:

Terry Reedy wrote:


On 2/18/2013 6:47 AM, John Reid wrote:


I was hoping namedtuples could be used as replacements for tuples
 in all instances.


This is a mistake in the following two senses. First, tuple is a class
with instances while namedtuple is a class factory that produces
classes. (One could think of namedtuple as a metaclass, but it was not
implemented that way.)



I think you have misunderstood.


Wrong, which should be evident to anyone who reads the entire paragraph 
as the complete thought exposition it was meant to be. Beside which, 
this negative ad hominem comment is irrelevant to the rest of your post 
about the Liskov Substitution Principle.


The rest of the paragraph, in two more pieces:


Second, a tuple instance can have any length and
different instances can have different lengths. On the other hand, all
instances of a particular namedtuple class have a fixed length.


In other words, neither the namedtuple object nor any namedtuple class 
object can fully substitute for the tuple class object. Nor can 
instances of any namedtuple class fully substitute for instances of the 
tuple class. Therefore, I claim, the hope that "namedtuples could be 
used as replacements for tuples in all instances" is a futile hope, 
however one interprets that hope.


>> This affects their initialization.

Part of the effect is independent of initialization. Even if namedtuples 
were initialized by iterator, there would still be glitches. In 
particular, even if John's named tuple class B *could* be initialized as 
B((1,2,3)), it still could not be substituted for t in the code below.


>>> t = (1,2,3)
>>> type(t) is type(t[1:])
True
>>> type(t)(t[1:])
(2, 3)

As far as read access goes, B effectively is a tuple. As soon as one 
uses type() directly or indirectly (by creating new objects), there may 
be problems. That is because the addition of field names *also* adds a 
length constraint, which is a subtraction of flexibility.


---
Liskov Substitution Principle (LSP): I met this over 15 years ago 
reading debates among OOP enthusiasts about whether Rectangle should be 
a subclass of Square or Square a subclass of Rectangle, and similarly, 
whether Ostrich can be a legitimate subclass of Bird.


The problem I see with the LSP for modeling either abstract or concrete 
entities is that we in fact do define subclasses by subtraction or 
limitation, as well as by augmentation, while the LSP only allows the 
latter.


On answer to the conundrums above to to add Parallelepiped as a 
superclass for both Square and Rectangle and Flying_bird as an 
additional subclass of Bird. But then the question becomes: Does obeying 
the LSP count as 'necessity' when one is trying to follow Ockham's 
principle of not multiplying classes without necessity?


--
Terry Jan Reedy

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Python problem

[ach360]

I'm so lost. Given the formula pi=4-4/3+4/5-4/7+4/9-4/11+.. How do I print 
a table showing approximate value of pi by computing one term4-4/3 then two 
terms4-4/3+4/5, and so on.Then how many terms of the series before I get 3.14, 
3.141, 3.1415, 3.14159. Please helps computer teacher literally says figure it 
out and doesn't help and expects a perfect program.this is in python 3 please 
give an answer I can understand and an example. 
Thanks :) :) 
I need this right now. 
Thanks for your time.

I need this ASAP
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Re: Python 3.3 vs. MSDOS Basic

[workshed]

On Tuesday, February 19, 2013 3:28:25 PM UTC-5, Serhiy Storchaka wrote:
> 10-15% faster:
>
>
> def f(M):
>  def g(n, cache = {1: 0}):
>  if n in cache:
>  return cache[n]
>  if n % 2:
>  m = 3 * n + 1
>  else:
>  m = n // 2
>  cache[n] = count = g(m) + 1
>  return count
>  num = max(range(2, M + 1), key=g)
>  return num, g(num)
>
> print(*f(100))

I managed another 15-20% (on my machine) with a different caching scheme.

def g(n):
cache = [1,1] + [0]*(n - 2)
longest = 0
for x in range(1, n):
num = 0
y = x
while True:
if x < n and cache[x]:
cache[y] = num + cache[x]
break
if x&1:
x = (3*x + 1)//2#Credit to Terry
num += 2
else:
x = x//2
num += 1
ans = cache.index(max(cache))
return ans, cache[ans] - 1

Python 3.2.3 (default, Oct 19 2012, 19:53:57)
[GCC 4.7.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import timeit
>>> timeit.Timer('euler014.f(10**6)', 'import euler014').timeit(10)
16.590431928634644
>>> timeit.Timer('euler014.f(10**7)', 'import euler014').timeit(1)
17.689634084701538
>>> timeit.Timer('euler014.g(10**6)', 'import euler014').timeit(10)
13.558412790298462
>>> timeit.Timer('euler014.g(10**7)', 'import euler014').timeit(1)
14.075398921966553

In this code only entries less than n (100 in the project Euler problem)
are cached, and only one is cached per run of the inner loop, which to
me would seem to me much less efficient. I supposed the advantages are no
overhead from dict lookups, function calls, or recursion, plus it uses Terry
Reedy's nice observation that one can take two steps at a time for odd
values. I would think my version uses less memory as well, since the cache
dict/list would be maximally dense for indices less than n in either scheme.

I'm still surprised that both algorithm's seem pretty much O(n) tho.
Intuitively I'd have thought mine would start to lose out with larger
numbers, given the much lower degree of caching.

With PyPy the results are more striking:

Python 2.7.2 (1.9+dfsg-1, Jun 19 2012, 23:23:45)
[PyPy 1.9.0 with GCC 4.7.0] on linux2
Type "help", "copyright", "credits" or "license" for more information.
And now for something completely different: ``Is rigobot around when the
universe ceases to exist?''
 import timeit
 timeit.Timer('euler014.f(10**6)', 'import euler014').timeit(10)
26.138880014419556
 timeit.Timer('euler014.g(10**6)', 'import euler014').timeit(10)
1.5725858211517334

I guess PyPy can JIT the iterative loop more effectively than it can the
recursion.

This is my first post on this list btw, please let me know if I screwed
anything up.

workshed
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Re: Is there a graphical GUI builder?

[Roland Koebler]

Hi,

> I'm new to Python and only a hobbyist programmer.  A long time ago I used 
> Microsoft's Visual Basic which had a nice (graphical) facility for creating 
> GUIs which was part of the development environment.  I'm wondering if there's 
> a utility for Python to build GUIs.
yes, there are several, depending on the GUI-toolkit (GTK+, Qt, ...)
you want to use.

But I would recommend Glade and the GTK+-Toolkit. Simply search
for Glade, GTK and Python in your favourite search engine, and you
will find several tutorials.

regards,
Roland
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Re: Is there a graphical GUI builder?

[duncan smith]

On 19/02/13 22:19, Rex Macey wrote:

I'm new to Python and only a hobbyist programmer.  A long time ago I used 
Microsoft's Visual Basic which had a nice (graphical) facility for creating 
GUIs which was part of the development environment.  I'm wondering if there's a 
utility for Python to build GUIs.  I see that there is TKinter, which is a 
scripting function to build GUIs. To be clear, I'm looking for a graphical 
interface to build GUIs. Thanks.



Boa Constructor perhaps (http://boa-constructor.sourceforge.net/).

Duncan
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Re: Import Json web data source to xls or csv

[Michael Herman]

First - you can use Python in Excel. http://www.python-excel.org/ or
https://www.datanitro.com/

Updated code:

import json
import urllib
import csv

url = "http://bitcoincharts.com/t/markets.json";
response = urllib.urlopen(url);
data = json.loads(response.read())

f = open("bitcoin.csv","wb")
c = csv.writer(f)

# write headers
c.writerow(["Currency","Symbol","Bid", "Ask", "Volume"])


for d in data:

c.writerow([str(d["currency"]),str(d["symbol"]),str(d["bid"]),str(d["ask"]),str(d["currency_volume"])])



On Tue, Feb 19, 2013 at 3:48 PM, io  wrote:

> Hi,
>
> i'm new to python and programming with it and so for json format.
> I have my excel 2010 program with vba that does the following :
>
> - read the data flow from http://bitcoincharts.com/t/markets.json
> - elaborate it and puts it in excel 2010 for further calculations
>
> What i'm willing to do is the same using Linux (xubuntu) and libreoffice.
>
> I thought learning python would be a smart idea for dealing with json
> format as it has a json library/module.
>
> How do i manage to read the data source from http://bitcoincharts.com/t/
> markets.json  and then place it in different cell of a new or existing
> xls worksheet?
>
> I'm trying some code with SPE but i can't sort the problem and i'm
> receiving many errors.
>
> I just need currency, symbol, bid, ask, volume
> This is the source code i was trying to use :
>
>
> import json
> import csv
> import urllib
>
> url = "http://bitcoincharts.com/t/markets.json";
> response = urllib.urlopen(url);
> data = json.loads(response.read())
>
> f = csv.writer(open('file.csv', 'wb+'))
> # use encode to convert non-ASCII characters
> for item in data:
> values = [ x.encode('utf8') for x in item['0'].values() ]
> f.writerow([item['currency'], item['high']] + values)
>
>
>
> Thanks for any help :-)
> --
> http://mail.python.org/mailman/listinfo/python-list
>
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encoding error

[halagamal2009]

i'm trying to make indexing of csv file contain arabic words
my code:
from whoosh import fields, index
import os.path
import csv
import codecs
# This list associates a name with each position in a row
columns = ["juza","chapter","verse","voc","analysis", "unvoc","root"]

schema = fields.Schema(juza=fields.NUMERIC,
   chapter=fields.NUMERIC,
   verse=fields.NUMERIC,
   voc=fields.TEXT,
   analysis=fields.KEYWORD,
   unvoc=fields.TEXT,
   root=fields.TEXT)


# Create the Whoosh index
indexname = "index"
if not os.path.exists(indexname):
  os.mkdir(indexname)
ix = index.create_in(indexname, schema)

# Open a writer for the index
with ix.writer() as writer:
  # Open the CSV file
  """fi = codecs.open('q.csv', 'rb','utf8') 
  data = fi.read() 
  fi.close() 
  f= codecs.open('mynew.csv', 'wb','utf-8') 
  f.write(data.replace('\x00', '')) 
  f.close() 
  with codecs.open("mynew.csv", "rb","utf8") as csvfile:
# Create a csv reader object for the file
csvreader = csv.reader(csvfile)"""
  with codecs.open("q.csv", "r","utf8") as csvfile:
# Create a csv reader object for the file
csvreader = csvfile.read()

# Read each row in the file
for row in csvreader:

  # Create a dictionary to hold the document values for this row
  doc = {}

  # Read the values for the row enumerated like
  # (0, "name"), (1, "quantity"), etc.
  for colnum, value in enumerate(row):

# Get the field name from the "columns" list
fieldname = columns[colnum]

# Strip any whitespace and convert to unicode
# NOTE: you need to pass the right encoding here!
try:
value = unicode(value.strip(), "utf8")
except TypeError:
 value=value.strip()
# Put the value in the dictionary
doc[fieldname] = value

  # Pass the dictionary to the add_document method
  writer.add_document(**doc)
and i got this error:
raceback (most recent call last):
  File "D:/Python27/rr.py", line 62, in 
writer.add_document(**doc)
  File "D:/Python27\whoosh\filedb\filewriting.py", line 369, in add_document
items = field.index(value)
  File "D:/Python27\whoosh\fields.py", line 466, in index
return [(txt, 1, 1.0, '') for txt in self._tiers(num)]
  File "D:/Python27\whoosh\fields.py", line 454, in _tiers
yield self.to_text(num, shift=shift)
  File "D:/Python27\whoosh\fields.py", line 487, in to_text
return self._to_text(self.prepare_number(x), shift=shift,
  File "D:/Python27\whoosh\fields.py", line 476, in prepare_number
x = self.type(x)
UnicodeEncodeError: 'decimal' codec can't encode character u'\ufeff' in 
position 0: invalid decimal Unicode string

my file is here: http://www.mediafire.com/view/?wy3asap4ba7dknl
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Re: Python 3.3 vs. MSDOS Basic

[Ian Kelly]

On Tue, Feb 19, 2013 at 5:23 PM, Alexander Blinne  wrote:
> If changed into
>
> signed int n;
>
> there is a veeery long, perhaps infinite loop.

Yes, infinite.  Here's the first such sequence encountered with a
signed 32-bit int.

[113383, 340150, 170075, 510226, 255113, 765340, 382670, 191335,
574006, 287003, 861010, 430505, 1291516, 645758, 322879, 968638,
484319, 1452958, 726479, 2179438, 1089719, 3269158, 1634579, 4903738,
2451869, 7355608, 3677804, 1838902, 919451, 2758354, 1379177, 4137532,
2068766, 1034383, 3103150, 1551575, 4654726, 2327363, 6982090,
3491045, 10473136, 5236568, 2618284, 1309142, 654571, 1963714, 981857,
2945572, 1472786, 736393, 2209180, 1104590, 552295, 1656886, 828443,
2485330, 1242665, 3727996, 1863998, 931999, 2795998, 1397999, 4193998,
2096999, 6290998, 3145499, 9436498, 4718249, 14154748, 7077374,
3538687, 10616062, 5308031, 15924094, 7962047, 23886142, 11943071,
35829214, 17914607, 53743822, 26871911, 80615734, 40307867, 120923602,
60461801, 181385404, 90692702, 45346351, 136039054, 68019527,
204058582, 102029291, 306087874, 153043937, 459131812, 229565906,
114782953, 344348860, 172174430, 86087215, 258261646, 129130823,
387392470, 193696235, 581088706, 290544353, 871633060, 435816530,
217908265, 653724796, 326862398, 163431199, 490293598, 245146799,
735440398, 367720199, 1103160598, 551580299, 1654740898, 827370449,
-1812855948, -906427974, -453213987, -1359641960, -679820980,
-339910490, -169955245, -509865734, -254932867, -764798600,
-382399300, -191199650, -95599825, -286799474, -143399737, -430199210,
-215099605, -645298814, -322649407, -967948220, -483974110,
-241987055, -725961164, -362980582, -181490291, -544470872,
-272235436, -136117718, -68058859, -204176576, -102088288, -51044144,
-25522072, -12761036, -6380518, -3190259, -9570776, -4785388,
-2392694, -1196347, -3589040, -1794520, -897260, -448630, -224315,
-672944, -336472, -168236, -84118, -42059, -126176, -63088, -31544,
-15772, -7886, -3943, -11828, -5914, -2957, -8870, -4435, -13304,
-6652, -3326, -1663, -4988, -2494, -1247, -3740, -1870, -935, -2804,
-1402, -701, -2102, -1051, -3152, -1576, -788, -394, -197, -590, -295,
-884, -442, -221, -662, -331, -992, -496, -248, -124, -62, -31, -92,
-46, -23, -68, -34, -17, -50, -25, -74, -37, -110, -55, -164, -82,
-41, -122, -61, -182, -91, -272, -136, -68, ...]
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Re: Python 3.3 vs. MSDOS Basic

[Alexander Blinne]

Am 19.02.2013 12:42, schrieb Piet van Oostrum:
> Terry Reedy  writes:
>> I find this surprising too. I am also surprised that it even works,
>> given that the highest intermediate value is about 57 billion and I do
>> not remember that Basic had infinite precision ints.
> 
> That may explain why the Basic version is faster: it gets overflow and
> then it may have taken some shortcuts.

Consider this C program

#include 

int main(void) {

  int max = 0;
  int m = 0;
  long int n;
  int count;
  int num;

  while(m<=100) {
m++;
n = m;
count = 0;

while(n != 1) {
  count++;
  if(n % 2 == 0) {
n = n / 2;
  }
  else {
n = n*3 + 1;
  }
}

if(count > max) {
  max = count;
  num = m;
}
  }

  printf("%d, %d\n", num, max);
}

If the line

long int n;

is changed into

unsigned int n;

the program runs in 0.68 sec instead of 0.79, so there is some shortcut.
If changed into

signed int n;

there is a veeery long, perhaps infinite loop.

Greetings
Alexander

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Re: Simulation of human body in movement

[Nick Mellor]

LOL thanks Rick,

I'm a movement teacher and want to demonstrate how head balance affects the 
rest of the body. I want to do something simple to start with, probably with 
blocks, hinges and springs.

Ideally I'd like the simulation to be an interactive, real-time element on a 
web page. By moving the mouse or pressing keys the user can subtly move the 
head element and watch how the rest of the body (or set of blocks) needs to 
adapt to keep balance.

I'm investigating Arboris and the Python Computer Graphics Kit.

http://cgkit.sourceforge.net/

http://pypi.python.org/pypi/arboris/0.1.0pre7

Arboris is a rigid body dynamics and contacts simulator written in python.

[snip]

Arboris is mostly useful for robotic applications and human motion studies. The 
python language makes it particularly suited for fast-paced development 
(prototyping) and education.

On Tuesday, 19 February 2013 06:25:50 UTC+11, Rick Johnson  wrote:
> Nick Mellor  gmail.com> writes:
> 
> 
> 
> > I'm looking for a fairly undetailed simulation of the human body walking and
> 
> standing. Has anyone had a go at
> 
> > this in cgkit or similar?
> 
> 
> 
> Hi nick, your question contains too many variables to provide a proper 
> response.
> 
> It would equivalent to asking:
> 
> 
> 
>  """I need a fairly ubiquitous automobile that can drive and park"""
> 
> 
> 
> Okay, but what do you intent to use the automobile /for/? 
> 
> 
> 
> If you will be transporting many people on a sleazy tour of overpriced 
> Hollywood
> 
> stars' extravagant homes you would probably need a large bus, or if you were
> 
> going to help your bum of a brother-in-law move out of the apartment he cannot
> 
> afford anymore (and unfortunately into your spare bedroom!) then you may want 
> a
> 
> pick-up truck, if however you are going to see your grandma on her deathbed 
> and
> 
> the hospital is 2000 miles away, and your absolutely phobic about flying, and
> 
> you're on a crusade to save the environment, then you might want a prius! 
> 
> 
> 
> The point is: just as there are many types of specialized automobiles for
> 
> specialized purposes there are also many "cgkits" for specialized purposes. 
> Are
> 
> you wanting to write code that is "close to the metal" like OpenGL; which 
> offers
> 
> more control and almost unlimited extensibility, or are you looking for
> 
> something very high level, like VPython; which is easy to use but quite 
> limiting.
> 
> 
> 
> You also were vague about the Level-Of-Detail. You mentioned "fairly 
> undetailed"
> 
> -- does that mean stick figures (composed of simple lines) or "marionettes";
> 
> composed of geometric primitives (say cylinders)? Or something more?
> 
> 
> 
> And what about the LOD of the hinged joints? Are we talking only articulating
> 
> hips (goose stepping)? What about shoulders, elbows and wrist; knees and 
> ankles
> 
> and toes? Perhaps something more, perhaps less?
> 
> 
> 
> But then again you used the word "simulation" so i am beginning to think you
> 
> don't want to actually code the walk loop for specific purposed, you merely 
> wish
> 
> to attain a pre-coded simulation? Then why not use a motion-capture like 
> Juhani
> 
> suggested? 
> 
> 
> 
> You supply the "What Where When and Why" and we'll supply the "How".
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Import Json web data source to xls or csv

[io]

Hi,

i'm new to python and programming with it and so for json format.
I have my excel 2010 program with vba that does the following :

- read the data flow from http://bitcoincharts.com/t/markets.json
- elaborate it and puts it in excel 2010 for further calculations

What i'm willing to do is the same using Linux (xubuntu) and libreoffice.

I thought learning python would be a smart idea for dealing with json 
format as it has a json library/module.

How do i manage to read the data source from http://bitcoincharts.com/t/
markets.json  and then place it in different cell of a new or existing 
xls worksheet?

I'm trying some code with SPE but i can't sort the problem and i'm 
receiving many errors.

I just need currency, symbol, bid, ask, volume
This is the source code i was trying to use :


import json
import csv
import urllib

url = "http://bitcoincharts.com/t/markets.json";
response = urllib.urlopen(url);
data = json.loads(response.read())

f = csv.writer(open('file.csv', 'wb+'))
# use encode to convert non-ASCII characters
for item in data:
values = [ x.encode('utf8') for x in item['0'].values() ]
f.writerow([item['currency'], item['high']] + values)



Thanks for any help :-)
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Re: Is there a graphical GUI builder?

[Miki Tebeka]

> I'm wondering if there's a utility for Python to build GUIs.
IIRC the Qt builder can generate Python code.
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Re: Verification of bank number using modulus 11

[Ian Kelly]

On Tue, Feb 19, 2013 at 3:59 PM, Morten Engvoldsen  wrote:
> But can you tell me how could i implement below
>
> "If digits 5 and 6 of the account number are zeros, the check digit is
> calculated on the 7, 8, 9 and 10th digit of the account number."
>
> which means if account number is "8601.00.17947" then check digit is
> calculate as
>
>  result = (1*5) + (7*4)+ (9*3)+(4*2)
>
> remainder = result % 11
>
> check_digit = 11 - remainder
>
> Can you tell me how can i implement this ?

After this code:

isbn = isbn[:-1]
if len(isbn) != 10:
  return False

Add:

if isbn[4:6] == "00":
isbn = isbn[6:]

And that should do it.  Thanks to the symmetry of the weights
sequence, you don't even need to change that part at all.  The zip
function will automatically truncate to the length of the shorter
input sequence.
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Re: Verification of bank number using modulus 11

[Morten Engvoldsen]

Hi Team,
Thanks for the code.
 I have altered the code with below code, it is able to validate the number
now,

def calc_checkdigit(isbn):
isbn = isbn.replace(".", "")
check_digit = int(isbn[-1])
isbn = isbn[:-1]
if len(isbn) != 10:
  return False
weights = [5, 4, 3, 2, 7, 6, 5, 4, 3, 2]
result = sum(w * (int(x)) for w, x in zip(weights, isbn))
remainder = result % 11
if remainder == 0:
   check = 0
else:
   check = 11 - remainder
return check == check_digit

calc_checkdigit(""8601.11.**17947"")


But can you tell me how could i implement below

"If digits 5 and 6 of the account number are zeros, the check digit is
calculated on the 7, 8, 9 and 10th digit of the account number."

which means if account number is "8601.00.**17947" then check digit is
calculate as

 result = (1*5) + (7*4)+ (9*3)+(4*2)

remainder = result % 11

check_digit = 11 - remainder

Can you tell me how can i implement this ?
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Re: Is there a graphical GUI builder?

[Phil]

On 20/02/13 08:19, Rex Macey wrote:

I'm new to Python and only a hobbyist programmer.  A long time ago I used 
Microsoft's Visual Basic which had a nice (graphical) facility for creating 
GUIs which was part of the development environment.  I'm wondering if there's a 
utility for Python to build GUIs.  I see that there is TKinter, which is a 
scripting function to build GUIs. To be clear, I'm looking for a graphical 
interface to build GUIs. Thanks.



I'm new to Python myself and the best IDE that I've found is Eric.

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Re: Is there a graphical GUI builder?

[Chris Angelico]

On Wed, Feb 20, 2013 at 9:19 AM, Rex Macey  wrote:
> I'm new to Python and only a hobbyist programmer.  A long time ago I used 
> Microsoft's Visual Basic which had a nice (graphical) facility for creating 
> GUIs which was part of the development environment.  I'm wondering if there's 
> a utility for Python to build GUIs.  I see that there is TKinter, which is a 
> scripting function to build GUIs. To be clear, I'm looking for a graphical 
> interface to build GUIs. Thanks.

That way of building a window tends to produce programs that port
badly to other systems. Back in the 1990s, I used to build windows
that way (mainly using VX-REXX); playing with Java applets introduced
the novel and somewhat strange idea that your window should be built
using rules and layouts, to avoid problems with button sizes, fonts,
etc, etc. Today, cross-platform code is the norm, not a curiosity, so
this method of building up a window is correspondingly more plausible.
I strongly recommend it.

You have to think about your window differently - think about what
you're putting where, rather than going visually "that looks about
right" - but the reward is that it'll look right no matter where you
run your app. As an added bonus, you don't need any sort of graphical
builder; you can just write code directly in your editor.

ChrisA
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Re: Is there a graphical GUI builder?

[Ian Kelly]

On Tue, Feb 19, 2013 at 3:19 PM, Rex Macey  wrote:
> I'm new to Python and only a hobbyist programmer.  A long time ago I used 
> Microsoft's Visual Basic which had a nice (graphical) facility for creating 
> GUIs which was part of the development environment.  I'm wondering if there's 
> a utility for Python to build GUIs.  I see that there is TKinter, which is a 
> scripting function to build GUIs. To be clear, I'm looking for a graphical 
> interface to build GUIs. Thanks.

wxFormBuilder seems to be popular and works with wxPython.  Beyond
that, you might also take a look at the "GUI Design Tools and IDEs"
list at:

http://wiki.python.org/moin/GuiProgramming
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Re: Is there a graphical GUI builder?

[Mark Lawrence]

On 19/02/2013 22:19, Rex Macey wrote:

I'm new to Python and only a hobbyist programmer.  A long time ago I used 
Microsoft's Visual Basic which had a nice (graphical) facility for creating 
GUIs which was part of the development environment.  I'm wondering if there's a 
utility for Python to build GUIs.  I see that there is TKinter, which is a 
scripting function to build GUIs. To be clear, I'm looking for a graphical 
interface to build GUIs. Thanks.



Try typing "python gui builder" into your favourite search engine.  If 
you're lucky you might find something, if not you'll have to write your 
own or do without.


--
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Mark Lawrence

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Is there a graphical GUI builder?

[Rex Macey]

I'm new to Python and only a hobbyist programmer.  A long time ago I used 
Microsoft's Visual Basic which had a nice (graphical) facility for creating 
GUIs which was part of the development environment.  I'm wondering if there's a 
utility for Python to build GUIs.  I see that there is TKinter, which is a 
scripting function to build GUIs. To be clear, I'm looking for a graphical 
interface to build GUIs. Thanks.
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Re: Python module import failed error

[Chris Angelico]

On Wed, Feb 20, 2013 at 4:45 AM,   wrote:
> The directory /home/matt/bin contains "multimode_helper.py" and this file 
> path is in the PYTHONPATH.  I still get the import error however. so now that 
> i know the file path is in PYTHONPATH but i am still getting the import error 
> i am really confused here.

Do you understand how Unix environment variables work? You're using
the 'export' command, but that doesn't make any sort of global change
- it still applies only to things done in the same session. (Actually,
your change applies only to children of the shell where you do it...
but never mind that now.) You may do better by putting the export
command into your .bashrc - that would apply to all sessions created
by your user.

ChrisA
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Re: Python 3.3 vs. MSDOS Basic

[Chris Angelico]

On Wed, Feb 20, 2013 at 7:28 AM, Serhiy Storchaka  wrote:
> 10-15% faster:
> ... num = max(range(2, M + 1), key=g) ...

Yes, but 20-30% less clear and readable. Though I do like the idea of
playing this code in the key of G Major.

ChrisA
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Re: Python module import failed error

[matt . doolittle33]

Here is the PYTHONPATH

>>> import sys
>>> sys.path
['', '/home/matt', '/users/matt/bin', '/home/matt/bin', '/Home/bin', 
'/usr/lib/python2.7', '/usr/lib/python2.7/plat-linux2', 
'/usr/lib/python2.7/lib-tk', '/usr/lib/python2.7/lib-old', 
'/usr/lib/python2.7/lib-dynload', '/usr/local/lib/python2.7/dist-packages', 
'/usr/lib/python2.7/dist-packages', '/usr/lib/python2.7/dist-packages/PIL', 
'/usr/lib/python2.7/dist-packages/gst-0.10', 
'/usr/lib/python2.7/dist-packages/gtk-2.0', 
'/usr/lib/python2.7/dist-packages/ubuntu-sso-client', 
'/usr/lib/python2.7/dist-packages/ubuntuone-client', 
'/usr/lib/python2.7/dist-packages/ubuntuone-control-panel', 
'/usr/lib/python2.7/dist-packages/ubuntuone-couch', 
'/usr/lib/python2.7/dist-packages/ubuntuone-storage-protocol', 
'/usr/lib/python2.7/dist-packages/wx-2.8-gtk2-unicode']
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Re: Verification of bank number using modulus 11

[MRAB]

On 2013-02-19 20:50, Morten Engvoldsen wrote:

Hi Team,
I am trying to verify the account number using the following algorithm:

>

"The valid account number is 11 numeric digit without seperator. Eg.
8607947 is a valid account number. All banks apply a modulus-based
method for the validation of the account structure. The 10-digit account
number is multiplied from left to right by the following weights: 5, 4,
3, 2, 7, 6, 5, 4, 3, 2. The resulting numbers are added up and divided
by 11. The remainder is subtracted from 11 and becomes the check digit.
If the remainder is 0, the check digit will be 0. If digits 5 and 6 of
the account number are zeros, the check digit is calculated on the 7, 8,
9 and 10th digit of the account number. Account numbers for which the
remainder is 1 (check digit 10) cannot be used."

>

  I am trying to validate the Norway account number using the algorithm
mentioned in the following document:
http://www.cnb.cz/miranda2/export/sites/www.cnb.cz/cs/platebni_styk/iban/download/TR201.pdf

Here is my code:
  def calc_checkdigit(isbn):
 isbn = isbn.replace(".", "")
 check_digit = int(isbn[-1])
 isbn = isbn[:-1]
 if len(isbn) != 10:
return False
 result = sum((10 - i) * (int(x) if x != 'X' else 10) for i, x in 
enumerate(isbn))
 return (result % 11) == check_digit

calc_checkdigit(""8601.11.17947"")

In my program : it is calculating 10 digit with weights 10-1, but
according to above algorithm the weights should be : 5, 4, 3, 2, 7, 6,
5, 4, 3, 2.

Could you please let me know how can i calculate the 10 digit with
weights 5, 4, 3, 2, 7, 6, 5, 4, 3, 2. I am using python 2.7.

Thanks in advance team for help..


Put the weights into a list and use 'zip' instead of 'enumerate':

sum(w * (10 if d == 'X' else int(d)) for w, d in zip(weights, isbn))

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Re: Verification of bank number using modulus 11

[Ian Kelly]

On Tue, Feb 19, 2013 at 1:50 PM, Morten Engvoldsen  wrote:
> Here is my code:
>  def calc_checkdigit(isbn):
> isbn = isbn.replace(".", "")
> check_digit = int(isbn[-1])
> isbn = isbn[:-1]
> if len(isbn) != 10:
>return False
> result = sum((10 - i) * (int(x) if x != 'X' else 10) for i, x in
> enumerate(isbn))
> return (result % 11) == check_digit
>
> calc_checkdigit(""8601.11.17947"")
>
> In my program : it is calculating 10 digit with weights 10-1, but according
> to above algorithm the weights should be : 5, 4, 3, 2, 7, 6, 5, 4, 3, 2.
>
> Could you please let me know how can i calculate the 10 digit with weights
> 5, 4, 3, 2, 7, 6, 5, 4, 3, 2. I am using python 2.7.

Use zip with the weight sequence instead of enumerate:

weights = [5, 4, 3, 2, 7, 6, 5, 4, 3, 2]
result = sum(w * (int(x) if x != 'X' else 10) for w, x in
zip(weights, isbn))

Do the account numbers actually use 'X', or is that just left over
from the ISBN algorithm?  If not, then you could replace "(int(x) if x
!= 'X' else 10)" with just "int(x)".
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Re: First attempt at a Python prog (Chess)

[Neil Cerutti]

On 2013-02-15, MRAB  wrote:
> On 2013-02-15 16:17, Neil Cerutti wrote:
>> On 2013-02-15, Oscar Benjamin  wrote:
>>> if score > best_score or best_score is None:
>>
>> You need the None check first to avoid an exception from the
>> comparison.
>
> Only in Python 3.

It is a more difficult to find bug in Python 2, which will not
even throw an exception, but instead silently do the wrong thing.

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Re: Verification of bank number using modulus 11

[Dave Angel]

On 02/19/2013 03:50 PM, Morten Engvoldsen wrote:

Hi Team,
I am trying to verify the account number using the following algorithm:

"The valid account number is 11 numeric digit without seperator. Eg.
8607947 is a valid account number. All banks apply a modulus-based
method for the validation of the account structure. The 10-digit account
number is multiplied from left to right by the following weights: 5, 4, 3,
2, 7, 6, 5, 4, 3, 2. The resulting numbers are added up and divided by 11.
The remainder is subtracted from 11 and becomes the check digit. If the
remainder is 0, the check digit will be 0. If digits 5 and 6 of the account
number are zeros, the check digit is calculated on the 7, 8, 9 and 10th
digit of the account number. Account numbers for which the remainder is 1
(check digit 10) cannot be used."

  I am trying to validate the Norway account number using the algorithm
mentioned in the following document:
http://www.cnb.cz/miranda2/export/sites/www.cnb.cz/cs/platebni_styk/iban/download/TR201.pdf

Here is my code:
  def calc_checkdigit(isbn):
 isbn = isbn.replace(".", "")
 check_digit = int(isbn[-1])
 isbn = isbn[:-1]
 if len(isbn) != 10:
return False
 result = sum((10 - i) * (int(x) if x != 'X' else 10) for i, x in
enumerate(isbn))
 return (result % 11) == check_digit

calc_checkdigit(""8601.11.17947"")

In my program : it is calculating 10 digit with weights 10-1, but according
to above algorithm the weights should be : 5, 4, 3, 2, 7, 6, 5, 4, 3, 2.

Could you please let me know how can i calculate the 10 digit with weights
5, 4, 3, 2, 7, 6, 5, 4, 3, 2. I am using python 2.7.



Without analyzing your code, the direct answer to your code would be to 
make a table, something like:


weights = [5, 4, 3, 2, 7, 6, 5, 4, 3, 2]

and multiple by weights[i]  rather than (10-i)




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Re: backporting PEP 3134 "Exception Chaining and Embedded Tracebacks" to Python 2.7

[Demian Brecht]

Zero. There are no new features being added to 2.7.

Demian Brecht
http://demianbrecht.github.com




On 2013-02-19 12:54 PM, "Piotr Dobrogost"
 wrote:

>Hi!
>
>What is a chance of backporting PEP 3134 "Exception Chaining and Embedded
>Tracebacks" to Python 2.7?
>
>
>Regards,
>Piotr Dobrogost
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backporting PEP 3134 "Exception Chaining and Embedded Tracebacks" to Python 2.7

[Piotr Dobrogost]

Hi!

What is a chance of backporting PEP 3134 "Exception Chaining and Embedded 
Tracebacks" to Python 2.7?


Regards,
Piotr Dobrogost
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Verification of bank number using modulus 11

[Morten Engvoldsen]

Hi Team,
I am trying to verify the account number using the following algorithm:

"The valid account number is 11 numeric digit without seperator. Eg.
8607947 is a valid account number. All banks apply a modulus-based
method for the validation of the account structure. The 10-digit account
number is multiplied from left to right by the following weights: 5, 4, 3,
2, 7, 6, 5, 4, 3, 2. The resulting numbers are added up and divided by 11.
The remainder is subtracted from 11 and becomes the check digit. If the
remainder is 0, the check digit will be 0. If digits 5 and 6 of the account
number are zeros, the check digit is calculated on the 7, 8, 9 and 10th
digit of the account number. Account numbers for which the remainder is 1
(check digit 10) cannot be used."

 I am trying to validate the Norway account number using the algorithm
mentioned in the following document:
http://www.cnb.cz/miranda2/export/sites/www.cnb.cz/cs/platebni_styk/iban/download/TR201.pdf

Here is my code:
 def calc_checkdigit(isbn):
isbn = isbn.replace(".", "")
check_digit = int(isbn[-1])
isbn = isbn[:-1]
if len(isbn) != 10:
   return False
result = sum((10 - i) * (int(x) if x != 'X' else 10) for i, x in
enumerate(isbn))
return (result % 11) == check_digit

calc_checkdigit(""8601.11.17947"")

In my program : it is calculating 10 digit with weights 10-1, but according
to above algorithm the weights should be : 5, 4, 3, 2, 7, 6, 5, 4, 3, 2.

Could you please let me know how can i calculate the 10 digit with weights
5, 4, 3, 2, 7, 6, 5, 4, 3, 2. I am using python 2.7.

Thanks in advance team for help..







):
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Re: Python 3.3 vs. MSDOS Basic

[Serhiy Storchaka]

On 19.02.13 20:31, Ian Kelly wrote:

On Tue, Feb 19, 2013 at 7:46 AM, Tim Daneliuk  wrote:

Are you sure you wouldn't like to share with the class?  I'd be interested
in seeing your approach...


Very well:

def collatz(n, memo):
 if n not in memo:
 if n % 2 == 0:
 next_n = n // 2
 else:
 next_n = 3 * n + 1
 memo[n] = collatz(next_n, memo) + 1
 return memo[n]

def run_collatz(upper):
 table = {1: 0}
 max_n = max(range(1, upper), key=lambda n: collatz(n, table))
 return max_n, table[max_n]


run_collatz(100)

(837799, 524)

It could certainly be optimized further, but at about 4 seconds it's
already fast enough for most purposes.


10-15% faster:

def f(M):
def g(n, cache = {1: 0}):
if n in cache:
return cache[n]
if n % 2:
m = 3 * n + 1
else:
m = n // 2
cache[n] = count = g(m) + 1
return count
num = max(range(2, M + 1), key=g)
return num, g(num)

print(*f(100))


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Re: First attempt at a Python prog (Chess)

[Ian Kelly]

On Mon, Feb 18, 2013 at 9:15 PM, Tim Roberts  wrote:
> Chris Hinsley  wrote:
>>
>>Is a Python list as fast as a bytearray ?
>
> Python does not actually have a native array type.  Everything in your
> program that looked like an array was actually a list.

How do you mean?

>>> isinstance(bytearray(b'RNBQKBNR'), list)
False
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Re: Double posts (was Re: Python module import failed error)

[matt . doolittle33]

Thanks Lele.
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Re: Python 3.3 vs. MSDOS Basic

[Ian Kelly]

On Tue, Feb 19, 2013 at 7:46 AM, Tim Daneliuk  wrote:
> Are you sure you wouldn't like to share with the class?  I'd be interested
> in seeing your approach...

Very well:

def collatz(n, memo):
if n not in memo:
if n % 2 == 0:
next_n = n // 2
else:
next_n = 3 * n + 1
memo[n] = collatz(next_n, memo) + 1
return memo[n]

def run_collatz(upper):
table = {1: 0}
max_n = max(range(1, upper), key=lambda n: collatz(n, table))
return max_n, table[max_n]

>>> run_collatz(100)
(837799, 524)

It could certainly be optimized further, but at about 4 seconds it's
already fast enough for most purposes.
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Double posts (was Re: Python module import failed error)

[Lele Gaifax]

matt.doolittl...@gmail.com writes:

> Does anyone know why i keep having these double posts?

That's because your posts carry the following headers:

  To: python-list@python.org
  Cc: python-list@python.org

or these (from a previous message):

  To: comp.lang.pyt...@googlegroups.com
  Cc: python-list@python.org

So it seems you are answering using Google Groups, *and* putting
“python-list@python.org” in the CC field. This “forum” has three heads,
one mirroring the others: whatever you send to one of the addresses is
automatically “copied” on the other sides, and viceversa; see also

  http://wiki.python.org/moin/GoogleGroupsPython

So, simply avoid adding an explicit CC field when you send your message/reply.

Hope this helps,
bye, lele.
-- 
nickname: Lele Gaifax | Quando vivrò di quello che ho pensato ieri
real: Emanuele Gaifas | comincerò ad aver paura di chi mi copia.
l...@metapensiero.it  | -- Fortunato Depero, 1929.

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Re: improving performance of writing into a pipe

[Michael Torrie]

On 02/19/2013 02:24 AM, mikp...@gmail.com wrote:
> Or rather: what would you try to catch in this particular case?

As Peter said, nothing for now.  But you seem very resistant to telling
us what exception was raised.

Though looking at your code more closely I can see that likely the error
is related to the fact that /tmp/mypipe is not an executable program.
popen (which is deprecated and replaced by the subprocess module) is for
running programs and communicating with them over pipes created by the
popen function.  So your code is not likely to ever work as it is
presently given.

Here's the bash equivalent of your code:

$ mkfifo /tmp/path
$ cat  /tmp/path

popen() (and subprocess) is the equivalent of the first bash command.
open() is the equivalent of the second line.

Do you understand the difference?

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Re: Python module import failed error

[matt . doolittle33]

 
> 
> gnuradiocompanion.py ?  And does the error message/stacktrace appear in 
> 
> the same terminal window?
> 


hi.  ok so i  am trying to run the python module (multimode_helper.py) in the 
GNU radio companion (GRC) which is sort of like an IDE which lets you organize 
code blocks by arranging them in a flow graph instead of having to write the 
code that would call the blocks in some particular order. GRC shows the import 
error in its flow graph error viewer:

Error 0:
Block - import_0_0_0 - Import(import):
  Param - Import(import):
Import "import multimode_helper as mh" failed.

The directory /home/matt/bin contains "multimode_helper.py" and this file path 
is in the PYTHONPATH.  I still get the import error however. so now that i know 
the file path is in PYTHONPATH but i am still getting the import error i am 
really confused here.

Thanks for your attention.  
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Re: Python module import failed error

[Mark Lawrence]

On 19/02/2013 16:57, matt.doolittl...@gmail.com wrote:



What is PYTHONPATH actually set to?  You can find out by running python

interactively, then


i dont know.  how do i run pythoin interactively?



Type python at a command prompt :)

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Re: Python module import failed error

[Dave Angel]

On 02/19/2013 11:57 AM, matt.doolittl...@gmail.com wrote:



What is PYTHONPATH actually set to?  You can find out by running python

interactively, then


i dont know.  how do i run pythoin interactively?



By typing the simple command  'python'
   davea@think2:~$ python
Python 2.7.3 (default, Aug  1 2012, 05:14:39)
[GCC 4.6.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>>


But since you're running some non-python program which is in turn 
launching python, perhaps you'd better give more details.  And not 
scattered over a half dozen tiny emails, but all at once.


Do you, in a single terminal, do the export, then run the 
gnuradiocompanion.py ?  And does the error message/stacktrace appear in 
the same terminal window?


Please show us just what you're running, from start to finish.  Thanks.

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Re: Python module import failed error

[matt . doolittle33]

> 
> What is PYTHONPATH actually set to?  


OK so i ran python and then :

import sys
sys.path

bash returned:

['', '/home/matt', '/users/matt/bin', '/home/matt/bin', '/Home/bin', 
'/usr/lib/python2.7', '/usr/lib/python2.7/plat-linux2', 
'/usr/lib/python2.7/lib-tk', '/usr/lib/python2.7/lib-old', 
'/usr/lib/python2.7/lib-dynload', '/usr/local/lib/python2.7/dist-packages', 
'/usr/lib/python2.7/dist-packages', '/usr/lib/python2.7/dist-packages/PIL', 
'/usr/lib/python2.7/dist-packages/gst-0.10', 
'/usr/lib/python2.7/dist-packages/gtk-2.0', 
'/usr/lib/python2.7/dist-packages/ubuntu-sso-client', 
'/usr/lib/python2.7/dist-packages/ubuntuone-client', 
'/usr/lib/python2.7/dist-packages/ubuntuone-control-panel', 
'/usr/lib/python2.7/dist-packages/ubuntuone-couch', 
'/usr/lib/python2.7/dist-packages/ubuntuone-storage-protocol', 
'/usr/lib/python2.7/dist-packages/wx-2.8-gtk2-unicode']

so the paths i have been adding are there.  should i be adding the python file 
names in the "bin" directory as well?
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Re: Awsome Python - chained exceptions

[rusi]

On Feb 19, 7:18 am, alex23  wrote:
> On Feb 18, 3:51 pm, Rick Johnson  wrote:
>
> > I apologize for this doubling of my messages and i can assure you i
> > don't do this intentionally. Proper netiquette is very important to me.
> > These double posts are another unfortunate side-effect of using the
> > buggy Google Groups web-face to read/write Usenet. I've sent feedback
> > to the Google Groups long ago and have yet to see any changes or even
> > get any replys.
>
> Weird, I'm using GG too and not seeing any doubling of my messages. I
> have reverted to using the old interface, though, so it might be a
> side-effect of the new version they're hyping, which does seem to have
> been designed by Satan himself (the way they've separated thread view
> from article view is a huge WTF). I've sent a heap of feedback to them
> as well with no response. Google don't really seem to want to hype
> Usenet as anything other than a target for blogspot spam, it appears.

How do you "revert to old interface"?
So far I have managed to keep to the old by
- logging out of gmail
- reload GG -- now the choice to revert should appear

It seems everyone does not get that option
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Re: Python module import failed error

[matt . doolittle33]

Does anyone know why i keep having these double posts?  please excuse them; i 
am a super newbie to this forum (and python obviously). 

Thanks
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Re: Python module import failed error

[matt . doolittle33]

 
> What is PYTHONPATH actually set to?  You can find out by running python 
> 
> interactively, then

i dont know.  how do i run pythoin interactively? 
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Re: Python module import failed error

[matt . doolittle33]

On Tuesday, February 19, 2013 11:44:32 AM UTC-5, Thomas Calmant wrote:
> Hi,
> 
> Do you run Python in the same terminal than where you run the export command ?
> 

no i dont. the python program looking for the modules in the ~/bin directory is 
called GNU radio companion.  
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Re: Python module import failed error

[matt . doolittle33]

On Tuesday, February 19, 2013 11:39:14 AM UTC-5, Chris Angelico wrote:> 
> 
> What exactly do you mean by "no luck"? More details would be good.
> 

The program i am using (GNU radio companion) that wants to import the modules 
from the ~/bin folder shows this error:

Block - import_0_0_0 - Import(import):
  Param - Import(import):
Import "import multimode_helper as mh" failed.

.  
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Re: Python module import failed error

[Mark Lawrence]

On 19/02/2013 16:28, matt.doolittl...@gmail.com wrote:

  My guess would be /home/matt/bin - note the leading slash.




ChrisA


correct. and in the home directory i run export 
PYTHONPATH=${PYTHONPATH}:/home/matt/bin and have had no luck?  am i using the 
wrong command?



What is PYTHONPATH actually set to?  You can find out by running python 
interactively, then


import os
os.environ['PYTHONPATH']

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Re: Python module import failed error

[Thomas Calmant]

Hi,

Do you run Python in the same terminal than where you run the export
command ?

++
Thomas

2013/2/19 

>  My guess would be /home/matt/bin - note the leading slash.
> >
> >
> >
> > ChrisA
>
> correct. and in the home directory i run export
> PYTHONPATH=${PYTHONPATH}:/home/matt/bin and have had no luck?  am i using
> the wrong command?
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>
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Re: Python module import failed error

[Chris Angelico]

On Wed, Feb 20, 2013 at 3:28 AM,   wrote:
>  My guess would be /home/matt/bin - note the leading slash.
>>
>>
>>
>> ChrisA
>
> correct. and in the home directory i run export 
> PYTHONPATH=${PYTHONPATH}:/home/matt/bin and have had no luck?  am i using the 
> wrong command?

What exactly do you mean by "no luck"? More details would be good.

ChrisA
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Re: Python module import failed error

[matt . doolittle33]

 My guess would be /home/matt/bin - note the leading slash.
> 
> 
> 
> ChrisA

correct. and in the home directory i run export 
PYTHONPATH=${PYTHONPATH}:/home/matt/bin and have had no luck?  am i using the 
wrong command?
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Re: Python module import failed error

[Chris Angelico]

On Wed, Feb 20, 2013 at 3:17 AM,   wrote:
> thats the file path.  the directory "bin" in my home directory.  in bash it 
> obviously looks like this  "~/bin" using the file system folder the path is 
> home/Home/bin.  i have tried commands like, export 
> PYTHONPATH=${PYTHONPATH}:/users/matt/bin or home/matt/bin or Home/home/bin 
> and nothing has worked.

Change to that directory, then type 'pwd'. That'll tell you the actual
path. My guess would be /home/matt/bin - note the leading slash.

ChrisA
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Re: Python module import failed error

[matt . doolittle33]

> 
> What do you mean by that path? That doesn't look like an Ubuntu/Linux
> 
> path name. Pull up a terminal (Ctrl-Alt-T should do that for you,
> 
> though I haven't used an Ubuntu since 10.10) and see if you can 'ls'
> 
> the path - once you have the real path name (it might start with
> 
> /home/your_user_name/ for instance), go back to the commands you found
> 
> on the web and try them - they'll probably work, then.
> 
thats the file path.  the directory "bin" in my home directory.  in bash it 
obviously looks like this  "~/bin" using the file system folder the path is 
home/Home/bin.  i have tried commands like, export 
PYTHONPATH=${PYTHONPATH}:/users/matt/bin or home/matt/bin or Home/home/bin and 
nothing has worked.
from what ive found on the web the Python import process is notoriously 
underspecified, notwithstanding i was under the impression that PYTHONPATH is a 
global variable that i can add directories to at anytime to tell Python where 
to look, without having to add some sort of code to every program.  is this 
impression incorrect?  is there some code i need to add to the Python program 
call the modules in the "bin" dir?  
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Re: IOerror : need urgent help

[Mark Lawrence]

On 19/02/2013 15:40, Thomas Calmant wrote:

hi

It seems you forgot to escape the escape character in the file names ('\'):
"C:\Users\inshu.chauhan\Desktop\test.arff"
=> r"C:\Users\inshu.chauhan\Desktop\test.arff"
or
=> "C:\\Users\\inshu.chauhan\\Desktop\\test.arff"

++
Thomas



Yuck :)

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Re: IOerror : need urgent help

[inshu chauhan]

On Tue, Feb 19, 2013 at 4:54 PM, MRAB  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
>> 
>>  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:
>
>
> r"C:\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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Re: Awsome Python - chained exceptions

[rurpy]

On 02/18/2013 07:18 PM, alex23 wrote:
>[...]
> Weird, I'm using GG too and not seeing any doubling of my messages. I
> have reverted to using the old interface, though, so it might be a
> side-effect of the new version they're hyping, which does seem to have
> been designed by Satan himself (the way they've separated thread view
> from article view is a huge WTF). I've sent a heap of feedback to them
> as well with no response. Google don't really seem to want to hype
> Usenet as anything other than a target for blogspot spam, it appears.

In their new interface, GG presents a checkbox for cc: addresses in 
the post being replied to.  Unchecking the "cc: pytho...@python.org"
box will prevent the double posts.
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Re: CBT code in python

[Chris Angelico]

On Wed, Feb 20, 2013 at 2:49 AM, Megha Agrawal  wrote:
> I am not getting my answer thats why I am asking.

Making repeated requests is usually not an effective way to get
information. Especially considering how brief and incomplete your
original question was, I suspect a lot of people deleted it and moved
on. Have a read of this, and follow its advice; you'll either solve
the problem yourself, or make it a lot easier (and therefore more
likely) for someone to help you:

http://www.catb.org/esr/faqs/smart-questions.html

ChrisA
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Re: IOerror : need urgent help

[MRAB]

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 
 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:

r"C:\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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Re: CBT code in python

[Megha Agrawal]

I am not getting my answer thats why I am asking.

On Tue, Feb 19, 2013 at 9:10 PM, Mark Lawrence wrote:

> On 19/02/2013 15:27, Megha Agrawal wrote:
>
>> Plsss help !!
>>
>> On Tue, Feb 19, 2013 at 12:40 AM, Megha Agrawal > > wrote:
>>
>> Hi,
>>
>> Does anybody have code for Complete Binary tree for a given no of
>> leaves??
>>
>> Thanks in advance!!
>>
>>
> Search engines are available to get your answer.  Why not use one before
> posting your question?
>
> --
> Cheers.
>
> Mark Lawrence
>
> --
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>
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Re: Facebook Graph API

[Сахнов Михаил]

You need to get token from API server before signing requests with it,
don't you?
19.02.2013 16:42 пользователь "takeshi honda"  написал:

> The following code gave me the error, "facebook.GraphAPIError: Unsupported
> operation". How can I fix this error?
>
> import facebook
> import sys;
>
> token = 'mytokenx';
>
> graph = facebook.GraphAPI(token)
> profile = graph.get_object("myusername")
> friends = graph.get_connections("myusername", "friends") # error occured
> at this line.
>
> friend_list = [friend['name'] for friend in friends['data']]
> print friend_list
> --
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>
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Re: IOerror : need urgent help

[Mark Lawrence]

On 19/02/2013 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 
 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 !!



Use a raw string for the output file name or forward instead of back 
slashes.  Explanation here 
http://docs.python.org/2/reference/lexical_analysis.html


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Re: CBT code in python

[Mark Lawrence]

On 19/02/2013 15:27, Megha Agrawal wrote:

Plsss help !!

On Tue, Feb 19, 2013 at 12:40 AM, Megha Agrawal mailto:me...@greybatter.com>> wrote:

Hi,

Does anybody have code for Complete Binary tree for a given no of
leaves??

Thanks in advance!!



Search engines are available to get your answer.  Why not use one before 
posting your question?


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Re: IOerror : need urgent help

[Thomas Calmant]

hi

It seems you forgot to escape the escape character in the file names ('\'):
"C:\Users\inshu.chauhan\Desktop\test.arff"
=> r"C:\Users\inshu.chauhan\Desktop\test.arff"
or
=> "C:\\Users\\inshu.chauhan\\Desktop\\test.arff"

++
Thomas

2013/2/19 inshu chauhan 

> 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 
> 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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>
>
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IOerror : need urgent help

[inshu chauhan]

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 
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: Facebook Graph API

[Terry Reedy]

On 2/19/2013 7:37 AM, takeshi honda wrote:

The following code gave me the error, "facebook.GraphAPIError: Unsupported 
operation". How can I fix this error?

import facebook
import sys;

token = 'mytokenx';

graph = facebook.GraphAPI(token)
profile = graph.get_object("myusername")
friends = graph.get_connections("myusername", "friends") # error occured at 
this line.


Look in the reference for GraphAPI (Facebook account login required) to 
find out what you should have written instead of 'get_connections'.



friend_list = [friend['name'] for friend in friends['data']]
print friend_list




--
Terry Jan Reedy

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Re: CBT code in python

[Megha Agrawal]

Plsss help !!

On Tue, Feb 19, 2013 at 12:40 AM, Megha Agrawal wrote:

> Hi,
>
>
> Does anybody have code for Complete Binary tree for a given no of leaves??
>
>
> Thanks in advance!!
>
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Re: Python module import failed error

[Chris Angelico]

On Wed, Feb 20, 2013 at 2:23 AM,   wrote:
> Hello all; I am using Ubuntu 12.10 and Python v2.7.3.  I am trying to add a 
> directory to the PYTHONPATH.  All of the commands I have found on the web 
> have failed.  Please help me to add a directory to the PYHONPATH.  The file 
> path is Home/home/bin.  Thanks in advance.

What do you mean by that path? That doesn't look like an Ubuntu/Linux
path name. Pull up a terminal (Ctrl-Alt-T should do that for you,
though I haven't used an Ubuntu since 10.10) and see if you can 'ls'
the path - once you have the real path name (it might start with
/home/your_user_name/ for instance), go back to the commands you found
on the web and try them - they'll probably work, then.

ChrisA
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Python module import failed error

[matt . doolittle33]

Hello all; I am using Ubuntu 12.10 and Python v2.7.3.  I am trying to add a 
directory to the PYTHONPATH.  All of the commands I have found on the web have 
failed.  Please help me to add a directory to the PYHONPATH.  The file path is 
Home/home/bin.  Thanks in advance.  
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Re: Python 3.3 vs. MSDOS Basic

[Tim Daneliuk]

On 02/18/2013 03:54 PM, Ian Kelly wrote:

On Mon, Feb 18, 2013 at 12:13 PM, John Immarino  wrote:

I coded a Python solution for Problem #14 on the Project Euler website. I was 
very surprised to find that it took 107 sec. to run even though it's a pretty 
simple program.  I also coded an equivalent solution for the problem in the old 
MSDOS basic. (That's the 16 bit app of 1980s vintage.)  It ran in 56 sec. Is 
there a flaw in my coding, or is Python really this slow in this particular 
application. MSDOS Basic usually runs at a snails pace compared to Python.


Well, I don't see anything that looks especially slow in that code,
but the algorithm that you're using is not very efficient.  I rewrote
it using dynamic programming (details left as an exercise), which got
the runtime down to about 4 seconds.



Are you sure you wouldn't like to share with the class?  I'd be interested
in seeing your approach...



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Re: improving performance of writing into a pipe

[mikprog]

> > Thanks a lot Serhiy to you and to everyone else.
> 
> 
> Do you mind telling us what fix you applied?


Oh, apologies Peter, I thought it was clear as I posted it after the lines 
written by Serhiy.
So it was what Serhiy suggest in addition to some (?minor?) modification to the 
pipe itself, which I cannot comment about as I don't have access to it.
But apparently the problem of not being able to open it was due to it.
(It does not help much I am afraid... but that's all I know).

Mik
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Re: Python 3.3 vs. MSDOS Basic

[Olive]

> max=0
> m=0
> while m<=100:
> m+=1
> count=0
> n=m
> while n!=1:
> count+=1
> if n%2==0:
> n=n//2
> else:
> n=3*n+1
> if count>max:
>  max=count
>  num=m
> print(num,max)
> 

I have tried to run your program with pypy (Python git compiler) 
(http://pypy.org/), it runs about 15x faster (8 sec instead of 2m2sec in my old 
Celeron M420 computer).

Olive

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Re: improving performance of writing into a pipe

[Peter Otten]

mikp...@gmail.com wrote:

>> def write_to_pipe(line):
>>  hexbytes = ''.join('\\x%02x' % ord(c) for c in line)

I thought this was only needed to have 'echo' except your data.

>>  with open('/tmp/mypipe', 'w') as f:
>>  f.write(hexbytes)

> Update:
> with a fix in the pipe THIS was the right way to do it, and it now works.
> Thanks a lot Serhiy to you and to everyone else.

Do you mind telling us what fix you applied?

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Re: Making unhashable object

[Peter Otten]

Olive wrote:

> I am trying to define a class whose instances should not be hashable,
> following:
> http://docs.python.org/2/reference/datamodel.html#object.__hash__
> 
> class A:
> def __init__(self,a):
> self.value=a
> __hash__=None
> 
> 
> Then:
> 
 a=A(3)
 hash(a)
> Traceback (most recent call last):
>   File "", line 1, in 
> TypeError: 'NoneType' object is not callable
 hash([2])
> Traceback (most recent call last):
>   File "", line 1, in 
> TypeError: unhashable type: 'list'
> 
> I would expect the same error in both case and the error is confusing in
> the first case. What's the proper way of making an object non hashable?
> 
> Olive

Deriving your classes from object has several advantages, among them:

>>> class A:
... __hash__ = None
... 
>>> hash(A())
Traceback (most recent call last):
  File "", line 1, in 
TypeError: 'NoneType' object is not callable
>>> class B(object):
... __hash__ = None
... 
>>> hash(B())
Traceback (most recent call last):
  File "", line 1, in 
TypeError: unhashable type: 'B'


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Re: Making unhashable object

[Chris Angelico]

On Wed, Feb 20, 2013 at 12:38 AM, Olive
 wrote:
> I am trying to define a class whose instances should not be hashable, 
> following: http://docs.python.org/2/reference/datamodel.html#object.__hash__
>
> class A:
> def __init__(self,a):
> self.value=a
> __hash__=None

This is an old-style class. If you subclass object, it works as you expect:

>>> class A(object):
def __init__(self,a):
self.value=a
__hash__=None

>>> a=A(3)
>>> hash(a)

Traceback (most recent call last):
  File "", line 1, in 
hash(a)
TypeError: unhashable type: 'A'

This is with Python 2.6. With Python 3 and later, that distinction no
longer exists.

ChrisA
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Re: Making unhashable object

[Jean-Michel Pichavant]

- Original Message -
> I am trying to define a class whose instances should not be hashable,
> following:
> http://docs.python.org/2/reference/datamodel.html#object.__hash__
> 
> class A:
> def __init__(self,a):
> self.value=a
> __hash__=None
> 
> 
> Then:
> 
> >>> a=A(3)
> >>> hash(a)
> Traceback (most recent call last):
>   File "", line 1, in 
> TypeError: 'NoneType' object is not callable
> >>> hash([2])
> Traceback (most recent call last):
>   File "", line 1, in 
> TypeError: unhashable type: 'list'
> 
> I would expect the same error in both case and the error is confusing
> in the first case. What's the proper way of making an object non
> hashable?
> 
> Olive

Try

class A:
  def __hash__(self):
raise TypeError("unhashable type: '%s'" % self.__class__.__name__)

JM


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Making unhashable object

[Olive]

I am trying to define a class whose instances should not be hashable, 
following: http://docs.python.org/2/reference/datamodel.html#object.__hash__

class A:
def __init__(self,a):
self.value=a
__hash__=None


Then:

>>> a=A(3)
>>> hash(a)
Traceback (most recent call last):
  File "", line 1, in 
TypeError: 'NoneType' object is not callable
>>> hash([2])
Traceback (most recent call last):
  File "", line 1, in 
TypeError: unhashable type: 'list'

I would expect the same error in both case and the error is confusing in the 
first case. What's the proper way of making an object non hashable?

Olive

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Re: improving performance of writing into a pipe

[mikprog]

> 
> def write_to_pipe(line):
> 
>  hexbytes = ''.join('\\x%02x' % ord(c) for c in line)
> 
>  with open('/tmp/mypipe', 'w') as f:
> 
>  f.write(hexbytes)


Update:
with a fix in the pipe THIS was the right way to do it, and it now works.
Thanks a lot Serhiy to you and to everyone else.

Mik

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ANN: pyftpdlib 1.0.0 released

[Giampaolo Rodolà]

Hi there guys,
After 1 year of development and refinements I'm pleased to announce a
release of pyftpdlib which appears to be the fastest FTP server out
there (on UNIX at least)! See:
http://code.google.com/p/pyftpdlib/wiki/Benchmarks

1.0.0 release introduces serious improvements amongst which python 3
support (finally!) and full Unicode support.  Here's the major ones.


=== New IO loop and epoll() / kqueue() support ===

The IO loop, originally relying on asyncore, has been rewritten from
scratch 
(http://code.google.com/p/pyftpdlib/source/browse/trunk/pyftpdlib/ioloop.py)
and now supports epoll() on Linux and kqueue() on OSX/BSD.
Also select() (Windows) and poll() pollers have been rewritten
resulting in pyftpdlib being an order of magnitude faster and more
scalable than ever. Read the full story here:
http://code.google.com/p/pyftpdlib/issues/detail?id=203

=== Alternative concurrency model ===

It is now possible to change the default concurrency model from async
(non blocking) to multiple processes / threads based, meaning you are
now free to block as long as you want and support particularly slow
filesystems.
Switching is as easy as changing an import. More information are here:
http://code.google.com/p/pyftpdlib/wiki/Tutorial#4.6_-_Changing_the_concurrency_model

=== Python 3 porting + full Unicode support ===

Finally!

=== Logging ===

logging module is now used for logging as replacement for log(),
logline() and logerror() functions which are now deprecated. Also, the
whole logging infrastructure has been refactored and it is more
compact and consistent. Also by default pyftpdlib logs will have
colors.

=== Other improvements ===

 * a new FilesystemError exception class is available in order send
   custom error strings to client from an AbstracteFS subclass.

 * on_connect() and on_disconnect() callbacks

 * FTPHandler.ftp_* methods implementing filesystem-related commands
   now return a meaningful value on success (tipically the path name).

 * FTPServer.serve_forever() has a new handle_exit parameter which
   can be set to False in order to avoid handling SIGTERM/SIGINT signals.

=== Backward compatibility breakage ===

A lot of backward incompatible changes have been introduced amongst
which the different import system, the different
validate_authentication() signature and the fact that the filesystem
class now expects Unicode strings rather than bytes. HISTORY file
enlists all of them and also provides a guide on how to port your
existent to this new version.
http://code.google.com/p/pyftpdlib/source/browse/trunk/HISTORY?spec=svn1175&r=1172#85


=== Some links ===

Home: http://code.google.com/p/pyftpdlib/
Download: http://code.google.com/p/pyftpdlib/list/downloads
Tutorial: http://code.google.com/p/pyftpdlib/wiki/Tutorial
Complete list of changes:
http://code.google.com/p/pyftpdlib/source/browse/trunk/HISTORY


That should be all folks.
I hope you'll enjoy this new version,

Giampaolo Rodola'
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Re: Data Tree urgent help!!!!!!

[Ana Dionísio]

Thank you so much!!! It works perfectly!!!

;)
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Facebook Graph API

[takeshi honda]

The following code gave me the error, "facebook.GraphAPIError: Unsupported 
operation". How can I fix this error?

import facebook
import sys;

token = 'mytokenx';

graph = facebook.GraphAPI(token)
profile = graph.get_object("myusername")
friends = graph.get_connections("myusername", "friends") # error occured at 
this line.

friend_list = [friend['name'] for friend in friends['data']]
print friend_list
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Re: Data Tree urgent help!!!!!!

[Peter Otten]

anadionisio...@gmail.com wrote:

> Hello!
> I have this lists with information and I need to make a "tree" by
> associating the information inside the lists. For example:
> 
> l1 = [apple, pear]
> l2 = [dog, cat]
> l3 = [fork, spoon]
> 
> And I need to make something like this:
> 
> l4 = [apple, dog, fork]
> l5 = [apple, dog, spoon]
> l6= [apple, cat, fork]
> l7 = [apple, cat, spoon]
> l8 = [pear, dog, fork]
> etc...
> 
> How can I do this? I could use "for" cycles and "if...else" but with
> larger lists it gets complicated
> 
> Is there some simple solution that I can use?

Try itertools.product():

>>> class Name(str):
... def __repr__(self):
... return self
... 
>>> apple, pear, dog, cat, fork, spoon = map(Name, "apple pear dog cat fork 
spoon".split())
>>> fruit = [apple, pear]
>>> pets = [dog, cat]
>>> cutlery = [fork, spoon]
>>> from itertools import product
>>> for item in product(fruit, pets, cutlery):
... print item
... 
(apple, dog, fork)
(apple, dog, spoon)
(apple, cat, fork)
(apple, cat, spoon)
(pear, dog, fork)
(pear, dog, spoon)
(pear, cat, fork)
(pear, cat, spoon)



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Data Tree urgent help!!!!!!

[anadionisio257]

Hello! 
I have this lists with information and I need to make a "tree" by associating 
the information inside the lists. For example:

l1 = [apple, pear]
l2 = [dog, cat]
l3 = [fork, spoon]

And I need to make something like this:

l4 = [apple, dog, fork]
l5 = [apple, dog, spoon]
l6= [apple, cat, fork]
l7 = [apple, cat, spoon]
l8 = [pear, dog, fork]
etc...

How can I do this? I could use "for" cycles and "if...else" but with larger 
lists it gets complicated   

Is there some simple solution that I can use?

I hope you could help me  
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Re: improving performance of writing into a pipe

[mikprog]

On Monday, February 18, 2013 7:29:09 PM UTC, Serhiy Storchaka wrote:
> On 18.02.13 17:12, mikp...@gmail.com wrote:
> 
> > on an embedded linux system (BeagleBoard) I am writing data coming from 
> > bluetooth dongle into a pipe.
> 
> > The function is the following one:
> 
> >
> 
> >
> 
> > def write_to_pipe(line):
> 
> >
> 
> >  # next line ensures that bytes like '0x09' are not translated into 
> > '\t' for
> 
> >  #example, and they are sent as such
> 
> >  hexbytes = "\\x" + "\\x".join([hex(ord(c))[2:].zfill(2) for c in line])
> 
> >  wrap = ["echo -en '", "' > /tmp/mypipe"]
> 
> >  msg = hexbytes.join(wrap)
> 
> >  print "DBG: sending: ", msg
> 
> >
> 
> >  try:
> 
> >  os.popen( msg )
> 
> >  except:
> 
> >  print "Error: write_to_pipe has failed!"
> 
> >
> 
> >
> 
> > Now I typically receive 4 bytes from the bluetooth dongle and that is fine.
> 
> > However when I receive many more than that it seems that the writing into 
> > the pipe is too slow.
> 
> >
> 
> > Is there any clever/obvious way to improve the code above?
> 
> > (I am quite sure there is to be honest).
> 
> 
> 
> def write_to_pipe(line):
> 
>  hexbytes = ''.join('\\x%02x' % ord(c) for c in line)
> 
>  with open('/tmp/mypipe', 'w') as f:
> 
>  f.write(hexbytes)


I'll take your hexbytes = '' line (which is surely more efficient than mine).
However whit this approach open + write it seems the pipe doesn't get the 
data...
I am not sure what is going on. 
At this point I suspect it could be a problem on the pipe itself (which I 
inherited). 

It is just weird that the pipe accept this correctly:
wrap = ["echo -en '", "' > /tmp/midi"]
msg = hexbytes.join(wrap)
os.popen( msg )

but seems to be careless of approach open + write.

I need to investigate there.

Thanks a lot, to you and to everyone else.
Mik

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Re: Python 3.3 vs. MSDOS Basic

[Piet van Oostrum]

Terry Reedy  writes:

> On 2/18/2013 2:13 PM, John Immarino wrote:
>> I coded a Python solution for Problem #14 on the Project Euler
>> website. I was very surprised to find that it took 107 sec. to run
>> even though it's a pretty simple program.  I also coded an equivalent
>> solution for the problem in the old MSDOS basic. (That's the 16 bit
>> app of 1980s vintage.)  It ran in 56 sec. Is there a flaw in my
>> coding, or is Python really this slow in this particular application.
>> MSDOS Basic usually runs at a snails pace compared to Python.
>
> I find this surprising too. I am also surprised that it even works,
> given that the highest intermediate value is about 57 billion and I do
> not remember that Basic had infinite precision ints.

That may explain why the Basic version is faster: it gets overflow and
then it may have taken some shortcuts.
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Re: improving performance of writing into a pipe

[Oscar Benjamin]

On 19 February 2013 10:27,   wrote:
>> can work. As a few people already told you the built-in open()
>
>
> Few people?
> I thought Oscar was a singular person, not a group of people :-)

Serhiy also suggested it.

> Seriously, I am convinced by that approach (thanks) and I wish to go that 
> way, but the problem I am getting now is that the open fails and then I can't 
> go on.

Perhaps no-one has been explicit enough about what you should do here:

1) Remove all try/except from your code.
2) Run the code
3) Look at the *unadulterated* error message that Python prints out
4) Either fix the error if you know how or
5) Reply here posting the exact error message.

Also, in future:
6) Don't use bare try/except and don't catch errors while you're
debugging. Allow the errors to be printed as they are so that you can
read the message and see the line that triggers the error.
7) Don't post to a mailing list saying "I get an error", "I can see
errors" or "it doesn't work". If you have errors paste the exact error
message (all of it!). If you don't get errors but it doesn't do what
you want explain exactly what happened and also what you wanted to
happen. If you had followed this procedure at the start of this
thread, then you would already have a solution to (or at least an
explanation of) your problem by now.

> Also, I am now looking at the subprocess as os.popen seems deprecated.
> Any opinion on that?

I'm not convinced that either is appropriate for your problem.


Oscar
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Re: Python 3.3 vs. MSDOS Basic

[Serhiy Storchaka]

On 18.02.13 21:13, John Immarino wrote:

max=0
m=0
while m<=100:
 m+=1
 count=0
 n=m
 while n!=1:
 count+=1
 if n%2==0:
 n=n//2
 else:
 n=3*n+1
 if count>max:
  max=count
  num=m
print(num,max)


Some minor tips:

1. Use range() for m iteration.
2. Instead of "if n%2==0:" use just "if n%2:".
3. Convert all you code to a function. Python is a little faster with 
locals than with globals.


In sum all this tips will speedup your code about 2x.

And one big tip:

Use cashing (and recursion). This will speedup your code more than 10x.


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Re: Python 3.3 vs. MSDOS Basic

[Anssi Saari]

John Immarino  writes:

> I coded a Python solution for Problem #14 on the Project Euler
> website. I was very surprised to find that it took 107 sec. to run
> even though it's a pretty simple program.  I also coded an equivalent
> solution for the problem in the old MSDOS basic. (That's the 16 bit
> app of 1980s vintage.)

Just out of curiosity, can you post the basic version as well?
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Re: improving performance of writing into a pipe

[mikprog]

> 
> Once you get your script working you can try to provoke errors, and for 
> 
> those errors you can recover from you can write error handlers. For IOError 
> 
> and Python < 3.3 that may involve inspecting the errno attribute and 
> 
> conditionally reraising.


Ok.



> By the way, I don't think
> 
> 
> >> > PIPEPATH = ["/tmp/mypipe"]
> 
> >> > self.process = os.popen( self.PIPEPATH, 'w')
> 
> 
> 
> can work. As a few people already told you the built-in open()


Few people?
I thought Oscar was a singular person, not a group of people :-)
Seriously, I am convinced by that approach (thanks) and I wish to go that way, 
but the problem I am getting now is that the open fails and then I can't go on.

Also, I am now looking at the subprocess as os.popen seems deprecated.
Any opinion on that?
Thanks for your suggestion.

Mik
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Re: Instances as dictionary key, __hash__ and __eq__

[Jean-Michel Pichavant]

> > Additionally, If I'm making things much more complicated than they
> > need to be, let me know.
> 

> You are. There are ways to achieve what you want, but it requires a
> lot more setup and discipline. The simplest way is probably to have
> a _equal_fields() method that subclasses override, returning a tuple
> of the attributes that should be hashed. Then in __hash__() and
> __eq__ you iterate over the returned tuple, get the value for each
> attribute and either hash or compare.

> Of course, you have to take into account in __eq__ that the other
> instance may not have the same attributes (e.g. self is a subclass
> that uses extra attributes in its __hash__ and __eq__).

> Tim Delaney

I will happily restrain myself to never subclass such class.

JM


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Re: improving performance of writing into a pipe

[Peter Otten]

mikp...@gmail.com wrote:

> On Monday, February 18, 2013 6:12:01 PM UTC, Michael Torrie wrote:
>> On 02/18/2013 10:00 AM, mikp...@gmail.com wrote:
>> 
>> > [..]
>> 
>> >>
>> 
>> >> I don't see an exception in your answer. Where did you put it for us?
>> 
>> >>
>> 
>> > 
>> 
>> > well I just did print a message:
>> 
>> > 
>> 
>> > PIPEPATH = ["/tmp/mypipe"]
>> 
>> > 
>> 
>> > [..]
>> 
>> > try:
>> 
>> > self.process = os.popen( self.PIPEPATH, 'w')
>> 
>> > except:
>> 
>> > print "Error while trying opening the pipe!"
>> 
>> > print "check: ", self.PIPEPATH
>> 
>> > exit()
>> 
>> > 
>> 
>> > I see the error messages.
>> 
>> 
>> 
>> Unfortunately your attempt to catch this exception is hiding the true
>> 
>> cause.  You need to give us the actual exception.  Otherwise it could be
>> 
>> anything from self.PIPEPATH not existing to who knows what.
>> 
>> 
>> 
>> Almost never do you want to catch all exceptions like you're doing.  You
>> 
>> should only catch the specific exceptions you know how to deal with in
>> 
>> your code.
>> 
>> 
>> 
>> For testing purposes, if your code really is as you put it, then
>> catching exceptions is kind of silly since you're just re-raising the
>> exception (sort of) but without any contextual information that would
>> make the error meaningful.
> 
> 
> Ok, I get your point.
> But on the other hand how do I know what to catch if I have no clue what
> is causing the error? There must be a way to catch all the possible errors
> and then investigate what is the problem, right? (which is not what I have
> done so far).
> 
> Or rather: what would you try to catch in this particular case?

Nothing. 

Once you get your script working you can try to provoke errors, and for 
those errors you can recover from you can write error handlers. For IOError 
and Python < 3.3 that may involve inspecting the errno attribute and 
conditionally reraising.

By the way, I don't think

>> > PIPEPATH = ["/tmp/mypipe"]
>> > self.process = os.popen( self.PIPEPATH, 'w')

can work. As a few people already told you the built-in open()

with open(PIPEPATH, "w") as f:
   f.write(...)

is the way to go.



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Re: Differences creating tuples and collections.namedtuples

[Steven D'Aprano]

On Mon, 18 Feb 2013 23:48:46 -0800, raymond.hettinger wrote:

[...]
> If your starting point is an existing iterable such as s=['Guido',
> 'BDFL', 1], you have a couple of choices:   p=Person(*s) or
> p=Person._make(s).  The latter form was put it to help avoid unpacking
> and repacking the arguments.


It might not be obvious to the casual reader, but despite the leading 
underscore, _make is part of the public API for namedtuple:

http://docs.python.org/2/library/collections.html#collections.namedtuple



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Steven
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Re: Differences creating tuples and collections.namedtuples

[Steven D'Aprano]

On Mon, 18 Feb 2013 23:48:46 -0800, raymond.hettinger wrote:

[...]
> If your starting point is an existing iterable such as s=['Guido',
> 'BDFL', 1], you have a couple of choices:   p=Person(*s) or
> p=Person._make(s).  The latter form was put it to help avoid unpacking
> and repacking the arguments.


It might not be obvious to the casual reader, but despite the leading 
underscore, _make is part of the public API for namedtuple:

http://docs.python.org/2/library/collections.html#collections.namedtuple



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Steven
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Re: Differences creating tuples and collections.namedtuples

[Steven D'Aprano]

Pardon me for the double-post, if any, my news client appears to have 
eaten my first reply.

On Mon, 18 Feb 2013 23:48:46 -0800, raymond.hettinger wrote:

[...]
> If your starting point is an existing iterable such as s=['Guido',
> 'BDFL', 1], you have a couple of choices:   p=Person(*s) or
> p=Person._make(s).  The latter form was put it to help avoid unpacking
> and repacking the arguments.


It might not be obvious to the casual reader, but despite the leading 
underscore, _make is part of the public API for namedtuple:

http://docs.python.org/2/library/collections.html#collections.namedtuple



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Steven
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