Re: A new to Python question
On 2005-05-14, M.E.Farmer wrote: > I explained what i meant in previous post there was nothing more than > just a discussion No. You claimed This will only create a tuple in memory But we just learned that this is not the case. > I have no real problem here just more of a sore point in style for > me. I feel that parens are quite overloaded and it can be confusing > to newbies. But if the parens are just fluff then get rid of them, it > is clearer * at least to me * ;) Reduced to this argument I have no objection. > There are enough things wrapped in parens nowadays it is starting to > look like lisp. Lisp is far from being ugly ;-) Bernd -- Those who desire to give up freedom in order to gain security, will not have, nor do they deserve, either one. [T. Jefferson] -- http://mail.python.org/mailman/listinfo/python-list
Re: space saving retitle of thread
Johnny Gentile wrote: > aa. I just added a second monitor and have over two feet of monitor as 1280 x 1024. Outlook expands this message and it still runs off the right side of the second monitor. -- http://mail.python.org/mailman/listinfo/python-list
Paranoider Deutschenmoerder kommt in Psychiatrie
Lese selbst: http://brandenburg.rz.fhtw-berlin.de/poetschke.html -- http://mail.python.org/mailman/listinfo/python-list
In search of prothon source
Since the DNS servers hosting prothon.org have stopped responding, the sole source of the source of prothon online that I can find has become inaccessable. I was wondering if anyone subscribed has a copy of the source for the last C version of prothon, and would be kind enough to post a copy online. Thanks, Alex -- http://mail.python.org/mailman/listinfo/python-list
Re: converting a set into a sorted list
Thank you for the pointer. I'll upgrade to 2.4. Best, Mack -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
Bernd Nawothnig wrote:
> > You're thinking you're passing the arguments as reference
>
> That is the way Fortran handles them:
which is one of the things you really love when you link against
underdocumented Fortran programs from C. ("is that parameter
a scalar or an array? crash! oh, an array. how many values does
it expect? crash! oh, a few more, I suppose").
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Re: pygame on win32, image.fromstring()
tlviewer wrote:
> Next I'm going to load all 53 card resources into a list (array) of
> strings, then write it out, pickled. That should smooth out loading the
>game when I use 4-6 decks (Blackjack-21).
# -*- coding: cp1252 -*-
"""
keywords: resource bitmap pickle
description: pickle resources from cards.dll
requires:
Pygame from www.pygame.org,
PIL from www.pythonware.com/products/pil/
WinXP out:
63 ioerror
64 ioerror
66 resource skipped
saving pickled list
closing
debugging
"""
# imports
import win32api as wi
import string as st
import pygame as gm
import Image as im
import StringIO
import win32con as wc
import os, sys
import pickle as pkl
# OS independent path -- win32 only
sysroot = os.environ.get('SYSTEMROOT')
# get module handle for cards DLL
hnd = wi.LoadLibrary(sysroot + '/system32/cards.dll')
"""
Loadresource returns the card image without a header! I dumped these
header strings from ResourceHacker. There are only 2 kinds: one for the
pictures, and one for Ace+numbers.
"""
# this header works for 71x96x1BPP image
pic_header = [ chr(0x42), chr(0x4D), chr(0xDE), chr(0x0D), chr(0x00), \
chr(0x00), chr(0x00), chr(0x00), chr(0x00), chr(0x00), chr(0x4A), \
chr(0x00), chr(0x00), chr(0x00)]
num_header = [ chr(0x42), chr(0x4D), chr(0xA0), chr(0x04), chr(0x00), \
chr(0x00), chr(0x00), chr(0x00), chr(0x00), chr(0x00), chr(0x20), \
chr(0x00), chr(0x00), chr(0x00)]
fname = 'pkl_deck.dat'
fname = os.curdir + '/' + fname
debugr=1
#init main array to hold the cards as strings
arr_cards=[]
def cards(fname):
#sheader = ''.join([ chr(header[x]) for x in range(len(header))])
if debugr!=0:
str = wi.LoadResource( hnd, 2, 1, 1033)
str = st.join(num_header,'') + str
fp = open( os.curdir + '/aceclub.bmp', "wb")
fp.write( str)
fp.close ()
for i in range(1,68):
#default header (num)
#print "fetch ", i
header = num_header
if i % 13 > 10:
header = pic_header
try:
str = wi.LoadResource( hnd, wc.RT_BITMAP, i, 1033)
except:
print "%d" % i, " resource skipped"
continue
str = st.join(header,'') + str
try:
obj = im.open(StringIO.StringIO(str))
arr_cards.insert(i,obj.tostring())
except IOError:
print "%d" % i, " ioerror"
pass
wi.FreeLibrary(hnd)
#
# pickle out the list
print "saving pickled list"
fp = open(os.curdir + '/pkl_deck.dat', "wb")
try:
pkl.dump( arr_cards, fp, 1) #binary size Win2k:312kB WinXP:445kB
except:
print "errored, but still closing file"
fp.close()
else:
print "closing"
fp.close()
#fp = open("e:/batch/msdn/Bitmap_11.bmp", "rb")
## main ##
# retrieve the deck from our pickled list, or repickle the list to file
if not os.path.exists(fname):
cards(fname)
else:
fp = open(os.curdir + '/pkl_deck.dat','rb')
val=fp.read()
print "pickled list len=",len(val)
fp.close
arr_cards=pkl.loads(val)
if debugr!=0:
img = gm.image.fromstring(arr_cards[11],(71,96),"P")
print "debugging",img, img.get_rect()
--
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Re: A new to Python question
M.E.Farmer wrote: > I said exactly what I meant, the parentheses around the values creates > a tuple that you have no reference to! repeating it doesn't make you right; no extra tuple is created, and the parens are part of the syntax: If the target is a target list enclosed in parentheses or in square brackets: The object must be a sequence with the same number of items as there are targets in the target list, and its items are assigned, from left to right, to the corresponding targets. http://docs.python.org/ref/assignment.html (originally, you had to use [] to unpack lists, and () or no parens only worked for tuples. the ability to use an arbitrary sequence was added in 1.5) on the other hand, the function you're calling in this example *does* create a tuple that you have no reference to after the assignment. that doesn't matter, of course, since the tuple is removed by the garbage collector immediately after it has been unpacked. -- http://mail.python.org/mailman/listinfo/python-list
Re: Modifying a built-in function for logging purposes
[EMAIL PROTECTED] wrote: > I wonder if it is possible to change (temporarily) a built-in function > for logging purposes. > Let me explain: > I want to log all the 'open' operations, recording the file to be > opened, the "mode" (r/w/a...) and (possibly) the module which made the > call. import sys import __builtin__ # note: no plural s old_open = __builtin__.open def myopen(*args): code = sys._getframe(1).f_code print "OPEN", args, "FROM", code.co_name, "IN", code.co_filename return old_open(*args) __builtin__.open = myopen this only handles file opens that goes via the "open" function, of course. to handle all opens, including internal operations (e.g. imports), you're probably better off using an external tool (e.g. strace, filemon, or some- thing similar). -- http://mail.python.org/mailman/listinfo/python-list
Re: Faster GUI text control
"none <"@bag.python.org> wrote: > > no, it would mean writing some python code. if all you need is a scrolling > > text list, you can simply use the code on this page: > > > > http://effbot.org/zone/wck-4.htm > > > > (see "A scrollable list view, with scrollbar support" and, optionally, > > the virtual data modifications under "Displaying Huge Data Sets") > > > > the resulting widget will update at constant speed, independent of the > > data size. > > > > > > Thanks for the suggestion. I looked at that, but I need to be able to > selectively change colors on parts of the text and I didn't think I > could do that with a list box. Am I misunderstanding that? yes. the list view isn't a listbox, it's a new widget. with the list view, you control the drawing yourself, and can draw things in whatever way you want. (the section "Non-Standard Rendering" talks about this; reading http://effbot.org/zone/wck-3.htm also helps). -- http://mail.python.org/mailman/listinfo/python-list
Re: incorrect(?) shlex behaviour
bill wrote:
> Consider:
> >>> import shlex
> >>> shlex.split('$(which sh)')
> ['$(which', 'sh)']
>
> Is this behavior correct? It seems that I should
> either get one token, or the list
> ['$','(','which','sh',')'],
> but certainly breaking it the way it does is
> erroneous.
>
> Can anyone explain why the string is being split
> that way?
This may help.
http://www.python.org/dev/doc/devel/lib/module-shlex.html
This works on Python 2.4:
>>> import shlex
>>> sh = shlex.shlex('$(which sh)')
>>> sh.get_token()
'$'
>>> sh.get_token()
'('
>>> sh.get_token()
'which'
>>> sh.get_token()
'sh'
>>> sh.get_token()
')'
>>> sh.get_token()
etc...
Python 2.2 and maybe lower:
>>> import shlex
>>> import StringIO
>>> s = StringIO.StringIO('$(which sh)')
>>> sh = shlex.shlex(s)
>>> sh.get_token()
'$'
>>> sh.get_token()
'('
>>> sh.get_token()
'which'
>>> sh.get_token()
'sh'
>>> sh.get_token()
')'
>>> sh.get_token()
etc...
Hth,
M.E.Farmer
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Re: Exception question
Ron Adam wrote: > > Do exceptions that take place get stored in a stack or list someplace? [snip] > I know I can catch the error and store it myself with, > > except Exception, exc: > > or possibly, > > errlist = [] > errlist.append(sys.exc_info()) > > But what I want to know is does the interpreter do that in any way? And > if so, can I access it? No, but there's been some recent talk about having it do so: http://mail.python.org/pipermail/python-dev/2005-May/053672.html If that happens though, it's not likely to show up before Python 3.0. Too backwards incompatible to do now. It also seems that the exact semantics haven't yet been agreed upon. STeVe -- http://mail.python.org/mailman/listinfo/python-list
stop
Enough salvation for one day. -- http://mail.python.org/mailman/listinfo/python-list
Massenhafter Steuerbetrug durch auslaendische Arbeitnehmer
Lese selbst: http://www.rp-online.de/public/article/nachrichten/wirtschaft/finanzen/deutschland/85815 -- http://mail.python.org/mailman/listinfo/python-list
Transparenz ist das Mindeste
Lese selbst: http://www.npd.de/npd_info/deutschland/2005/d0405-39.html -- http://mail.python.org/mailman/listinfo/python-list
Re: Jesus said, "I am the way, the truth and the life: no one can come to the Father(God)(in Heaven), but by me." (John 14:6) This means that if you die without trusting in Jesus Christ as your Lord and Saviour you will die in your sins and be forever sepa
I'm so glad you've decided what everyone believes "don freeman" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > > > > http://www.gotquestions.org/sinners-prayer.html << I saw this site on a > > search directory. Great Resource! > > > > > C'mon, this is the 21st century. Nobody believes that silly story about > God having a son anymore. > > Think about it. The original story is always the best. The sequel is > always a commercial rip-off. Frankenstein was literature. Son of > Frankenstein was silly. > > God impregnates a virgin woman and gives birth to a half man/half god, > who can walk on water and turn water into wine, but who can't defend > himself very well at all from the Romans. This story may have sold in > the past, but not now. We've become too sophisticated for this kind of > fantasy. > -- http://mail.python.org/mailman/listinfo/python-list
Re: converting a set into a sorted list
Robert Kern wrote: > MackS wrote: > >> Dear all, >> >> I've got several large sets in my program. After performing several >> operations on these I wish to present one set to the user [as a list] >> sorted according to a certain criterion. Is there any direct way to do >> so? Or must I >> >> list = [] >> >> for item in set1: >>list.append(item) >> >> list.sort() So, for this example, just do: sorted(set1) -- Brian Beck Adventurer of the First Order -- http://mail.python.org/mailman/listinfo/python-list
Re: converting a set into a sorted list
"MackS" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > Can I somehow avoid doing this in two stages? Can I somehow avoid first > creating a long list only to immediately sort it afterwards? Yes, you could interatively extract and append the min of the set (selection sort), but this would be O(n**2), like bubble or insert sort, instead of the O(n*logn) of make list and sort. You can do the latter in two statements without append: display = list(big_set) display.sort(). As Robert noted, this can be condensed to one using sorted, but that will do the same as the two lines above. Terry J. Reedy -- http://mail.python.org/mailman/listinfo/python-list
Exception question
I'm trying to understand exception handling better and have a question I haven't been able to find an answer too. Which probably means It won't work, but... Do exceptions that take place get stored in a stack or list someplace? For example in: try: try: try: riskyfunc() # error 1 except: pass crazyclass() # error 2 except: pass iffycalc() # error 3 except: pass # print any errors that occurred here. If errors 1,2,and 3 are possible errors, can I get a list of them, or can I only see the last one? I know I can catch the error and store it myself with, except Exception, exc: or possibly, errlist = [] errlist.append(sys.exc_info()) But what I want to know is does the interpreter do that in any way? And if so, can I access it? Cheers, _Ron_Adam -- http://mail.python.org/mailman/listinfo/python-list
Please confirm (conf#8d26af0fb789e6023d272db682e0f9b4)
Thank you for your feedback. Due to high levels of spam and virus activity on this mailing list the message you sent (attached below) requires confirmation before it can be delivered. To confirm that you sent the message below, simply reply to this message, leaving the Subject line unchanged (you don't need to edit anything). Once this is done your original message will be delivered and no more confirmations will be necessary. We apologize for the inconvenience and thank you for your patience, The Message Queue Team This email account is protected by: Active Spam Killer (ASK) V2.4.1 - (C) 2001-2002 by Marco Paganini For more information visit http://www.paganini.net/ask --- Original Message Follows --- From: python-list@python.org To: [EMAIL PROTECTED] Date: Sun, 15 May 2005 02:58:54 UTC Subject: Dresden Bombing Is To Be Regretted Enormously Full Article: http://service.spiegel.de/cache/international/0,1518,341239,00.html -- http://mail.python.org/mailman/listinfo/python-list
Re: converting a set into a sorted list
MackS wrote: > Dear all, > > I've got several large sets in my program. After performing several > operations on these I wish to present one set to the user [as a list] > sorted according to a certain criterion. Is there any direct way to do > so? Or must I > > list = [] > > for item in set1: >list.append(item) > > list.sort() > > Can I somehow avoid doing this in two stages? Can I somehow avoid first > creating a long list only to immediately sort it afterwards? In Python 2.4, In [1]:sorted? Type: builtin_function_or_method Base Class: String Form: Namespace: Python builtin Docstring: sorted(iterable, cmp=None, key=None, reverse=False) --> new sorted list -- Robert Kern [EMAIL PROTECTED] "In the fields of hell where the grass grows high Are the graves of dreams allowed to die." -- Richard Harter -- http://mail.python.org/mailman/listinfo/python-list
Re: Modifying a built-in function for logging purposes
[EMAIL PROTECTED] wrote: > Hi Greg, > thank for your replay, but I didn't succeed in any way. You must > consider however that I'm not a Python "expert"... > IMHO, it must be a script that change part of the interpreter, and > substitute a new module (py) in the place of the standard one (py or > pyc). The standard module must be saved in order to be able to undo the > changes and go back to the normal behaviour. > The problem is that I don't know if the built-in functions like open > (or file) are written in Python or in C and, besides that, if they can > be modified. Short answer: if you don't know stuff like this, then you probably shouldn't mess around with the builtins in production code. Depending on your operating system, there are probably programs that let you list all of the files that have been opened on your system. For example, on OS X, lsof(1) does the trick. > Other solutions which modify the source to be logged, are not > solutions, because it is far simpler to introduce here and there print > statements... -- Robert Kern [EMAIL PROTECTED] "In the fields of hell where the grass grows high Are the graves of dreams allowed to die." -- Richard Harter -- http://mail.python.org/mailman/listinfo/python-list
Paranoider Deutschenmoerder kommt in Psychiatrie
Lese selbst: http://brandenburg.rz.fhtw-berlin.de/poetschke.html -- http://mail.python.org/mailman/listinfo/python-list
converting a set into a sorted list
Dear all, I've got several large sets in my program. After performing several operations on these I wish to present one set to the user [as a list] sorted according to a certain criterion. Is there any direct way to do so? Or must I list = [] for item in set1: list.append(item) list.sort() Can I somehow avoid doing this in two stages? Can I somehow avoid first creating a long list only to immediately sort it afterwards? Thanks for any guidance, Mack -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
"M.E.Farmer" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > But if the parens are just fluff then get rid of them, it is clearer * > at least to me * ;) While I find unnecessary parens on the right of '=' tolerable, I agree as to the style preference. Terry J. Reedy -- http://mail.python.org/mailman/listinfo/python-list
Re: Multiple "cmp"s chained one after another
Volker Grabsch wrote: > Peter Hansen wrote: > >>Or just use the .timetuple() method on datetime objects and sort on the >>8th element of the 9-element tuple, which is the day-of-the-year. > > An interesting idea. But wouldn't sorting by (dd.month,dd.day) be more > effective? Depending on the meaning of "effective", I suppose so. > In other words: Does .timetuple() create a tuple, or does it just return > a tuple which is present anyway? I don't know what it does. Normally one shouldn't care about that kind of thing. In this case, you seem to be assuming that .month and .day are values that are "present anyway", but we don't really know that either, since they could just as well be properties. If someone who knows or someone who checks the source (for a given implementation of course... it could change) cares to share, we'd know more. What good that would do us is still a mystery to me. ;-) -Peter -- http://mail.python.org/mailman/listinfo/python-list
space saving retitle of thread
aa. -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
Ok I give up you have convinced me. Of what I am not sure ;) Anyway I have always viewed : a,b,c= (1,2,3) as unpacking a tuple and : (a,b,c) = (1,2,3) as creation of a tuple It was a false assumption, I have used Python for years and have never written an unpacking as: (a,b,c) = (1,2,3) I have always put parens around my tuples I always thought that a tuple was a parens with at least one comma ;) It is just not something I have done, it seems counter to my thinking , till I read from Bengt it is the commas that make the tuple not the parens. It all makes sense now, but if they are not needed I think they that should be avoided for clarity. Steve thanks for your time. I always learn a little from you ;) M.E.Farmer -- http://mail.python.org/mailman/listinfo/python-list
Re: Jesus said, "I am the way, the truth and the life: no one can come to the Father(God)(in Heaven), but by me." (John 14:6) This means that if you die without trusting in Jesus Christ as your Lord and Saviour you will die in your sins and be forever separated from the love of God in a place called Hell. The Holy Bible descibes Hell as a place of eternal torment, suffering, pain and agony for all those who have rejected Jesus Christ. The good news is that you can be sure you are going to Heaven when this life is over if you allow Jesus Christ to save you today. Do not wait until later to be saved because you do not know exactly when you will die. [ Posted by: RonaldGrossi3848@yahoo.com on May 14, 2005 ] [ 2:52:09 pm ]
> http://www.gotquestions.org/sinners-prayer.html << I saw this site on a > search directory. Great Resource! > C'mon, this is the 21st century. Nobody believes that silly story about God having a son anymore. Think about it. The original story is always the best. The sequel is always a commercial rip-off. Frankenstein was literature. Son of Frankenstein was silly. God impregnates a virgin woman and gives birth to a half man/half god, who can walk on water and turn water into wine, but who can't defend himself very well at all from the Romans. This story may have sold in the past, but not now. We've become too sophisticated for this kind of fantasy. -- http://mail.python.org/mailman/listinfo/python-list
Re: Multiple "cmp"s chained one after another
vincent wehren wrote:
>
>| > If you don't care about the year, why not just "normalize" the year
>| > to all be the same using the replace method of the date instance?
>|
>| That's a very bad idea. In my example, this would work, but in "reality"
>| I don't sort datetime objects, of course! (Is there any real application
>| where you want to do that?)
>|
>| Instead, I'm sorting "Person" objects using a "birthday" attribute.
>| Since I use these Person objects also in other places, they should never
>| be modified without just to be sorted. In general, the number side effects
>| should always be minimized.
>
> Can you explain where you see a modification to the orginal object
> happening?
> (or in any of the other solutions proposed for that matter...)
Sorry, my fault. I didn't read carefully enough. X-)
> Not here I hope:
>
>| > datesNorm = [obj.replace(year=1900) for obj in (dates)]
>| > datesNorm.sort()
While you don't change the original objects, there's still a problem since
you're sorting the normalized values. However, I want to sort the original
list (i.e. the list of "Person" objects).
But that's not a real problem if one normalizes in a key function:
def key_birthday(d):
return d.replace(year=1900)
...
dates.sort(key=key_birthday)
..as suggested in other followups of my posting.
>| Nevertheless, I think you idea is very interesting. Is there any "real"
>| application where normalizing just for sorting would be reasonable?
>
> How about a case-insensitive sort of strings? (uppering being the
> normalization step)
> Or getting rid of accented / special characters before sorting.
> These sound like fairly straight-forward use cases to me ;)
For your solution these are good examples. But my question was, whether
normalizing first, and just sorting the normalized values (not the original
values) is reasonable.
I.e., when I sort some strings case-insensitive, I don't want my resulting
(sorted) list to contain only lowercase string. But that's what I would
get if I used the algorithm you described above.
Greets,
--
Volker Grabsch
---<<(())>>---
\frac{\left|\vartheta_0\times\{\ell,\kappa\in\Re\}\right|}{\sqrt
[G]{-\Gamma(\alpha)\cdot\mathcal{B}^{\left[\oint\!c_\hbar\right]}}}
--
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Re: A new to Python question
I explained what i meant in previous post there was nothing more than just a discussion I have no real problem here just more of a sore point in style for me. I feel that parens are quite overloaded and it can be confusing to newbies. But if the parens are just fluff then get rid of them, it is clearer * at least to me * ;) There are enough things wrapped in parens nowadays it is starting to look like lisp. > BTW, UIAM it is the commas that define tuples, so the outermost parens are really >expression >parens more than tuple syntax. Hadn't really thought of that way but it makes sense >>> w = 1,2,3 >>> w.__doc__ """tuple() -> an empty tuple tuple(sequence) -> tuple initialized from sequence's items If the argument is a tuple, the return value is the same object.""" Thanks for your time Bengt! M.E.Farmer -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
M.E.Farmer wrote: >>They're both an UNPACK_SEQUENCE byte-code. > > I have dissed it myself ;) > My argument, if you can call it that, is that it is not clear that > Python is going to do a tuple unpacking here or not ! Hmm... Well, I wouldn't say that. I think it's quite clear that Python's doing a tuple unpacking. Just like it always does anytime there's a comma on the left-hand side of an assignment statement. Note that there's nothing that forces you to write the unpack sequence like a tuple display. You can write it like a list display too, and Python will treat it identically: py> def unpack_tuple(t): ... [x, y] = t ... py> dis.dis(unpack_tuple) 2 0 LOAD_FAST0 (t) 3 UNPACK_SEQUENCE 2 6 STORE_FAST 2 (x) 9 STORE_FAST 1 (y) 12 LOAD_CONST 0 (None) 15 RETURN_VALUE I don't know how UNPACK_SEQUENCE is implemented, but at least on the Python level, no tuple or list is created in the unpacking process. > Seems weird, non-intuitive that a tuple unpacking and tuple creation > have the same bytecode. Sorry, I don't understand. Why do you think this? py> def create_tuple(x, y): ... (x, y) ... py> dis.dis(create_tuple) 2 0 LOAD_FAST0 (x) 3 LOAD_FAST1 (y) 6 BUILD_TUPLE 2 9 POP_TOP 10 LOAD_CONST 0 (None) 13 RETURN_VALUE py> def unpack_tuple(t): ... x, y = t ... py> dis.dis(unpack_tuple) 2 0 LOAD_FAST0 (t) 3 UNPACK_SEQUENCE 2 6 STORE_FAST 2 (x) 9 STORE_FAST 1 (y) 12 LOAD_CONST 0 (None) 15 RETURN_VALUE To me, it looks like tuple creation uses the BUILD_TUPLE op-code, and tuple unpacking uses the UNPACK_SEQUENCE op-code. Could you explain what you meant by "a tuple unpacking and tuple creation have the same bytecode"? STeVe -- http://mail.python.org/mailman/listinfo/python-list
Re: Modifying a built-in function for logging purposes
Hi Greg, thank for your replay, but I didn't succeed in any way. You must consider however that I'm not a Python "expert"... IMHO, it must be a script that change part of the interpreter, and substitute a new module (py) in the place of the standard one (py or pyc). The standard module must be saved in order to be able to undo the changes and go back to the normal behaviour. The problem is that I don't know if the built-in functions like open (or file) are written in Python or in C and, besides that, if they can be modified. Other solutions which modify the source to be logged, are not solutions, because it is far simpler to introduce here and there print statements... Bye. -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
>It actually is the same, and I don't think implicit or explicit is the
>difference you should be citing here.
Why not it is relevant and true that Python is doing an implicit
unpacking of the values in that unnamed tuple.
Quoting myself """It might be the "same" as
no parens but it isn't very clear. If you want a tuple make it
explicit, if you want individual names make it explicit."""
So as you say, maybe it is is fully a matter of style and apparently I
don't like that style!
>They're both an UNPACK_SEQUENCE byte-code.
I have dissed it myself ;)
My argument, if you can call it that, is that it is not clear that
Python is going to do a tuple unpacking here or not !
You had to dis it to find out and you are not a newbie.
# extra fluff from pyshell
>>> import dis
>>> dis.dis(compile('(x,y,dotp,sumx,maxv) =
abc(x,y,dotp,sumx,maxv)','','exec'))
0 SET_LINENO 0
3 SET_LINENO 1
6 LOAD_NAME0 (abc)
9 LOAD_NAME1 (x)
12 LOAD_NAME2 (y)
15 LOAD_NAME3 (dotp)
18 LOAD_NAME4 (sumx)
21 LOAD_NAME5 (maxv)
24 CALL_FUNCTION5
27 UNPACK_SEQUENCE 5
30 STORE_NAME 1 (x)
33 STORE_NAME 2 (y)
36 STORE_NAME 3 (dotp)
39 STORE_NAME 4 (sumx)
42 STORE_NAME 5 (maxv)
45 LOAD_CONST 0 (None)
48 RETURN_VALUE
>>> dis.dis(compile('x,y,dotp,sumx,maxv =
abc(x,y,dotp,sumx,maxv)','','exec'))
0 SET_LINENO 0
3 SET_LINENO 1
6 LOAD_NAME0 (abc)
9 LOAD_NAME1 (x)
12 LOAD_NAME2 (y)
15 LOAD_NAME3 (dotp)
18 LOAD_NAME4 (sumx)
21 LOAD_NAME5 (maxv)
24 CALL_FUNCTION5
27 UNPACK_SEQUENCE 5
30 STORE_NAME 1 (x)
33 STORE_NAME 2 (y)
36 STORE_NAME 3 (dotp)
39 STORE_NAME 4 (sumx)
42 STORE_NAME 5 (maxv)
45 LOAD_CONST 0 (None)
48 RETURN_VALUE
>>> dis.dis(compile('tup = abc(x,y,dotp,sumx,maxv)','','exec'))
0 SET_LINENO 0
3 SET_LINENO 1
6 LOAD_NAME0 (abc)
9 LOAD_NAME1 (x)
12 LOAD_NAME2 (y)
15 LOAD_NAME3 (dotp)
18 LOAD_NAME4 (sumx)
21 LOAD_NAME5 (maxv)
24 CALL_FUNCTION5
27 STORE_NAME 6 (tup)
30 LOAD_CONST 0 (None)
33 RETURN_VALUE
>>>
You may notice that the act of assigning the return values to a unnamed
tuple and a name have different semantics and that was the real point.
The problem is why should this be the same:
a,b,c=(1,2,3)
(a,b,c)=(1,2,3)
Seems weird, non-intuitive that a tuple unpacking and tuple creation
have the same bytecode.
So why is this done? What is the reason, I am sure there are a few ;)
p.s. I am leaving out for a while and will read/followup later if
needed. Thank you all for your time.
M.E.Farmer
--
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Re: A new to Python question
On 14 May 2005 13:25:55 -0700, "M.E.Farmer" <[EMAIL PROTECTED]> wrote:
>I said exactly what I meant, the parentheses around the values creates
>a tuple that you have no reference to! It also has a side effect of
I don't understand what you are saying, or meaning ;-)
BTW, the function call has nothing to do with what happens on the left hand side
of the assignment. It is only the result of the function call that counts, so we
could as well use a literal or other expression. This is a matter of unpacking
a sequence according to the left hand target. E.g.,
>>> iter([1,2,3])
>>> a,b,c = iter([1,2,3])
>>> d,e,f = [1,2,3]
>>> g,h,i = 'GHI'
>>> [a,b,c,d,e,f,g,h,i]
[1, 2, 3, 1, 2, 3, 'G', 'H', 'I']
Ok, now looking at the code for the assignment to a,b,c vs to (a,b,c):
>>> import dis
>>> dis.dis(compile('(a,b,c) = iter([1,2,3])','','exec'))
1 0 LOAD_NAME0 (iter)
3 LOAD_CONST 0 (1)
6 LOAD_CONST 1 (2)
9 LOAD_CONST 2 (3)
12 BUILD_LIST 3
15 CALL_FUNCTION1
18 UNPACK_SEQUENCE 3
21 STORE_NAME 1 (a)
24 STORE_NAME 2 (b)
27 STORE_NAME 3 (c)
30 LOAD_CONST 3 (None)
33 RETURN_VALUE
>>> dis.dis(compile('a,b,c = iter([1,2,3])','','exec'))
1 0 LOAD_NAME0 (iter)
3 LOAD_CONST 0 (1)
6 LOAD_CONST 1 (2)
9 LOAD_CONST 2 (3)
12 BUILD_LIST 3
15 CALL_FUNCTION1
18 UNPACK_SEQUENCE 3
21 STORE_NAME 1 (a)
24 STORE_NAME 2 (b)
27 STORE_NAME 3 (c)
30 LOAD_CONST 3 (None)
33 RETURN_VALUE
I don't see anything in the code about creating a tuple that you have no
reference to.
To see the unpacking of "GHI" so as to get rid of the function call red herring:
>>> dis.dis(compile('a,b,c = "GHI"','','exec'))
1 0 LOAD_CONST 0 ('GHI')
3 UNPACK_SEQUENCE 3
6 STORE_NAME 0 (a)
9 STORE_NAME 1 (b)
12 STORE_NAME 2 (c)
15 LOAD_CONST 1 (None)
18 RETURN_VALUE
>>> dis.dis(compile('(a,b,c) = "GHI"','','exec'))
1 0 LOAD_CONST 0 ('GHI')
3 UNPACK_SEQUENCE 3
6 STORE_NAME 0 (a)
9 STORE_NAME 1 (b)
12 STORE_NAME 2 (c)
15 LOAD_CONST 1 (None)
18 RETURN_VALUE
ISTM the assignment part starts with UNPACK_SEQUENCE and all the code looks the
same.
BTW, UIAM it is the commas that define tuples, so the outermost parens are
really expression
parens more than tuple syntax. But note that you can have nested tuple
structure as target,
and that does change the unpacking code (and what it expects to have available
to unpack):
>>> (x,(y,z)) = 'XYZ'
Traceback (most recent call last):
File "", line 1, in ?
ValueError: too many values to unpack
>>> (x,(y,z)) = 'X','YZ'
>>> x
'X'
>>> y
'Y'
>>> z
'Z'
>>> (x,(y,z)) = [1, [2,3]]
>>> x
1
>>> y
2
>>> z
3
>>> dis.dis(compile('(x,(y,z)) = 0','','exec'))
1 0 LOAD_CONST 0 (0)
3 UNPACK_SEQUENCE 2
6 STORE_NAME 0 (x)
9 UNPACK_SEQUENCE 2
12 STORE_NAME 1 (y)
15 STORE_NAME 2 (z)
18 LOAD_CONST 1 (None)
21 RETURN_VALUE
Obviously we can't unpack the zero, but the code doesn't know
that until it tries it, so we can look at what the left hand side code is
independent of the right hand side.
>binding the names inside the tuple to a value and placing them in the
>local namespace( implicit tuple unpacking ). It might be the "same" as
>no parens but it isn't very clear. If you want a tuple make it
>explicit, if you want individual names make it explicit.
OTOH, you might want a mix:
>>> a, tup, (b,c), d = ['A', ('a', 'tuple'), 'BC', 'Sandra']
>>> a
'A'
>>> tup
('a', 'tuple')
>>> b
'B'
>>> c
'C'
>>> d
'Sandra'
Or with gratuitous _outer_ parens:
>>> (a, tup, (b,c), d) = ['A', ('a', 'tuple'), 'BC', 'Sandra']
>>> a
'A'
>>> tup
('a', 'tuple')
>>> b
'B'
>>> c
'C'
>>> d
'Sandra'
>>> dis.dis(compile("a, tup, (b,c), d = ['A', ('a', 'tuple'), 'BC',
>>> 'Sandra']",'','exec'))
1 0 LOAD_CONST 0 ('A')
3 LOAD_CONST 6 (('a', 'tuple'))
6 LOAD_CONST 3 ('B
Re: A new to Python question
On 14 May 2005 10:44:30 -0700, "M.E.Farmer" <[EMAIL PROTECTED]> wrote: [...] >Be sure to study up on namespaces, it will ease your Python woes. >Namespaces are the most fundamental part of Python that new users don't >understand. Namespace mastery will take you far. >Just remember there are only two scopes local and global ;) And don't jump to conclusions when you read a line like the last above ;-) I.e., there can be many different local and global scopes, not just one of each, and since Python is a very dynamic language, existence of things can vary with execution time and logic, so those scopes don't all have to exist at the same time, or at all, nor persist until the program runs to its end. Also, ISTM "local" is probably being stretched a little above to include nested scopes, which are a bit different from either plain local or global in how you can access them. I would second the advice to explore namespaces, and particularly attribute name spaces such as are defined by classes. Attribute access and descriptors conspire to enable much of the magic you can cook up with Python, as well as stuff that happens automatically. In short, a whole unopened deluxe set of programming Legos is at your elbow, besides the pieces you have encountered so far. Have fun ;-) Regards, Bengt Richter -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
Steven Bethard wrote: > > I don't know the implementation enough to know whether or not a tuple is > actually created when "b" and "c" are bound to their values, but I'd be > willing to bet that whatever happens to "(b, c)" is exactly the same as > what happens to "b, c". Some corroborating evidence: py> def f(t): ... (b, c) = t ... py> def g(t): ... b, c = t ... py> import dis py> dis.dis(f) 2 0 LOAD_FAST0 (t) 3 UNPACK_SEQUENCE 2 6 STORE_FAST 2 (b) 9 STORE_FAST 1 (c) 12 LOAD_CONST 0 (None) 15 RETURN_VALUE py> dis.dis(g) 2 0 LOAD_FAST0 (t) 3 UNPACK_SEQUENCE 2 6 STORE_FAST 2 (b) 9 STORE_FAST 1 (c) 12 LOAD_CONST 0 (None) 15 RETURN_VALUE They're both an UNPACK_SEQUENCE byte-code. STeVe -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
M.E.Farmer wrote: > I said exactly what I meant, the parentheses around the values creates > a tuple that you have no reference to! It also has a side effect of > binding the names inside the tuple to a value and placing them in the > local namespace( implicit tuple unpacking ). It might be the "same" as > no parens but it isn't very clear. If you want a tuple make it > explicit, if you want individual names make it explicit. It actually is the same, and I don't think implicit or explicit is the difference you should be citing here. The parentheses are fully optional -- they don't change the semantics at all: py> t = (4, 5) py> a = t py> a is t True py> a = (b, c) = t py> a is t True py> a = b, c = t py> a is t True In all cases, "a" still gets assigned the tuple (4, 5). Whether or not you put the parentheses around "b, c" is fully a matter of style. I don't know the implementation enough to know whether or not a tuple is actually created when "b" and "c" are bound to their values, but I'd be willing to bet that whatever happens to "(b, c)" is exactly the same as what happens to "b, c". STeVe -- http://mail.python.org/mailman/listinfo/python-list
Re: tkinter puzzler
Martin Franklin <[EMAIL PROTECTED]> writes: > I suspect you need to look at the columnconfigure / rowconfigure methods > of the container (toplevel or frame) Thanks, columnconfigure turned out to be the answer and Peter Otten's post showing how to use it was very informative. For some reason columnconfigure is not documented in the otherwise excellent tkinter reference manual from New Mexico Tech. I'm having sort of a different prob now, which is I want to make a pulldown menu as commonly seen on web pages. The NMT reference suggests using the MenuButton widget, which sort of works, though the entrycget and entryconfigure methods that are supposedly on the menu items aren't really there. The toolkit itself says that MenuButton is now considered obsolete and Frederik Lundh's manual seems to say to use Menu somehow instead, but I haven't quite figured out how. Is there a preferred and normal way to do this? One thing I need is to be able to disable individual menu choices based on stuff happening in the application, which is why I wanted to use entryconfigure. Also, I don't see how to get the little horizontal bar marker on the button (as seen in IDLE) indicating that the button is a pulldown. A minute examining the IDLE source code didn't show it either, though I can probably find it there with more effort. Thanks as usual. -- http://mail.python.org/mailman/listinfo/python-list
incorrect(?) shlex behaviour
Consider:
>>> import shlex
>>> shlex.split('$(which sh)')
['$(which', 'sh)']
Is this behavior correct? It seems that I should
either get one token, or the list
['$','(','which','sh',')'],
but certainly breaking it the way it does is
erroneous.
Can anyone explain why the string is being split
that way?
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Re: Modifying a built-in function for logging purposes
[EMAIL PROTECTED] wrote: > Hi all, > I wonder if it is possible to change (temporarily) a built-in function > for logging purposes. > Let me explain: > I want to log all the 'open' operations, recording the file to be > opened, the "mode" (r/w/a...) and (possibly) the module which made the > call. > After that the 'open' can carry on following the standard built-in > path. > Possibly I don't want to have to modify the source of the application > to be logged. > If there is another solution, I am open to any suggestion... > > Bye. > Would this work? _file = file def file(path, mode): print path, mode return _file(path, mode) -greg -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
I said exactly what I meant, the parantheses around the values creates a tuple that you have no reference to! It also has a side effect of binding the names inside the tuple to a value and placing them in the local namespace. It might be the "same" but it isn't very clear. If you want a tuple make it explicit, if you want individual names make it explicit. >>> def f(q,w,e,r): ... return q,w,e,r ... >>> # diff names >>> a,b,c,d= f(1,2,3,4)# explicit tuple unpacking >>> dir() ['__builtins__', '__doc__', '__name__', 'a', 'b', 'c', 'd', 'f', 'shell'] >>> del a,b,c,d >>> # where is the tuple >>> (a,b,c,d)= f(1,2,3,4)# implicit tuple unpacking !? >>> dir() ['__builtins__', '__doc__', '__name__', 'a', 'b', 'c', 'd', 'f', 'shell'] >>> del a,b,c,d >>> # Where is the tuple (a,b,c,d)? There isn't one. >>> # assign to a single name ( don't do tuple unpacking ) >>> tup=f(1,2,3,4) >>> dir() ['__builtins__', '__doc__', '__name__', 'f', 'shell', 'tup'] Now there is. Steve since you are closer to expert than novice you understand the difference. I feel this can be confusing to newbies, maybe you disagree. M.E.Farmer -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
I said exactly what I meant, the parentheses around the values creates a tuple that you have no reference to! It also has a side effect of binding the names inside the tuple to a value and placing them in the local namespace( implicit tuple unpacking ). It might be the "same" as no parens but it isn't very clear. If you want a tuple make it explicit, if you want individual names make it explicit. >>> def f(q,w,e,r): ... return q,w,e,r ... >>> # diff names >>> a,b,c,d= f(1,2,3,4)# explicit tuple unpacking >>> dir() ['__builtins__', '__doc__', '__name__', 'a', 'b', 'c', 'd', 'f', 'shell'] >>> del a,b,c,d >>> # where is the tuple >>> (a,b,c,d)= f(1,2,3,4)# implicit tuple unpacking !? >>> dir() ['__builtins__', '__doc__', '__name__', 'a', 'b', 'c', 'd', 'f', 'shell'] >>> del a,b,c,d >>> # Where is the tuple (a,s,d,f)? There isn't one. >>> # assign to a single name ( don't do tuple unpacking ) >>> tup=f(1,2,3,4) >>> dir() ['__builtins__', '__doc__', '__name__', 'f', 'shell', 'tup'] Now there is. Steve since you are closer to expert than novice you understand the difference. I feel this can be confusing to newbies, maybe you disagree. M.E.Farmer -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
On Sat, 14 May 2005 20:38:26 +0200, Bernd Nawothnig <[EMAIL PROTECTED]> wrote:
>
>> On 2005-05-14, M.E.Farmer wrote:
>
>> (x,y,dotp,sumx,maxv) = abc(x,y,dotp,sumx,maxv)
>> This will only create a tuple in memory that has no name to reference
>> it by!
>
>Maybe. But it does not seem to hurt. And I am not sure the tupel _is_
>really created in that situation.
>
One way to get insight into what a statement does is to disassemble its code,
e.g.,
>>> import dis
>>> dis.dis(compile('(x,y,dotp,sumx,maxv) =
>>> abc(x,y,dotp,sumx,maxv)','','exec'))
1 0 LOAD_NAME0 (abc)
3 LOAD_NAME1 (x)
6 LOAD_NAME2 (y)
9 LOAD_NAME3 (dotp)
12 LOAD_NAME4 (sumx)
15 LOAD_NAME5 (maxv)
18 CALL_FUNCTION5
21 UNPACK_SEQUENCE 5
24 STORE_NAME 1 (x)
27 STORE_NAME 2 (y)
30 STORE_NAME 3 (dotp)
33 STORE_NAME 4 (sumx)
36 STORE_NAME 5 (maxv)
39 LOAD_CONST 0 (None)
42 RETURN_VALUE
In the context of a function or module scope, those loads and stores will change
to optimized byte code ops like LOAD_FAST and STORE_FAST etc, but you can see
what's
happening above. I.e., on return from the function call, the returned sequence
(we know it's
a tuple in your example, but it could be some other sequence thing) is upacked
and its elements
are bound to the individual names, just as individual "assignments" would do.
Regards,
Bengt Richter
--
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Re: Multiple "cmp"s chained one after another
"Volker Grabsch" <[EMAIL PROTECTED]> schrieb im
Newsbeitrag news:[EMAIL PROTECTED]
| vincent wehren wrote:
| >
| > If you don't care about the year, why not just "normalize" the year
| > to all be the same using the replace method of the date instance?
|
| That's a very bad idea. In my example, this would work, but in "reality"
| I don't sort datetime objects, of course! (Is there any real application
| where you want to do that?)
|
| Instead, I'm sorting "Person" objects using a "birthday" attribute.
| Since I use these Person objects also in other places, they should never
| be modified without just to be sorted. In general, the number side effects
| should always be minimized.
Can you explain where you see a modification to the orginal object
happening?
(or in any of the other solutions proposed for that matter...)
Not here I hope:
|
| > datesNorm = [obj.replace(year=1900) for obj in (dates)]
| > datesNorm.sort()
If you print datesNorm, you'll see:
[datetime.date(1900, 12, 2), datetime.date(1900, 12, 3), datetime.date(1900,
12, 6), datetime.date(1900, 12, 7)]
However, dates is still the same:
[datetime.date(2004, 12, 2), datetime.date(2001, 12, 3), datetime.date(2002,
12, 6), datetime.date(1977, 12, 7)]
|
| This code would go bad especially in my situation, where my "Person"
| objects are SQLObjects, thus the "normalisation" would be written into
| the database. Okay, one could use transactions and rollback", but I
| think, my point is clear now.
Since you wouldn't need to change the attribute object to
perform a sort (on the instances) using it (or portions of it) as key, it's
not.
Or is there something fundamental I am missing about your particular use
case?
| Nevertheless, I think you idea is very interesting. Is there any "real"
| application where normalizing just for sorting would be reasonable?
How about a case-insensitive sort of strings? (uppering being the
normalization step)
Or getting rid of accented / special characters before sorting.
These sound like fairly straight-forward use cases to me ;)
Anyway, I was doing some SQL this morning where getting rid of portions of
'datetime' fields in
a WHERE clause is sometimes just the ticket - hence the connection.
--
Vincent
|
| --
| Volker Grabsch
| ---<<(())>>---
| \frac{\left|\vartheta_0\times\{\ell,\kappa\in\Re\}\right|}{\sqrt
| [G]{-\Gamma(\alpha)\cdot\mathcal{B}^{\left[\oint\!c_\hbar\right]}}}
--
http://mail.python.org/mailman/listinfo/python-list
Re: Faster GUI text control
That's a good point about the amount of text available at once. As long as I could swap the visible section fast enough that might be a good solution. This will run mostly on Windows, but I'd like for it to be equally usable on Linux. -- http://mail.python.org/mailman/listinfo/python-list
Re: Faster GUI text control
> > no, it would mean writing some python code. if all you need is a scrolling > text list, you can simply use the code on this page: > > http://effbot.org/zone/wck-4.htm > > (see "A scrollable list view, with scrollbar support" and, optionally, > the virtual data modifications under "Displaying Huge Data Sets") > > the resulting widget will update at constant speed, independent of the > data size. > > > Thanks for the suggestion. I looked at that, but I need to be able to selectively change colors on parts of the text and I didn't think I could do that with a list box. Am I misunderstanding that? -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
David wrote: > Thank you very much. Tulpes are really neat now that I've looked at > them. So after just fixing it, I changed it up and I would like to > show it off now. > > #! /usr/bin/python > #This program takes two vectors and multiplies them > #against a 10X10 array. It also then gives the dot product, > #sum, and max value of the array. > > import Numeric > def abc(package): > """Takes two arrays and performs predetermined calculations, >Then returns the solutions back as the same array, along >with the dot product, sum, and max value of the array. > >Data slots: >0 - First Array >1 - Second Array >2 - Dot product >3 - Sum >4 - Max Value""" > f = Numeric.zeros((10,10)) > for i in range(10): > for j in range(10): > f[i,j] = (i+1)+(j+1) > > e = Numeric.matrixmultiply(f, package[0]) > g = Numeric.matrixmultiply(Numeric.transpose(f),package[1]) > package[0] = e > package[1] = g > package[2] = Numeric.dot(package[0],package[1]) > package[3] = Numeric.sum(package[0]) > package[4] = package[1][Numeric.argmax(package[1])] > return package > > data = [Numeric.arange(1,11),Numeric.arange(1,11)*2,0,0,0] > #data = [Array X, Array Y, Dot product, Sum, Max Value] > > print 'Array X:',data[0] > print 'Array Y:',data[1] > > data = abc(data) > > print 'Calling function abc' > print 'Array X:',data[0] > print 'Array Y:',data[1] > print 'Dot Product of X and Y:',data[2] > print 'Sum of array X:',data[3] > print 'Max value of array Y:',data[4] > > I think its just wonderful now, but if you got any other suggestions, > Please do tell. Thanks everyone. It's still not very Pythonic. Don't bother putting outputs in the argument list. There are some good use cases for doing so, but until you've been writing Python code for a while and the Pythonic idioms come naturally to you, you should probably resist the urge. Python is not Fortran. def abc(x, y): ... e = Numeric.matrixmultiply(f, x) g = Numeric.matrixmultiply(Numeric.transpose(f), y) dotp = Numeric.dot(x, y) sumx = Numeric.sum(x) maxy = Numeric.maximum.reduce(y) return e, g, dotp, sumx, maxy x = Numeric.arange(1,11) y = x*2 x, y, dotp, sumx, maxy = abc(x, y) -- Robert Kern [EMAIL PROTECTED] "In the fields of hell where the grass grows high Are the graves of dreams allowed to die." -- Richard Harter -- http://mail.python.org/mailman/listinfo/python-list
Re: Returning Date As String ?
Peter Moscatt wrote:
> I am wanting to return the system date using the following:
>
> date.today()
>
> How would I then convert this to a string ?
Use the strftime method. The formatting directives are documented here:
http://docs.python.org/lib/module-time.html
Example: date.today().strftime("%B %d, %Y")
--
Brian Beck
Adventurer of the First Order
--
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Modifying a built-in function for logging purposes
Hi all, I wonder if it is possible to change (temporarily) a built-in function for logging purposes. Let me explain: I want to log all the 'open' operations, recording the file to be opened, the "mode" (r/w/a...) and (possibly) the module which made the call. After that the 'open' can carry on following the standard built-in path. Possibly I don't want to have to modify the source of the application to be logged. If there is another solution, I am open to any suggestion... Bye. -- http://mail.python.org/mailman/listinfo/python-list
Re: Jesus said, "I am the way, the truth and the life: no one can come to the Father(God)(in Heaven), but by me." (John 14:6) This means that if you die without trusting in Jesus Christ as your Lord and Saviour you will die in your sins and be forever separated from the love of God in a place called Hell. The Holy Bible descibes Hell as a place of eternal torment, suffering, pain and agony for all those who have rejected Jesus Christ. The good news is that you can be sure you are going to Heaven when this life is over if you allow Jesus Christ to save you today. Do not wait until later to be saved because you do not know exactly when you will die. [ Posted by: RonaldGrossi3848@yahoo.com on May 14, 2005 ] [ 2:52:09 pm ]
Abuse reports to [EMAIL PROTECTED],[EMAIL PROTECTED],[EMAIL PROTECTED],[EMAIL PROTECTED],[EMAIL PROTECTED],[EMAIL PROTECTED],[EMAIL PROTECTED],[EMAIL PROTECTED] -- http://mail.python.org/mailman/listinfo/python-list
Re: Multiple "cmp"s chained one after another
Peter Hansen wrote:
>
> Or just use the .timetuple() method on datetime objects and sort on the
> 8th element of the 9-element tuple, which is the day-of-the-year.
An interesting idea. But wouldn't sorting by (dd.month,dd.day) be more
effective?
In other words: Does .timetuple() create a tuple, or does it just return
a tuple which is present anyway?
Greets,
--
Volker Grabsch
---<<(())>>---
\frac{\left|\vartheta_0\times\{\ell,\kappa\in\Re\}\right|}{\sqrt
[G]{-\Gamma(\alpha)\cdot\mathcal{B}^{\left[\oint\!c_\hbar\right]}}}
--
http://mail.python.org/mailman/listinfo/python-list
Jesus said, "I am the way, the truth and the life: no one can come to the Father(God)(in Heaven), but by me." (John 14:6) This means that if you die without trusting in Jesus Christ as your Lord and Saviour you will die in your sins and be forever separated from the love of God in a place called Hell. The Holy Bible descibes Hell as a place of eternal torment, suffering, pain and agony for all those who have rejected Jesus Christ. The good news is that you can be sure you are going to Heaven when this life is over if you allow Jesus Christ to save you today. Do not wait until later to be saved because you do not know exactly when you will die. [ Posted by: RonaldGrossi3848@yahoo.com on May 14, 2005 ] [ 2:52:09 pm ]
http://www.gotquestions.org/sinners-prayer.html << I saw this site on a search directory. Great Resource! -- http://mail.python.org/mailman/listinfo/python-list
Re: Multiple "cmp"s chained one after another
vincent wehren wrote:
>
> If you don't care about the year, why not just "normalize" the year
> to all be the same using the replace method of the date instance?
That's a very bad idea. In my example, this would work, but in "reality"
I don't sort datetime objects, of course! (Is there any real application
where you want to do that?)
Instead, I'm sorting "Person" objects using a "birthday" attribute.
Since I use these Person objects also in other places, they should never
be modified without just to be sorted. In general, the number side effects
should always be minimized.
> datesNorm = [obj.replace(year=1900) for obj in (dates)]
> datesNorm.sort()
This code would go bad especially in my situation, where my "Person"
objects are SQLObjects, thus the "normalisation" would be written into
the database. Okay, one could use transactions and rollback", but I
think, my point is clear now.
Nevertheless, I think you idea is very interesting. Is there any "real"
application where normalizing just for sorting would be reasonable?
Greets,
--
Volker Grabsch
---<<(())>>---
\frac{\left|\vartheta_0\times\{\ell,\kappa\in\Re\}\right|}{\sqrt
[G]{-\Gamma(\alpha)\cdot\mathcal{B}^{\left[\oint\!c_\hbar\right]}}}
--
http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
Yes, I gathered. We all get our habits from somewhere :-) Regards, Philippe Bernd Nawothnig wrote: > On 2005-05-14, Philippe C. Martin wrote: > >> You're thinking you're passing the arguments as reference > > That is the way Fortran handles them: > > [...] > >>> Right now I'm taking a simple program I wrote in Fortran > > > > > Bernd > -- http://mail.python.org/mailman/listinfo/python-list
Re: sockets don't play nice with new style classes :(
Paul> It seems to me that the socket module itself should be rewritten Paul> to use new style classes, so that socket.socket objects can extend Paul> _socket.socket instead of wrapping them. Paul> Am I missing something? Probably not. The socket module could use some attention. Skip -- http://mail.python.org/mailman/listinfo/python-list
Re: Multiple "cmp"s chained one after another
Steven Bethard wrote:
> Robert Kern wrote:
> def mykey(d):
> return (d.month, d.day)
>
> The point here is that rather than chaining cmp() calls with ors, you
> should just use a tuple -- the standard comparison order in tuples is
> exactly what you're looking for.
That's an excellent idea! Thanks a lot. I really didn't think of the "key="
argument.
Greets,
--
Volker Grabsch
---<<(())>>---
\frac{\left|\vartheta_0\times\{\ell,\kappa\in\Re\}\right|}{\sqrt
[G]{-\Gamma(\alpha)\cdot\mathcal{B}^{\left[\oint\!c_\hbar\right]}}}
--
http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
> On 2005-05-14, M.E.Farmer wrote: > (x,y,dotp,sumx,maxv) = abc(x,y,dotp,sumx,maxv) > This will only create a tuple in memory that has no name to reference > it by! Maybe. But it does not seem to hurt. And I am not sure the tupel _is_ really created in that situation. > How would you access the returned value? > If you want a tuple you need to assign all the return vales to a single > name. We do not want the tuple. Python 2.3.5 (#1, Apr 28 2005, 12:14:04) [GCC 3.4.3-20050110 (Gentoo Linux 3.4.3.20050110-r2, ssp-3.4.3.20050110-0, pie- on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> def foo(): >>> ... return 1,2,3 >>> ... >>> (a,b,c)=foo() >>> print a,b,c 1 2 3 >>> works. Of course, you can omit the (): >>> a,b,c=foo() >>> print a,b,c 1 2 3 That makes no difference. Bernd -- Those who desire to give up freedom in order to gain security, will not have, nor do they deserve, either one. [T. Jefferson] -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
Hmm don't know what happened. I guess the formatting got all chewed up. -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
Thank you very much. Tulpes are really neat now that I've looked at them. So after just fixing it, I changed it up and I would like to show it off now. #! /usr/bin/python #This program takes two vectors and multiplies them #against a 10X10 array. It also then gives the dot product, #sum, and max value of the array. import Numeric def abc(package): """Takes two arrays and performs predetermined calculations, Then returns the solutions back as the same array, along with the dot product, sum, and max value of the array. Data slots: 0 - First Array 1 - Second Array 2 - Dot product 3 - Sum 4 - Max Value""" f = Numeric.zeros((10,10)) for i in range(10): for j in range(10): f[i,j] = (i+1)+(j+1) e = Numeric.matrixmultiply(f, package[0]) g = Numeric.matrixmultiply(Numeric.transpose(f),package[1]) package[0] = e package[1] = g package[2] = Numeric.dot(package[0],package[1]) package[3] = Numeric.sum(package[0]) package[4] = package[1][Numeric.argmax(package[1])] return package data = [Numeric.arange(1,11),Numeric.arange(1,11)*2,0,0,0] #data = [Array X, Array Y, Dot product, Sum, Max Value] print 'Array X:',data[0] print 'Array Y:',data[1] data = abc(data) print 'Calling function abc' print 'Array X:',data[0] print 'Array Y:',data[1] print 'Dot Product of X and Y:',data[2] print 'Sum of array X:',data[3] print 'Max value of array Y:',data[4] I think its just wonderful now, but if you got any other suggestions, Please do tell. Thanks everyone. David -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
M.E.Farmer wrote: > (x,y,dotp,sumx,maxv) = abc(x,y,dotp,sumx,maxv) > This will only create a tuple in memory that has no name to reference > it by! Huh? This binds the names "x", "y", "dotp", "sumx" and "maxv" to the values returned by abc: py> def abc(*args): ... return args ... py> (x,y,dotp,sumx,maxv) = abc(2,3,5,7,11) py> x 2 py> y 3 py> dotp 5 py> sumx 7 py> maxv 11 Of course, the parentheses around x,y,dotp,sumx,maxv are unnecessary. STeVe -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
(x,y,dotp,sumx,maxv) = abc(x,y,dotp,sumx,maxv) This will only create a tuple in memory that has no name to reference it by! How would you access the returned value? If you want a tuple you need to assign all the return vales to a single name. mytup = abc(x,y,dotp,sumx,maxv) M.E.Farmer -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
David wrote:
> Hi I'm trying to teach myself python and so far to good, but I'm
having
> a bit of trouble getting a function to work the way I think it should
> work. Right now I'm taking a simple program I wrote in Fortran and
> trying to do it in Python. I got it to work, but now I'm trying to
> modularize it. My fortran program uses a subroutine and I was trying
> to do the same thing in Python. But I'm still new so I'm having
> trouble understanding what I'm doing wrong. Here is my code:
>
> #! /usr/bin/python
> #This program takes two vectors and multiplies them
> #against a 10X10 array. It also then gives the dot product,
> #sum, and max value of the array.
>
> import Numeric
> def abc(array1,array2,dotprod,sum,maxvalue):
> """Takes two arrays and performs predetermined calculations,
>Then returns the solutions back as the same array, along
>with the dot product, sum, and max value of the array."""
> #TODO: Get this damn thing working!!
> print "Array 1 in:",array1 #Debug
> data = Numeric.zeros((10,10))
> for i in range(10):
> for j in range(10):
> data[i,j] = (i+1)+(j+1)
>
> e = Numeric.matrixmultiply(data, array1)
> g = Numeric.matrixmultiply(Numeric.transpose(data),array2)
> array1 = e
> array2 = g
> dotprod = Numeric.dot(array1,array2)
> sum = Numeric.sum(array1)
> maxvalue = array2[Numeric.argmax(array2)]
> print "Array 1 out:",array1 #Debug
>
> return array1,array2,dotprod,sum,maxvalue #<<-- Not working as I
> thought it would.
>
> x = Numeric.arange(1,11)
> y = Numeric.arange(1,11)*2
> dotp,sumx,maxv = 0,0,0 #Is this the only way to declare a variable?
>
> print 'Array X:',x
> print 'Array Y:',y
> abc(x,y,dotp,sumx,maxv)
> print 'Calling function abc'
> print 'Array X:',x
> print 'Array Y:',y
> print 'Dot Product of X and Y:',dotp
> print 'Sum of array X:',sumx
> print 'Max value of array Y:',maxv
>
> If you run it the data gets passed to the function just fine and it
> finds the right numbers. Its just getting it to pass them back thats
> not working. I put some print statements inside the function just to
> see how the data gets passed. So any ideas that would help me? If
you
> want to see the fortran code just email me.
>
> David
Hello David,
welcome to Python!
Python always returns 'something' from a function or method if nothing
is specified or there is no return you get an implicit None.
You have created a function that accepts a few arguments and processes
them then returns there value.
The problem is that you **have not** used the return values ;)
example:
def funk(first,second,third):
return first,second,third
This can be like this:
print funk("theses three args can be anything",2,"three")
If you need to use the return values you need to assign them to a
"name" so you have a handle on them.
Variables are don't exist in Python there are only objects and names(
hence namespaces ), but not everyone is so strict and you still see
mention of 'variables' when they mean 'names'.
> ##dotp,sumx,maxv = 0,0,0 # not needed here
> print 'Array X:',x
> print 'Array Y:',y
> ## Notice we assign the return values to names so we can access it
later
> arr1,arr2,dotp,sumx,maxv = abc(x,y,0,0,0)
> print 'Calling function abc'
> print 'Array X:',arr1
> print 'Array Y:',arr2
> print 'Dot Product of X and Y:',dotp
> print 'Sum of array X:',sumx
> print 'Max value of array Y:',maxv
Or you could pack all return values into a tuple and access it thru
slices.
> ##dotp,sumx,maxv = 0,0,0 # not needed here
> print 'Array X:',x
> print 'Array Y:',y
> abcinfo = abc(x,y,0,0,0)
> print 'Calling function abc'
> print 'Array X:',abcinfo[0]
> print 'Array Y:',abcinfo[1]
> print 'Dot Product of X and Y:',abcinfo[2]
> print 'Sum of array X:',abcinfo[3]
> print 'Max value of array Y:',abcinfo[4]
Or you could use a dictionary, or etc...
The possibilities are endless.
Be sure to study up on namespaces, it will ease your Python woes.
Namespaces are the most fundamental part of Python that new users don't
understand. Namespace mastery will take you far.
Just remember there are only two scopes local and global ;)
http://docs.python.org
hth,
M.E.Farmer
--
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Re: pygame on win32, image.fromstring()
"Greg Krohn" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > tlviewer wrote: > > hello, > > hi > > > fp = open( "e:/batch/python/aceclub.bmp", "wt") > > wt? Should this be wb? > > > # gives: ValueError: String length does not equal format and resolution size > > img = gm.image.fromstring(str,(71,96),"P") > > The pygame docs say "P" is for 8bit pallete indices. When I look at the > properties of aceclub.bmp, Windows says it's Bit Depth is 4. I'm not sure if > they're talking about the same thing, though. If so, you could probably use PIL > to convert the depth. Yes, that was the trouble. Based on your suggestion, I now massage the image string with PIL, then fromstring() works! obj =Image.open(StringIO.StringIO(str)) #obj.convert( mode='P') # conversion is implicit, mode is 'P' already img = gm.image.fromstring(obj.tostring(),(71,96),"P") Next I'm going to load all 53 card resources into a list (array) of strings, then write it out, pickled. That should smooth out loading the game when I use 4-6 decks (Blackjack-21). thanks for getting to my post so quickly, tlviewer -- -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
On 2005-05-14, Philippe C. Martin wrote: > You're thinking you're passing the arguments as reference That is the way Fortran handles them: [...] >> Right now I'm taking a simple program I wrote in Fortran Bernd -- Those who desire to give up freedom in order to gain security, will not have, nor do they deserve, either one. [T. Jefferson] -- http://mail.python.org/mailman/listinfo/python-list
Re: Python Documentation (should be better?)
bruno modulix a écrit : > > I fail to see why would it would be better to have to open a browser, go > to python.org, go to the doc, find the right link etc instead of just > typing dir(xxx) and/or help(xxx). > I fully agree with you. I just suspect that you are not more than me a web developper. I suppose that for this kind of guys, using a browser connected to the web is the more natural way to go ... and PHP developers are those kind of guys. This is to say that comparing the doc of PHP to the one of Python is somewhat not more relevant that comparing PHP to Python as languages. Probably even less because: - PHP developers are "naturally" presentation oriented. - it's easier to give "good" exemples when everybody is working in about the same area. Python is a very flexible tool and that makes things sometimes more difficult ... but worthy anyway. -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
Hi, You're thinking you're passing the arguments as reference (look at mutable vs non-mutable) Your function returns the values in a tupple (x,y,...); you need to fetch the values from that tupple Regards, Philippe David wrote: > Hi I'm trying to teach myself python and so far to good, but I'm having > a bit of trouble getting a function to work the way I think it should > work. Right now I'm taking a simple program I wrote in Fortran and > trying to do it in Python. I got it to work, but now I'm trying to > modularize it. My fortran program uses a subroutine and I was trying > to do the same thing in Python. But I'm still new so I'm having > trouble understanding what I'm doing wrong. Here is my code: > > #! /usr/bin/python > #This program takes two vectors and multiplies them > #against a 10X10 array. It also then gives the dot product, > #sum, and max value of the array. > > import Numeric > def abc(array1,array2,dotprod,sum,maxvalue): > """Takes two arrays and performs predetermined calculations, >Then returns the solutions back as the same array, along >with the dot product, sum, and max value of the array.""" > #TODO: Get this damn thing working!! > print "Array 1 in:",array1 #Debug > data = Numeric.zeros((10,10)) > for i in range(10): > for j in range(10): > data[i,j] = (i+1)+(j+1) > > e = Numeric.matrixmultiply(data, array1) > g = Numeric.matrixmultiply(Numeric.transpose(data),array2) > array1 = e > array2 = g > dotprod = Numeric.dot(array1,array2) > sum = Numeric.sum(array1) > maxvalue = array2[Numeric.argmax(array2)] > print "Array 1 out:",array1 #Debug > > return array1,array2,dotprod,sum,maxvalue #<<-- Not working as I > thought it would. > > x = Numeric.arange(1,11) > y = Numeric.arange(1,11)*2 > dotp,sumx,maxv = 0,0,0 #Is this the only way to declare a variable? > > print 'Array X:',x > print 'Array Y:',y > abc(x,y,dotp,sumx,maxv) > print 'Calling function abc' > print 'Array X:',x > print 'Array Y:',y > print 'Dot Product of X and Y:',dotp > print 'Sum of array X:',sumx > print 'Max value of array Y:',maxv > > If you run it the data gets passed to the function just fine and it > finds the right numbers. Its just getting it to pass them back thats > not working. I put some print statements inside the function just to > see how the data gets passed. So any ideas that would help me? If you > want to see the fortran code just email me. > > David -- http://mail.python.org/mailman/listinfo/python-list
Re: A new to Python question
On 2005-05-14, David wrote: > abc(x,y,dotp,sumx,maxv) (x,y,dotp,sumx,maxv) = abc(x,y,dotp,sumx,maxv) Bernd -- Those who desire to give up freedom in order to gain security, will not have, nor do they deserve, either one. [T. Jefferson] -- http://mail.python.org/mailman/listinfo/python-list
A new to Python question
Hi I'm trying to teach myself python and so far to good, but I'm having a bit of trouble getting a function to work the way I think it should work. Right now I'm taking a simple program I wrote in Fortran and trying to do it in Python. I got it to work, but now I'm trying to modularize it. My fortran program uses a subroutine and I was trying to do the same thing in Python. But I'm still new so I'm having trouble understanding what I'm doing wrong. Here is my code: #! /usr/bin/python #This program takes two vectors and multiplies them #against a 10X10 array. It also then gives the dot product, #sum, and max value of the array. import Numeric def abc(array1,array2,dotprod,sum,maxvalue): """Takes two arrays and performs predetermined calculations, Then returns the solutions back as the same array, along with the dot product, sum, and max value of the array.""" #TODO: Get this damn thing working!! print "Array 1 in:",array1 #Debug data = Numeric.zeros((10,10)) for i in range(10): for j in range(10): data[i,j] = (i+1)+(j+1) e = Numeric.matrixmultiply(data, array1) g = Numeric.matrixmultiply(Numeric.transpose(data),array2) array1 = e array2 = g dotprod = Numeric.dot(array1,array2) sum = Numeric.sum(array1) maxvalue = array2[Numeric.argmax(array2)] print "Array 1 out:",array1 #Debug return array1,array2,dotprod,sum,maxvalue #<<-- Not working as I thought it would. x = Numeric.arange(1,11) y = Numeric.arange(1,11)*2 dotp,sumx,maxv = 0,0,0 #Is this the only way to declare a variable? print 'Array X:',x print 'Array Y:',y abc(x,y,dotp,sumx,maxv) print 'Calling function abc' print 'Array X:',x print 'Array Y:',y print 'Dot Product of X and Y:',dotp print 'Sum of array X:',sumx print 'Max value of array Y:',maxv If you run it the data gets passed to the function just fine and it finds the right numbers. Its just getting it to pass them back thats not working. I put some print statements inside the function just to see how the data gets passed. So any ideas that would help me? If you want to see the fortran code just email me. David -- http://mail.python.org/mailman/listinfo/python-list
Anyway to designating the encoding of the "source" for compile?
Python's InteractiveInterpreter uses the built-in compile function. According to the ref. manual, it doesn't seem to concern about the encoding of the source string. When I hand in an unicode object, it is encoded in utf-8 automatically. It can be a problem when I'm building an interactive environment using "compile", with a different encoding from utf-8. IDLE itself has the same problem. ( '' is treated okay but u'' is treated wrong.) Any suggestions or any plans in future python versions? -- http://mail.python.org/mailman/listinfo/python-list
Quick Reference from module doc strings.
Does anyone have suggestions on how to improve this further?
Cheers,
Ron_Adam
def getobjs(object, dlist=[], lvl=0, maxlevel=1):
""" Retrieve a list of sub objects from an object. """
if object not in dlist:
dlist.append(object)
if lvl200:
s = object[0:200]+".."
else:
s = object
outtext.append(obj+'=')
if '\n' in s: quotes='"""'
else: quotes ='"'
if len(s)>60: print
outtext.append(quotes+s+quotes+'\n\n')
elif (isinstance(object,str)
or isinstance(object,int)
or isinstance(object,bool)
or isinstance(object,tuple)
or isinstance(object,list)
or isinstance(object,dict)):
s = str(object)
if len(s)<200:
outtext.append(obj+'='+s+'\n\n')
else:
outtext.append(obj+'='+s[0:200]+'..\n\n')
if hasattr(object,'__doc__'):
if object.__doc__ != type(object).__doc__:
outtext.append(str(object.__doc__)+'\n\n')
return ''.join(outtext)
def quick_ref(name):
"""
quick_ref(module_name) -> printable string
Generate a sorted quick reference guide from an objects
doc strings. The module_name is a string with the name of
the module or class to get documents string from.
Example:
import os
print quick_ref('os')
"""
objlist = getobjs(name)
return printdoc(objlist)
if __name__ == "__main__":
#import module before calling in most cases.
print quick_ref('__builtins__')
--
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Re: Python 2.4 & BLT ?
StepH wrote: >> >> A little googling found the following which may give you a clue or >> ideas of further searches. Also run a virus scanner on the file >> before hand. >> >> http://www.noteworthysoftware.com/composer/faq/90.htm > > > Argg... I always find me stupid when i don't have find myself a such > easy solution. Running the .exe from C:\temp works, but now, even if > the installation succes, i'm not able to run the pmw sample based on > it... Looks like i've now to re-install pmw or somethings like that. > > I'll find it... > > Thanks a lot for your help. > StepH. > Glad I could help. It's a shame BLT has the installation issues it does on windows. It really needs to be repackaged correctly. Also you will probably also need to do the following which I posted earlier on the group, but will recopy it here as well. (That way it will be easier for me to find it next time I need it. ;-) BLT doesn't install in the correct directories on Windows. I found this helpful. 1. Install BLT 2.4u into C:/Python23/tcl, using BLT's installer (the one for Tcl/Tk 8.3). This gives you bin, include, and lib subdirectories of C:/Python23/tcl, with all the BLT stuff in them. 2. Copy C:/Python23/tcl/lib/blt2.4 into C:/Python23/tcl/tcl8.3. 3. Put the BLT DLLs in a directory on your PATH (not necessarily a system directory, it just has to be on your PATH) Clipped from: http://heim.ifi.uio.no/~hpl/scripting/software.html Cheers, Ron_Adam -- http://mail.python.org/mailman/listinfo/python-list
Re: Multiple "cmp"s chained one after another
Robert Kern wrote: > I find that using the "key" argument to sort is much nicer than "cmp" > for these tasks. > > In [5]:L = [datetime.date(2005,5,2), datetime.date(1984,12,15), > datetime.date(1954,1,1)] > > In [7]:L.sort(key=lambda x: (x.month, x.day)) > > In [8]:L > Out[8]: > [datetime.date(1954, 1, 1), > datetime.date(2005, 5, 2), > datetime.date(1984, 12, 15)] Yes, definitely. Also worth noting in Robert Kern's solution is that instead of writing: def mycmp(d1, d2): return cmp(d1.month,d2.month) or cmp(d1.day,d2.day) you can write: def mycmp(d1, d2): return cmp((d1.month, d1.day), (d2.month, d2.day)) or if you're using the key= argument (like you probably should): def mykey(d): return (d.month, d.day) The point here is that rather than chaining cmp() calls with ors, you should just use a tuple -- the standard comparison order in tuples is exactly what you're looking for. STeVe -- http://mail.python.org/mailman/listinfo/python-list
Re: Encryption with Python?
Hi, I am a very happy user of http://www.amk.ca/python/code/crypto.html Regards, Philippe Blake T. Garretson wrote: > I want to save some sensitive data (passwords, PIN numbers, etc.) to > disk in a secure manner in one of my programs. What is the > easiest/best way to accomplish strong file encryption in Python? Any > modern block cipher will do: AES, Blowfish, etc. I'm not looking for > public key stuff; I just want to provide a pass-phrase. > > I found a few modules out there, but they seem to be all but abandoned. > Most seem to have died several years ago. The most promising package > is A.M. Kuchling's Python Cryptography Toolkit > (http://www.amk.ca/python/code/crypto.html). > > Is this the defacto Python encryption solution? What does everyone > else use? Any other suggestions? The SSLCrypto package > (http://www.freenet.org.nz/python/SSLCrypto/) may be a good alternative > too, but I am not sure if it is actively maintained. > > Thanks, > Blake -- http://mail.python.org/mailman/listinfo/python-list
Re: Build-in or user-defined exceptions?
Torsten Bronger wrote: > I write a module, and so I must raise exceptions at several points. > The PEP 8 says that a module should define their own exceptions base > class, derived from "Exception", and derivatives of that. > > However, the build-in exceptions cover most of the error types that > occur in a standard program. For example, my module communicates > with measurement instruments, so any communication error would fit > perfectly to the build-in "IOError", wouldn't it? No... *any* communication error? What if it's an error in the serial port layer, or the protocol layer, or the application layer handling that communication? Wouldn't SerialError, ProtocolError, or UnrecognizedResponseError (or things like that) be much more readable. I find fine-grained app-specific exceptions to be very helpful in writing code that talks to machines. > Invalid arguments > can raise "TypeError"s, and so on and so forth. Likewise, RangeError, InvalidAddressError, and the like seem more helpful to me, most of the time. I guess I pretty much follow PEP8 (though I don't recall its details right now) since I derive from Exception things like DriverError and then derive more specific exceptions from that as needed (in the case of a driver module), or ProtocolError and children, etc.. > Is it considered good style to raise build-in exceptions whereever > one thinks it's appropriate? Is the definition of module exceptions > derived from "IOError", "TypeError" etc. a good idea? Is there some > sort of style guide for recommended exceptions design in Python? As Fredrik recommends, use your own judgment, but I believe that one should use a very narrow definition for those exceptions. For example, TypeError should be used specifically when the code involved has received an object of the wrong type and *not* (for example) when a driver receives the wrong "type" of command from another device. I sometimes derive from things like ValueError (rather than just Exception) when it seems appropriate, but that's pretty rare, and it's also not what the docs themselves recommend. Be guided by the descriptions of those exceptions in the docs and not by their names alone. See http://docs.python.org/lib/module-exceptions.html for more and be sure to read the descriptions of the base classes, not just the subclasses. -Peter -- http://mail.python.org/mailman/listinfo/python-list
Re: Multiple "cmp"s chained one after another
vincent wehren wrote: > "Volker Grabsch" <[EMAIL PROTECTED]> schrieb im > Newsbeitrag news:[EMAIL PROTECTED] > | However, I don't want to sort them the default way. These are birthdays, > | so only the month and day do matter, not the year. E.g.: > | ... > If you don't care about the year, why not just "normalize" the year > to all be the same using the replace method of the date instance? > Something like: > > d1 = datetime.date(2004, 12, 2) > d2 = datetime.date(2001, 12, 3) > d3 = datetime.date(2002, 12, 6) > d4 = datetime.date(1977, 12, 7) > dates =[d1,d2,d3,d4] > datesNorm = [obj.replace(year=1900) for obj in (dates)] > datesNorm.sort() > print datesNorm # etcetera Or just use the .timetuple() method on datetime objects and sort on the 8th element of the 9-element tuple, which is the day-of-the-year. -Peter -- http://mail.python.org/mailman/listinfo/python-list
Re: Build-in or user-defined exceptions?
Torsten Bronger wrote: > Is it considered good style to raise build-in exceptions whereever > one thinks it's appropriate? yes. > Is the definition of module exceptions derived from "IOError", "TypeError" > etc. a good idea? sure (when absolutely necessary). > Is there some sort of style guide for recommended exceptions design in > Python? just use your intuition. -- http://mail.python.org/mailman/listinfo/python-list
Re: function with variable arguments
Xah Lee wrote: > I think it would be a improvement for the built-in range() so that step > needs not be an integer. [...] > > Range( 5, 7, 0.3); # returns [5, 5.3, 5.6, 5.9, 6.2, 6.5, 6.8] This may not return what you expect it to return. For example let's use a naive implementation like this: def Range(start, stop, step): values = [] while start < stop: values.append(start) start += step return values The result is: >>> Range(5, 7, 0.3) [5, 5.2998, 5.5996, 5.8995, 6.1993, 6.4991, 6.7989] Worse: Range(5, 7.1, 0.3) would return 8 values, not 7 as expected from e.g. range(50, 71, 3). Welcome to the interesting world of floating point numbers. Harald -- http://mail.python.org/mailman/listinfo/python-list
Re: A question about inheritance
Ok, thanks. I didn't know about new-style classes (I had learned python from a book prior to them). After reading about new-style classes, I find that your solution is better because, using super (in general) avoids cl2 from having to know the implementation details of cl1. This is clearly explained in: http://www.python.org/2.2.3/descrintro.html#cooperation Also, when using new-style classes with IDLE, I found some problems which I talk about in "Modifying CallTips.py to work with with new-style classes in IDLE.", which I posted in this group. Steven Bethard wrote: > [EMAIL PROTECTED] wrote: > > Hello I have a question about inheritance in Python. I'd like to do > > something like this: > > > > class cl1: > > def __init__(self): > >self.a = 1 > > > > class cl2(cl1): > > def __init__(self): > >self.b = 2 > > > > But in such a way that cl2 instances have atributes 'b' AND 'a'. > > Obviously, this is not the way of doing it, because the __init__ > > definition in cl2 overrides cl1's __init__. > > > > Is there a 'pythonic' way of achieving this? > > If there's a chance you might have multiple inheritance at some point in > this hierarchy, you might also try using super: > > class cl1(object): # note it's a new-style class > def __init__(self): > self.a = 1 > > class cl2(cl1): > def __init__(self): > super(cl2, self).__init__() > self.b = 2 > > Note that you probably want a new-style class even if you chose not to > use super in favor of Jp Calderone's suggestion. There are very few > cases for using old-style classes these days. > > STeVe -- http://mail.python.org/mailman/listinfo/python-list
Re: replace text in unicode string
On 14 May 2005 02:23:55 -0700, "Dan Bishop" <[EMAIL PROTECTED]> wrote:
>Svennglenn wrote:
>> I'm having problems replacing text in a
>> unicode string.
>> Here's the code:
>>
>> # -*- coding: cp1252 -*-
>>
>> titel = unicode("ä", "iso-8859-1")
To the OP:
This is not causing the later problem, but it's evidence of the wrong
mindset for a start. You have just lied to the interpreter. You said
that your script was encoded using cp1252, but then you tried to pass
off a string constant as iso-8859-1!!! They are not exactly the same
repertoire. You need to make up your mind what character repertoire
your application should be confined to, and then apply that
restriction rigorously.
To get over the error message, all you need to do is this:
titel = u"ä"
... and didn't I (and/or somebody else) tell you this only a few days
ago?
>> print titel
>> print type(titel)
>>
>> titel.replace("ä", "a")
>>
>> When i run this program I get this error:
>>
>> titel.replace("ä", "a")
>> UnicodeDecodeError: 'ascii' codec can't decode byte 0xe4 in position
>0:
>> ordinal not in range(128)
>>
>> How can i replace text in the Unicode string?
>
>titel = titel.replace(u"ä", "a")
To Dan:
Fortuitously this works but if the OP wanted to change it to (say) an
umlauted-u then it would have thrown another UnicodeDecodeError.
Everybody please get into the habit of using u"blah blah" when you're
working with Unicode.
Like this:
titel = titel.replace(u"ä", u"a")
--
http://mail.python.org/mailman/listinfo/python-list
Build-in or user-defined exceptions?
HallÃchen! I write a module, and so I must raise exceptions at several points. The PEP 8 says that a module should define their own exceptions base class, derived from "Exception", and derivatives of that. However, the build-in exceptions cover most of the error types that occur in a standard program. For example, my module communicates with measurement instruments, so any communication error would fit perfectly to the build-in "IOError", wouldn't it? Invalid arguments can raise "TypeError"s, and so on and so forth. Is it considered good style to raise build-in exceptions whereever one thinks it's appropriate? Is the definition of module exceptions derived from "IOError", "TypeError" etc. a good idea? Is there some sort of style guide for recommended exceptions design in Python? Thank you! TschÃ, Torsten. -- Torsten Bronger, aquisgrana, europa vetus -- http://mail.python.org/mailman/listinfo/python-list
Re: win32com and apache and permissions
found the answer five minutes after posting the question. Isn't that always the way? I had not granted the Apache user permission to launch IE. To do so: * launch DCOMCNFG.exe * choose "internet explorer" and click "properties" * choose the "security" tab and and "custom launch permissions" * "edit permissions", then "add" * choose "Users", then click "show users" * choose the "apache" user and click "add" * "OK" your way out of there. -- http://mail.python.org/mailman/listinfo/python-list
problem uploading ZIP file tp PyPI
Sorry in advance if this is not the correct forum ... I'm trying to upload what appears to be a perfectly OK zip file as a "source" file type to PyPI, and am getting this response: Error... There's been a problem with your request exceptions.ValueError: invalid distribution file I have managed to upload a Windows installer, and downloaded it again [but the download count is still stuck on zero]. Any clues? -- http://mail.python.org/mailman/listinfo/python-list
win32com and apache and permissions
I'm trying to have a Python script (which is being launched by Apache as a CGI) control Internet Explorer. I have this working on my development box, but when I moved the code to my integration test box, I get "Access Denied" when trying to launch IE. This only seems to happen when running Apache as a service. If I run apache as a console app, everything works fine. In summary: User Method Dev Box Integration Box AdministratorConsole Works Works AdministratorService Works "Access Denied" Apache Console Works Works Apache Service Not permitted Not permitted So somewhere, somehow, I think I've granted some permission on the dev box that I have not granted on the integration box. Can anyone think of what it might be? -Chris -- http://mail.python.org/mailman/listinfo/python-list
Re: Multiple "cmp"s chained one after another
Volker Grabsch wrote: > Hello! > > Ich just found a very nice 'pythonic' solution for an often appearing > problem. I didn't find it documented anywhere, so I'm posting it here. > If this isn't new in any way, I'd really like to get to know it. > > Example problem: > I have some "datetime" objects and want to sort them, as here: > > birthdays = [d1,d2,d3,d4] > birthdays.sort() > > However, I don't want to sort them the default way. These are birthdays, > so only the month and day do matter, not the year. E.g.: > > 2003-01-01 should be smaller than 1984-05-01 [snip] > Any opinions? I find that using the "key" argument to sort is much nicer than "cmp" for these tasks. In [5]:L = [datetime.date(2005,5,2), datetime.date(1984,12,15), datetime.date(1954,1,1)] In [7]:L.sort(key=lambda x: (x.month, x.day)) In [8]:L Out[8]: [datetime.date(1954, 1, 1), datetime.date(2005, 5, 2), datetime.date(1984, 12, 15)] -- Robert Kern [EMAIL PROTECTED] "In the fields of hell where the grass grows high Are the graves of dreams allowed to die." -- Richard Harter -- http://mail.python.org/mailman/listinfo/python-list
Re: function with variable arguments
Xah Lee wrote: > on a related topic, > I think it would be a improvement for the built-in range() so that step > needs not be an integer. There are easy workarounds but I'd find it useful as well. > Further, it'd be better to support decreasing range. e.g. > > Range( 5, 7, 0.3); # returns [5, 5.3, 5.6, 5.9, 6.2, 6.5, 6.8] > Range( 5, -4, -2); # returns [5,3,1,-1,-3] The last one already works: >>> range(5,-4,-2) [5, 3, 1, -1, -3] -- http://mail.python.org/mailman/listinfo/python-list
Re: wxTimer problem
As Jp asked already: "indepenedent" from what? I do such things all the time in a wx-App that controls a 6-axes robot. For example, there I have a LED-Widget for displaying the actual pos. and orient. of the tool. In a wxTimer handler I read OPC variables, whose values are displayed in the LED-Widgets (the 6 LED-widgets make up a compound widget that does the data retreival in a wxTimer handler). My app is full of widgets that own a timer to display current values. As for "independent": If you wrote a GUI app in wx you'll want to display those values coming from some COM objects. So simply tie a timer to the widget that should display it and - do it. Or tie it to the frame containing your widget. It's up to you - plenty of possibilities in wx/Python, and total freedom (I know what I'm speakin' of, I started that app in VB...). Kind regards Franz GEIGER "Jp Calderone" <[EMAIL PROTECTED]> schrieb im Newsbeitrag news:[EMAIL PROTECTED] > On Fri, 13 May 2005 14:57:26 +0800, Austin <[EMAIL PROTECTED]> wrote: > >I wrote a GUI program on windows. (python & wxPython) > >One function is to refresh the data from the COM Object continously. > >In the beginning, I used the thread.start_new_thread(xxx,()) > >But no matter how i try, it will cause the win32com error. > > > >After that, i use the wx.Timer to do the refresh function. > >It works fine, but i find one problem. > >I think timer should be independant, just like thread, but wxTimer doesn't. > > > >1. Does python have timer function( not included by thread)? > >2. About the wxTimer, does any parameter to let it be independent? > > > > What does "independent" mean? > > Jp -- http://mail.python.org/mailman/listinfo/python-list
Re: Importing modules
CONTEXT: Trying to modularize (is this english?) application development : MVC style, team distributed so that a visual component can be in one module imported and used by the __main__, and connected (read packed) at runtime to other components coming from the main or other modules. PROBLEM: After reading the above reference (and the Nutshell chapter) and trying different importing variations I still have a very difficult time understanding this situation. 1-importing Tkinter in main, 2-importing module that uses Tkinter, without importing Tkinter in that module (DOES NOT WORK) KLUDGED SOLUTION: import Tkinter in module (but don't understand why it has to be this way) MODEL (I taught would work): ## importTestMain module from Tkinter import * import testModule tata = testModule.toto() ## this works myWidget = tata.createNewFrame() ## this gets the exception (see below) ... ## testModule class toto(object): def __init__(self): self.someAttribute= 2 def createNewFrame(self): self.myFrame = Frame()## culprit line in exception return f if __main__=='__name__': ## team member tests is work here (does work!) from Tkinter import * myInstance = otherModule.toto() myWidget = myInstance.createNewFrame() root=Tk() myWidget.pack(in_=root) root.mainloop() The exception says : Traceback (most recent call last): File "C:\Python23\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py", line 310, in RunScript exec codeObject in __main__.__dict__ File "C:\jean_marc\exemples_code_source\modules_packages\import_test\importTestMain.py", line 18, in ? tata=toto() File "C:\jean_marc\exemples_code_source\modules_packages\import_test\importTestMain.py", line 10, in __init__ self.myNewFrame = self.myTestModuleObject.createNewFrame(self.myInterModuleTestCommand) File "C:\jean_marc\exemples_code_source\modules_packages\import_test\testModule.py", line 8, in createNewFrame self.myFrame = Frame() NameError: global name 'Frame' is not defined >>> VARIATION Imported testModule AFTER using Tkinter in main... same error :( -- http://mail.python.org/mailman/listinfo/python-list
Re: Multiple "cmp"s chained one after another
"Volker Grabsch" <[EMAIL PROTECTED]> schrieb im
Newsbeitrag news:[EMAIL PROTECTED]
| Hello!
|
| Ich just found a very nice 'pythonic' solution for an often appearing
| problem. I didn't find it documented anywhere, so I'm posting it here.
| If this isn't new in any way, I'd really like to get to know it.
|
| Example problem:
| I have some "datetime" objects and want to sort them, as here:
|
| birthdays = [d1,d2,d3,d4]
| birthdays.sort()
|
| However, I don't want to sort them the default way. These are birthdays,
| so only the month and day do matter, not the year. E.g.:
|
| 2003-01-01 should be smaller than 1984-05-01
|
| So I have to write the comparison on my own, e.g.
|
| def cmp_birthdays(d1,d2):
| if d1.month > d2.month: return 1
| if d1.month < d2.month: return -1
| if d1.day > d2.day: return 1
| if d1.day < d2.day: return -1
| return 0
|
| ...
| birthdays.sort(cmp_birthdays)
If you don't care about the year, why not just "normalize" the year
to all be the same using the replace method of the date instance?
Something like:
d1 = datetime.date(2004, 12, 2)
d2 = datetime.date(2001, 12, 3)
d3 = datetime.date(2002, 12, 6)
d4 = datetime.date(1977, 12, 7)
dates =[d1,d2,d3,d4]
datesNorm = [obj.replace(year=1900) for obj in (dates)]
datesNorm.sort()
print datesNorm # etcetera
HTH,
---
Vincent
|
| This implementation of cmp_birthdays is very ugly. Image you want to
| chain more than 2 values in that "cmp_birthdays". I also want to use the
| builtin "cmp" function, not ">" and "<".
|
| After thinking some minutes about it, I found a very nice solution:
| I have some "cmp"s one aftter another. If one if them return 1 oder -1,
| it sould be returned. If it returns 0, the next "cmp" is used. In other
| words: I have a sequence of numbers, and want to get the first one that
| is not 0. (or return 0, if all numbers were 0)
|
| But this is exactly what the "or" operator does, due to short-circuit
| evaluation. In this example, that means:
|
| def cmp_bithdays(d1,d2):
| return cmp(d1.month,d2.month) or cmp(d1.day,d2.day)
|
| The generic pattern is:
|
| return cmp(...) or cmp (...) or cmp(...) or ...
|
| I'm not sure whether this pattern is already a "common recipe", but
| I found it to be a very nice idea. :-)
|
| Any opinions?
|
|
| Greets,
|
| Volker
|
| --
| Volker Grabsch
| ---<<(())>>---
| \frac{\left|\vartheta_0\times\{\ell,\kappa\in\Re\}\right|}{\sqrt
| [G]{-\Gamma(\alpha)\cdot\mathcal{B}^{\left[\oint\!c_\hbar\right]}}}
--
http://mail.python.org/mailman/listinfo/python-list
Modifying CallTips.py to work with with new-style classes in IDLE.
When using Idle, Call Tips are floating windows which display function, class, and method parameter and docstring information when you type an opening parenthesis, and which disappear when you type a closing parenthesis. But when you use new-style classes, they don't work fine and don't show the arguments of the __init__ method. There is a topic in this newsgroup (new style classes and an IDLE "grump"), where a solution was given to the problem (in Mar 27 2002): > The solution seems to be simply changing line 115 in CallTips.py (in the > Tools/Idle/ directory) as folows: > > if type(ob)==types.ClassType: > > to > > if type(ob)==types.ClassType or type(ob) == types.TypeType: I've tried it (Python 2.4.1 - IDLE 1.1.1) and it works fine (CallTips was in the \Lib\idlelib directory for me). Why isn't this the default behaviour? Is this the right place to post this? -- http://mail.python.org/mailman/listinfo/python-list
Re: 80 bit precision ?
"km" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > Hi all, > > does python currently support 80 bit precision Floating Point Unit ? > > regards, > KM I've just been using the decimal module for Python 2.3 (native in Python 2.4) at 100 digit precision to solve some very high order polynomials. Slow but worked well for me. Also used a rational.py module ported to Py 2.3. Perhaps you can do your calcs to the precision you want with a combination of decimal and rational arithmetic. bwaha -- http://mail.python.org/mailman/listinfo/python-list
Re: Returning Date As String ?
Peter Moscatt <[EMAIL PROTECTED]> wrote: > I am wanting to return the system date using the following: > > date.today() > > How would I then convert this to a string ? > > Pete datetime.data objects have a __str__() method. To convert one to a string, you just have to cause its __str__() to be invoked. The most common ways of doing that are str(), %s, or print: >>> import datetime >>> d = datetime.date.today() >>> d datetime.date(2005, 5, 14) # this is the repr() of the object >>> print d 2005-05-14 >>> str(d) '2005-05-14' >>> '%s' % d '2005-05-14' -- http://mail.python.org/mailman/listinfo/python-list
Re: Python 2.4 & BLT ?
Ron Adam a écrit : > StepH wrote: > >> Ron Adam a écrit : >> >>> StepH wrote: >>> >>> Ron Adam a écrit : > StepH wrote: > > > >> Hi, >> >> I'm not able to install BLT on my Python 2.4 (upgraded to 2.4.1) >> distibution... >> >> I'v try to download btlz-for-8.3.exe, but when i try to install >> it, i've a msgbox saying to the file is corrupt... >> >> Any idea ? >> >> Thanks. >> >> StepH. > > > > > Have you tried blt2.4z-for-8.4exe? > > http://blt.sourceforge.net yes. When i try to execute it, a small msgbox apprea with the msg: Corrupt installation detected! Any idea ? >>> >>> >>> >>> Sounds like it might not be a corrupted install exe file, but a >>> previously installed version that is corrupted. >>> >> >> >> Hum, i've try to re-install all from scratch without success... >> >> >>> Does the message box say anything else? With just "Corrupt >>> installation detected!", it could also be a support file or missing >>> dll that the installer needs. >> >> >> >> Yes. It's the only message that is displayed. >> I've to go ahead... so for now i'll use tk.Canvas for my display... >> >> If you have idea ? > > > A little googling found the following which may give you a clue or ideas > of further searches. Also run a virus scanner on the file before hand. > > http://www.noteworthysoftware.com/composer/faq/90.htm Argg... I always find me stupid when i don't have find myself a such easy solution. Running the .exe from C:\temp works, but now, even if the installation succes, i'm not able to run the pmw sample based on it... Looks like i've now to re-install pmw or somethings like that. I'll find it... Thanks a lot for your help. StepH. > http://www.transcender.com/faqs/detail.aspx?pn=tradwnldinstallarticle00900&full=True&tree=True > > > http://www.visagesoft.com/help/index.php?_a=knowledgebase&_j=questiondetails&_i=5 > > > http://www.wise.com/KBArticle.aspx?articleno=1034 > > As a last resort, you may also be able to check the exe file by using a > zip file reader such as winzip or powerarchiver. You should be able to > extract the individual files that way, but it may be a bit of a task to > figure out where to put them. > > Hope this helps, > > _Ron -- http://mail.python.org/mailman/listinfo/python-list
Python on a public library computer
Here's my situation: I'm typing this in a public library on a computer with OS windows 2000 server. I can run Internet explorer, word, excel and powerpoint, that's it. Maybe java, but it seems to be flaky. I want to run python scripts from this computer. At home I have a multi-computer network (from better times) but no internet access anymore, I could use this to try out solutions. I also have access to a friends computer which has internet connection, but I can't visit his place all the time. He's away often but he's got a life of his own :-) So I'm thinking of running some kind of python webserver from a dedicated computer over there (visualizing some cherrypy webpage based interpreter at the moment) but I would like to know other options. However it would have to run from a webpage here ... For example I would like to run a python script over there (e.g. getting news from a usenet server) which puts the output in a zipfile on another webpage so that I can fetch it here with the Internet Explorer. There seems to be no traffic load problem since there would be only a few users (but it could become popular fast?). Also I'm worried about security issues, but not so much that I would consider installing some large scale payware professional solution. Let me know what you think, unless it costs money. On the other hand money would solve this problem so if I can do something to get that it would be even better. Anton [the things they make you go through ...] -- http://mail.python.org/mailman/listinfo/python-list
Re: Returning Date As String ?
if you're using date.today(): x=date.today() -- http://mail.python.org/mailman/listinfo/python-list
Returning Date As String ?
I am wanting to return the system date using the following: date.today() How would I then convert this to a string ? Pete -- http://mail.python.org/mailman/listinfo/python-list
Re: function with variable arguments
Thanks to all for the reply. (i should've known better) on a related topic, I think it would be a improvement for the built-in range() so that step needs not be an integer. Further, it'd be better to support decreasing range. e.g. Range( 5, 7, 0.3); # returns [5, 5.3, 5.6, 5.9, 6.2, 6.5, 6.8] Range( 5, -4, -2); # returns [5,3,1,-1,-3] Xah [EMAIL PROTECTED] â http://xahlee.org/ -- http://mail.python.org/mailman/listinfo/python-list
Multiple "cmp"s chained one after another
Hello!
Ich just found a very nice 'pythonic' solution for an often appearing
problem. I didn't find it documented anywhere, so I'm posting it here.
If this isn't new in any way, I'd really like to get to know it.
Example problem:
I have some "datetime" objects and want to sort them, as here:
birthdays = [d1,d2,d3,d4]
birthdays.sort()
However, I don't want to sort them the default way. These are birthdays,
so only the month and day do matter, not the year. E.g.:
2003-01-01 should be smaller than 1984-05-01
So I have to write the comparison on my own, e.g.
def cmp_birthdays(d1,d2):
if d1.month > d2.month: return 1
if d1.month < d2.month: return -1
if d1.day > d2.day: return 1
if d1.day < d2.day: return -1
return 0
...
birthdays.sort(cmp_birthdays)
This implementation of cmp_birthdays is very ugly. Image you want to
chain more than 2 values in that "cmp_birthdays". I also want to use the
builtin "cmp" function, not ">" and "<".
After thinking some minutes about it, I found a very nice solution:
I have some "cmp"s one aftter another. If one if them return 1 oder -1,
it sould be returned. If it returns 0, the next "cmp" is used. In other
words: I have a sequence of numbers, and want to get the first one that
is not 0. (or return 0, if all numbers were 0)
But this is exactly what the "or" operator does, due to short-circuit
evaluation. In this example, that means:
def cmp_bithdays(d1,d2):
return cmp(d1.month,d2.month) or cmp(d1.day,d2.day)
The generic pattern is:
return cmp(...) or cmp (...) or cmp(...) or ...
I'm not sure whether this pattern is already a "common recipe", but
I found it to be a very nice idea. :-)
Any opinions?
Greets,
Volker
--
Volker Grabsch
---<<(())>>---
\frac{\left|\vartheta_0\times\{\ell,\kappa\in\Re\}\right|}{\sqrt
[G]{-\Gamma(\alpha)\cdot\mathcal{B}^{\left[\oint\!c_\hbar\right]}}}
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Re: 80 bit precision ?
Terry Reedy a écrit : > [...] > Last I read, in CPython, the float type encapsulates a C double. > So, does any C compiler implements doubles as 80 bit floats? I seriously doubt it. > Or, if it has 64 bit > doubles and 80 bit long doubles, are the latter transparently > substitutible for the former, so that you could change Python's > float declaration and have everything work as expected? (I an > not sure of either.) Mm ... the python C code implementing the math module is probably not that polymorphic . Even a call to "sqrt" does not work as expected if the argument is a long double. "sqrtl" should be use instead. Cheers, SB -- http://mail.python.org/mailman/listinfo/python-list
Re: replace text in unicode string
Svennglenn wrote:
> I'm having problems replacing text in a
> unicode string.
> Here's the code:
>
> # -*- coding: cp1252 -*-
>
> titel = unicode("ä", "iso-8859-1")
> print titel
> print type(titel)
>
> titel.replace("ä", "a")
>
> When i run this program I get this error:
>
> titel.replace("ä", "a")
> UnicodeDecodeError: 'ascii' codec can't decode byte 0xe4 in position
0:
> ordinal not in range(128)
>
> How can i replace text in the Unicode string?
titel = titel.replace(u"ä", "a")
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