pygame: output to file?
HI. is there a way to convert the graphical output of a pygame application to a mpeg file or better an animated gif? i mean, not using an external capture program... bye -- http://mail.python.org/mailman/listinfo/python-list
Re: pygame: output to file?
alex23 ha scritto: On Apr 16, 7:34 pm, superpollo wrote: is there a way to convert the graphical output of a pygame application to a mpeg file or better an animated gif? i mean, not using an external capture program... There is, but it's probably not going to be as performant as using something external: http://stackoverflow.com/questions/6087484/how-to-capture-pygame-screen but where in the code should i put the line: pygame.image.save(window, "screenshot.jpeg") ? tia bye -- http://mail.python.org/mailman/listinfo/python-list
Re: pygame: output to file?
superpollo ha scritto: alex23 ha scritto: On Apr 16, 7:34 pm, superpollo wrote: is there a way to convert the graphical output of a pygame application to a mpeg file or better an animated gif? i mean, not using an external capture program... There is, but it's probably not going to be as performant as using something external: http://stackoverflow.com/questions/6087484/how-to-capture-pygame-screen but where in the code should i put the line: pygame.image.save(window, "screenshot.jpeg") i mean, if i would want to capture ALL the frames in a video file... i ask this becase this line captures just one frame and overwrites over the successive ones... bye -- http://mail.python.org/mailman/listinfo/python-list
simple cgi program
hi clp.
i would like to submit the following code for review. it is a simple
common gateway interface program, which uses the least possible
libraries for the sake of mechanism undertanding.
the third option in the firts conditional is for commandline testing.
bye.
code follows as:
#!/usr/bin/env python
import sys
import os
import urllib as url
me = os.path.basename(sys.argv[0])
env = os.environ
method = "POST"
data=None
if env.get("REQUEST_METHOD") == "GET":
data = env.get("QUERY_STRING")
elif env.get("REQUEST_METHOD") == "POST":
data = sys.stdin.read(int(env.get("CONTENT_LENGTH")))
elif not env.get("REQUEST_METHOD"):
data = sys.stdin.readline().rstrip("\n")
if not data:
sys.stdout.write("Content-type: text/html\n\n")
sys.stdout.write("\n" % (me , method))
sys.stdout.write("TYPE A DIGIT SEQUENCE AND HIT [ENTER]:\n")
sys.stdout.write("\n")
sys.stdout.write("\n")
else:
name = data.partition("=")[0]
encvalue = data.partition("=")[2]
decvalue = url.unquote_plus(encvalue)
sys.stdout.write("Content-type: text/plain\n\n")
sys.stdout.write("method: %s\n" % method)
sys.stdout.write("data: %s\n" % data)
sys.stdout.write("name: %s\n" % name)
sys.stdout.write("encvalue: %s\n" % encvalue)
sys.stdout.write("decvalue: %s\n" % decvalue)
if decvalue.isdigit():
sys.stdout.write("the sequence you typed is: %s\n" % decvalue)
else:
sys.stdout.write("what you typed is not a valid sequence\n")
criticism and advice are appreciated!
--
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Re: simple cgi program
D'Arcy J.M. Cain ha scritto: On Sun, 17 Jan 2010 15:15:12 +0100 superpollo wrote: hi clp. i would like to submit the following code for review. it is a simple common gateway interface program, which uses the least possible libraries for the sake of mechanism undertanding. Why not just use the cgi module? It does all that for you. yes, but i am trying to learn exactly the cgi mechanism internals, just for fun ;-) -- http://mail.python.org/mailman/listinfo/python-list
Re: substitution
superpollo ha scritto: hi. what is the most pythonic way to substitute substrings? eg: i want to apply: foo --> bar baz --> quux quuux --> foo so that: fooxxxbazyyyquuux --> barxxxquuxyyyfoo bye i explain better: say the subs are: quuux --> foo foo --> bar baz --> quux then i cannot apply the subs in sequence (say, .replace() in a loop), otherwise: fooxxxbazyyyquuux --> fooxxxbazyyyfoo --> barxxxbazyyybar --> barxxxquuxyyybar not as intended... -- http://mail.python.org/mailman/listinfo/python-list
substitution
hi. what is the most pythonic way to substitute substrings? eg: i want to apply: foo --> bar baz --> quux quuux --> foo so that: fooxxxbazyyyquuux --> barxxxquuxyyyfoo bye -- http://mail.python.org/mailman/listinfo/python-list
Re: substitution
it looked simpler when i posted, but i realize that the problem is non trivial. thanks to everybody. i guess that the algorithm would be easier if it was known in advance that the string to substitute must have some specific property, say: 1) they all must start with "XYZ" 2) they all have the same length N (e.g. 5) like this: qweXYZ12asdXYZ1345XYZ ---> qweIWAS12asdIWAS1345XYZ bye -- http://mail.python.org/mailman/listinfo/python-list
not and is not problem
hi:
#!/usr/bin/env python
data = "seq=123"
name , value = data.split("=")
print name
print value
if not name == "seq":
print "DOES NOT PRINT OF COURSE..."
if name is not "seq":
print "WTF! WHY DOES IT PRINT?"
help please.
bye
--
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Re: What is a list compression in Python?
Kit ha scritto: Hello Everyone, I am not sure if I have posted this question in a correct board. Can anyone please teach me: What is a list compression in Python? Would you mind give me some list compression examples? Thanks & really appreciate that. Kit i think that's compreHENsion... http://www.python.org/doc/2.5.4/tut/node7.html#SECTION00714 -- http://mail.python.org/mailman/listinfo/python-list
Re: [ANN] Data Plotting Library DISLIN 10.0
Helmut Michels ha scritto: Dear Pytnon users, I am pleased to announce version 10.0 of the data plotting software DISLIN. why dont you make it free software (i mean. GPL'ed) bye -- http://mail.python.org/mailman/listinfo/python-list
off topic but please forgive me me and answer
how much is one half times one half? -- http://mail.python.org/mailman/listinfo/python-list
Re: off topic but please forgive me me and answer
Patrick Maupin ha scritto: On Apr 2, 2:41 pm, Andreas Waldenburger wrote: While everyone else is mocking you: Can you please elaborate on why you want to know and what kind of problem you're trying to solve with this? Also, don't you think you should have picked a maths forum for this kind of question? Methinks the OP is fluent in the way of choosing newsgroups. According to google, he has posted 6855 messages in 213 groups. http://groups.google.com/groups/profile?enc_user=ul3SQhIYmLD0Oj5Yxp-liP3Vw9uApbyajUBv9M9XLUB2gqkZmQ And I can't speak for anybody else, but I just assumed it was an April Fool's question. I meant to be laughing with the OP, not at him, so sorry if I misunderstood. no no you understood prfectly *but* the thing is i am a regular in an italian language math ng which is haunted by a crackpot who insists that 1/2 * 1/2 cannot be 1/4, "because multiplication means getting bigger", so i took a semi-serious stance and made a few posts as a statistical tentative to "convince" said crackpot that the world is not going crazy (but maybe he is) thanks ps: note that my nickname is not unique, and there are a few people whith the same one... and i didn't ever post using googlegroups -- http://mail.python.org/mailman/listinfo/python-list
Re: off topic but please forgive me me and answer
Steve Holden ha scritto:
superpollo wrote:
Patrick Maupin ha scritto:
On Apr 2, 2:41 pm, Andreas Waldenburger
wrote:
While everyone else is mocking you: Can you please elaborate on why you
want to know and what kind of problem you're trying to solve with this?
Also, don't you think you should have picked a maths forum for this
kind of question?
Methinks the OP is fluent in the way of choosing newsgroups.
According to google, he has posted 6855 messages in 213 groups.
http://groups.google.com/groups/profile?enc_user=ul3SQhIYmLD0Oj5Yxp-liP3Vw9uApbyajUBv9M9XLUB2gqkZmQ
And I can't speak for anybody else, but I just assumed it was an April
Fool's question. I meant to be laughing with the OP, not at him, so
sorry if I misunderstood.
no no you understood prfectly *but* the thing is i am a regular in an
italian language math ng which is haunted by a crackpot who insists that
1/2 * 1/2 cannot be 1/4, "because multiplication means getting bigger",
so i took a semi-serious stance and made a few posts as a statistical
tentative to "convince" said crackpot that the world is not going crazy
(but maybe he is)
thanks
ps: note that my nickname is not unique, and there are a few people
whith the same one... and i didn't ever post using googlegroups
If you think you will persuade a crackpot to drop his lunacy by logical
argument you are clearly an optimist of the first water. But since I
like a challenge (and bearing in mind this is OT so I don't claim to be
an expert) you might try first of all persuading him to agree to the
commutativity of multiplication (i.e. x * y == y * x for any x and y).
If he agrees to that, then get him to agree that x * 1 == x for any x.
If he agrees to that
he does not, since "you cannot multiply something, and not getting some
more of it" ... he is stuck with the latin etimology of "multiply"
("multiplicare" means "increase quantity", like in the fish and bread
miracle)
--
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Re: off topic but please forgive me me and answer
Mensanator ha scritto: On Apr 3, 8:00 am, superpollo wrote: Patrick Maupin ha scritto: On Apr 2, 2:41 pm, Andreas Waldenburger wrote: While everyone else is mocking you: Can you please elaborate on why you want to know and what kind of problem you're trying to solve with this? Also, don't you think you should have picked a maths forum for this kind of question? Methinks the OP is fluent in the way of choosing newsgroups. According to google, he has posted 6855 messages in 213 groups. http://groups.google.com/groups/profile?enc_user=ul3SQhIYmLD0Oj5Y... And I can't speak for anybody else, but I just assumed it was an April Fool's question. I meant to be laughing with the OP, not at him, so sorry if I misunderstood. no no you understood prfectly *but* the thing is i am a regular in an italian language math ng which is haunted by a crackpot who insists that 1/2 * 1/2 cannot be 1/4, "because multiplication means getting bigger", so i took a semi-serious stance and made a few posts as a statistical tentative to "convince" said crackpot that the world is not going crazy (but maybe he is) I seriously doubt your crackpot friend actually believes that. Probably more troll than crackpot. Showing him articles and programs that prove your premise will accomplish nothing. probably so, but you cannot imagine the traffic he generates... However, if you personally wanted information on programming with rational numbers, you came to the right place. thanks ps: note that my nickname is not unique, and there are a few people whith the same one... and i didn't ever post using googlegroups What does it mean, "super chicken? yea! http://www.renegadechickens.com/chickens/Toons/superchicken.gif -- http://mail.python.org/mailman/listinfo/python-list
Re: off topic but please forgive me me and answer
Patrick Maupin ha scritto: On Apr 3, 8:00 am, superpollo wrote: sorry if I misunderstood. no no you understood prfectly *but* the thing is i am a regular in an italian language math ng which is haunted by a crackpot who insists that 1/2 * 1/2 cannot be 1/4, "because multiplication means getting bigger", so i took a semi-serious stance and made a few posts as a statistical tentative to "convince" said crackpot that the world is not going crazy (but maybe he is) If I read correctly (using my non-existent Italian, and heavily relying on my tiny bit of Spanish and a lot of google translate), it appears that you are what I would call a high-school math/science teacher, who takes students to competitions? right -- almost! i don't take them to competitions (i am not an official trainer) but sometimes give some general advice to students who would be inclined to compete, if they ask me. bye -- http://mail.python.org/mailman/listinfo/python-list
Re: off topic but please forgive me me and answer
rantingrick ha scritto: On Apr 1, 3:44 pm, superpollo wrote: how much is one half times one half? This is amazing, how can such an off topic post based completely on lunacy exist so long here? 54 posts and counting. I think i had this very argument in grade school. We have SD'A, Tim Chase, MSRB, and yes even Steve Holden again participating in the troll fest (even though some of their arguments are true). Of course i would expect mensenator to jump into this, but... A while back i had wondered why Guido never posts to c.l.py anymore. Was it because he thinks himself better than us, no, it's because of the "low-brow-infantile-Jerry-Springer-ish-nature" that this list has imploded into. *puke* relax mate. -- http://mail.python.org/mailman/listinfo/python-list
Re: pythonrag
Jason Friedman ha scritto: I saw this posted in the July issue but did not see any follow-up there: $ python Python 2.6.4 (r264:75706, Dec 7 2009, 18:43:55) [GCC 4.4.1] on linux2 Type "help", "copyright", "credits" or "license" for more information. a = 500 b = 500 a == b True a is b False p = 50 q = 50 p == q True p is q True LOL -- http://mail.python.org/mailman/listinfo/python-list
Re: Recommend Commercial graphing library
Grant Edwards ha scritto: On 2010-04-06, Grant Edwards wrote: On 2010-04-06, Jean-Michel Pichavant wrote: Pablo Recio Quijano wrote: Why must be commercial, when there is open and free alternatives? Like GNU Plot. Gnuplot is ugly. I'm using it because I don't care if it's ugly but it clearly lacks of look & feel for presentations, as requested by the OP. ^^ In other words, Gnuplot presents information in a clear, obfuscated That should be: unobsuscated stupid spell-checker... Seriously, most of the graphs I've seen in "presentations" would make Ed Tufte spin in his grave. didn't know he died. -- http://mail.python.org/mailman/listinfo/python-list
Re: Python script error when using print
Robbie ha scritto: Hi all, So, I'm trying to use Python with an apache2 server to create some web pages. The web server is configured and seems to work correctly, but only with a certain type of script. For instance, this script works fine #!/usr/bin/env python def index(): s = "Hello World" return s But, a script like this, does not. #!/usr/bin/env python print "hello world" When I try to use the script with print, the server returns a broken link error. There is nothing in the apache error log to help me understand why it won't work. Any help? looks like some cgi issue to me... -- http://mail.python.org/mailman/listinfo/python-list
Re: Teaching Programming
Samuel Williams ha scritto: I personally like indentation. I just wonder whether it is an issue that some people will dislike. i think there is an issue if you -- say -- produce python code, from within another programming environment, to be executed on the fly, at least in some instances. there might be problems if for example you generate code from a one-line template. i use a special template system for my job, which goes like this: ... %%SCHEMA: ... $A, $B, $C being "loop" control variables reserved to the template system. upon parsing, the system generates the corresponding code (say "print 12*2**3") and stores the output for further use. due to design restrictions, i cannot write a code-template which spans multiple template-lines, and that is a problem with python, because for instance i cannot use conditionals or for loops. if it was C or java there wuold be no problem since the source is free-form, so an entire program can "live" on a single source line. bye -- http://mail.python.org/mailman/listinfo/python-list
Re: Teaching Programming
Stefan Behnel ha scritto: superpollo, 04.05.2010 12:28: i think there is an issue if you -- say -- produce python code, from within another programming environment, to be executed on the fly, at least in some instances. there might be problems if for example you generate code from a one-line template. There are a couple of code generation tools available that you can find on PyPI. However, the main reason why this problem doesn't hurt much in Python is that Python is a dynamic language that can get you extremely far without generating code. It's simply not necessary in most cases, so people don't run into problems with it. Stefan Python 2.5.4 (r254:67916, Feb 17 2009, 20:16:45) [GCC 4.3.3] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> A,B=2,3 >>> if A>B: ... print A+B ... else: ... print A**B-B**2 ... -1 >>> A,B=3,2 >>> if A>B: ... print A+B ... else: ... print A**B-B**2 ... 5 >>> tell me please: how can generate the same output (depending on A and B) without control structure? i mean in a natural "pythonic" way... bye -- http://mail.python.org/mailman/listinfo/python-list
Re: Teaching Programming
Stefan Behnel ha scritto: superpollo, 04.05.2010 13:23: Stefan Behnel ha scritto: the main reason why this problem doesn't hurt much in Python is that Python is a dynamic language that can get you extremely far without generating code. It's simply not necessary in most cases, so people don't run into problems with it. Python 2.5.4 (r254:67916, Feb 17 2009, 20:16:45) [GCC 4.3.3] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> A,B=2,3 >>> if A>B: ... print A+B ... else: ... print A**B-B**2 ... -1 >>> A,B=3,2 >>> if A>B: ... print A+B ... else: ... print A**B-B**2 ... 5 tell me please: how can generate the same output (depending on A and B) without control structure? i mean in a natural "pythonic" way... The question is: why do you have to generate the above code in the first place? Isn't a function enough that does the above? of course! *but* if i must generate on-the-fly python code that defines a function i am back again to the problem: def fun(): ecc... how can i put *that* on a oneliner? -- http://mail.python.org/mailman/listinfo/python-list
Re: Teaching Programming
Martin P. Hellwig ha scritto: On 05/04/10 11:28, superpollo wrote: Samuel Williams ha scritto: I personally like indentation. I just wonder whether it is an issue that some people will dislike. there might be problems if for example you generate code from a one-line template. Well a one-line template code generator are great and such, but if the output should be human readable it is necessary to have at least some form of mark-up control on it. Like newlines and indentations. or latex markup, in my case... On the other hand if it is only meant to generate executable code, generating an interpreted code might not be the best solution for the actual problem. yes, maybe generating code for a *compiler* might be faster but you must consider overhead due to compilation time, especially if code snippets are sprinkled by the dozen all over the template file. For the corner cases (I can think of a couple) it is good to know you can use ';' most of the time. most but not always as i noted (think about loops or function definition) bye -- http://mail.python.org/mailman/listinfo/python-list
Re: Teaching Programming
James Mills ha scritto: On Tue, May 4, 2010 at 9:56 PM, superpollo wrote: of course! *but* if i must generate on-the-fly python code that defines a function i am back again to the problem: One-liner: $ python Python 2.6.5 (r265:79063, Apr 27 2010, 18:26:49) [GCC 4.4.1 (CRUX)] on linux2 Type "help", "copyright", "credits" or "license" for more information. a, b = 2, 3 print a + b if a > b else a**b - b**2 -1 a, b = 3, 2 print a + b if a > b else a**b - b**2 5 --James much obliged. -- http://mail.python.org/mailman/listinfo/python-list
Re: Teaching Programming
Stefan Behnel ha scritto: superpollo, 04.05.2010 13:56: Stefan Behnel ha scritto: The question is: why do you have to generate the above code in the first place? Isn't a function enough that does the above? of course! *but* if i must generate on-the-fly python code that defines a function [...] Well, could you provide a use case where you have to generate Python code, and where normally written code with some kind of parametrisation won't work? i see your point, and mr mills gave me hints as to how to attack some of my problems in such a fashion. The only thing that currently comes to my mind is a template compiler that translates a user provided template into an executable Python program. But that should be pretty trivial to do as well. I just remembered this little thing on Fredrik's effbot site, which should help here: http://effbot.org/zone/python-code-generator.htm very good. i will most certainly give it a try. but i do not think i can use it myself, since my template system wants the input to generate the code to stay on a single line ( don't ask :-( ) bye -- http://mail.python.org/mailman/listinfo/python-list
Re: Teaching Programming
Stefan Behnel ha scritto: superpollo, 04.05.2010 14:46: my template system wants the input to generate the code to stay on a single line ( don't ask :-( ) I hope you don't mind if I still ask. What are you generating and for what templating system? ok, since you asked for it, prepare yourself for a bit of a horror story ;-) i will answer in my next post bye -- http://mail.python.org/mailman/listinfo/python-list
Re: Teaching Programming
superpollo ha scritto:
Stefan Behnel ha scritto:
superpollo, 04.05.2010 14:46:
my template system wants
the input to generate the code to stay on a single line ( don't ask
:-( )
I hope you don't mind if I still ask. What are you generating and for
what templating system?
ok, since you asked for it, prepare yourself for a bit of a horror story
;-)
i will answer in my next post
ok here it is.
i am not a programmer or it-guy in the first place; my job is as a high
school teacher in a field only remotely connected with computers (math
and physics).
since i have some kind of computer literacy (as opposed to most of my
colleagues), some years ago i was kindly asked to try and solve a
"simple" particular problem, that is to write a program that generates
math exercises (q+a) from an example taken from the textbook. for
instance, this:
%%TITLE:Sample worksheet
%%
%%SCHEMA:\lim_{x \to }
%%SCHEMA:\frac
%%SCHEMA:{x^3-x^2-x}
%%SCHEMA:{x^3-x^2+x-}\\
%%
%%ANS:FRAC
%%ANSNUM:
%%ANSDEN:
%%
%%AMIN:1
%%AINC:1
%%AMAX:2
%%BMIN:3
%%BINC:1
%%BMAX:4
%%CMIN:2
%%CINC:1
%%CMAX:3
should generate this latex source document:
\documentclass[a4paper,10pt,twocolumn,fleqn]{article}
\title{Sample worksheet}
\pagestyle{empty}
\usepackage[italian]{babel}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{cancel}
\usepackage{mathrsfs}
\usepackage[dvips]{graphicx}
\usepackage{eurosym}
\usepackage{pstricks}
\usepackage{pst-eucl}
\usepackage{pst-poly}
\usepackage{pst-plot}
\frenchspacing
\begin{document}
\section*{\center{\framebox{Sample worksheet}}}
\noindent
\begin{enumerate}
\item
\begin{multline*}
\lim_{x \to 1}
\frac
{x^3+3x^2-4x}
{x^3-x^2+2x-2}\\
\end{multline*}
\item
\begin{multline*}
\lim_{x \to 2}
\frac
{x^3+x^2-6x}
{x^3-2x^2+2x-4}\\
\end{multline*}
\item
\begin{multline*}
\lim_{x \to 2}
\frac
{x^3+2x^2-8x}
{x^3-2x^2+2x-4}\\
\end{multline*}
\item
\begin{multline*}
\lim_{x \to 1}
\frac
{x^3+2x^2-3x}
{x^3-x^2+2x-2}\\
\end{multline*}
\item
\begin{multline*}
\lim_{x \to 1}
\frac
{x^3+2x^2-3x}
{x^3-x^2+3x-3}\\
\end{multline*}
\item
\begin{multline*}
\lim_{x \to 1}
\frac
{x^3+3x^2-4x}
{x^3-x^2+3x-3}\\
\end{multline*}
\item
\begin{multline*}
\lim_{x \to 2}
\frac
{x^3+x^2-6x}
{x^3-2x^2+3x-6}\\
\end{multline*}
\item
\begin{multline*}
\lim_{x \to 2}
\frac
{x^3+2x^2-8x}
{x^3-2x^2+3x-6}\\
\end{multline*}
\end{enumerate}
\subsection*{\center{Answers}}
\begin{enumerate}
\item
\begin{displaymath}
\frac{5}{3}
\end{displaymath}
\item
\begin{displaymath}
\frac{5}{3}
\end{displaymath}
\item
\begin{displaymath}
2
\end{displaymath}
\item
\begin{displaymath}
\frac{4}{3}
\end{displaymath}
\item
\begin{displaymath}
1
\end{displaymath}
\item
\begin{displaymath}
\frac{5}{4}
\end{displaymath}
\item
\begin{displaymath}
\frac{10}{7}
\end{displaymath}
\item
\begin{displaymath}
\frac{12}{7}
\end{displaymath}
\end{enumerate}
\end{document}
which in turn can be used to generate the following pdf file:
http://www.datafilehost.com/download-cc88a19e.html
fine huh? now, for the horror part.
when i began putting down some code i thought that maybe it would take a
couple of evenings to put up a working prototype, and i was w-r-o-n-g:
1) as i said i am not a professional
2) i decided to use bash shell as a core language for the
parser/generator ( *sigh* )
3) feautiritis soon crept in
if some of you knows a bit about math and especially algebra, you will
understand that some of the biggest problems in generating standard math
notation in to cope with the various layers of traditions and innuendos:
for example i could generate the string "2x" which is fine; but what
about "1x" or "-1x" or "0x"? and what about plus signs at the start of
an expression (normally omitted)? when does a subexpression start? etc
... there are plenty of icompatible rules and as much as exceptions ...
as you can see i had many problems to solve and i am not trained to cope
with such issues from a programmatic standpoint.
another thing is that for some features i intended to include i found
convenient to use python (since it's the language i feel i am more at
ease with), so i had to cope with template lines like this:
%%SCHEMA:
or even worse:
%%ANSFRCEMBPYC:"~longmapsto~" , $C**2*(3*$A+3*$B+$C) , "~mathrm{(max~loc.)}">\\
to make a long story short: the whole program is now 4775 lines of bash
code, written by an unqualified amateur under time pressure; sometimes i
have to hand-modify it to get certain outputs as i expect them to be;
this in turn breaks other subsystems.
i am ashamed to post the code, and it is a true design nightmare. also
it is offtopic (being bash).
*but* it was and it is a wonderful experience to learn to program, to
acknowledge weaknesses end strongnesses of various approaches, to better
understand the structure of math notation, problem solving end teaching
techniques.
it is still work in progress though, and i h
Re: Teaching Programming
James Mills ha scritto: On Tue, May 4, 2010 at 9:56 PM, superpollo wrote: of course! *but* if i must generate on-the-fly python code that defines a function i am back again to the problem: One-liner: $ python Python 2.6.5 (r265:79063, Apr 27 2010, 18:26:49) [GCC 4.4.1 (CRUX)] on linux2 Type "help", "copyright", "credits" or "license" for more information. a, b = 2, 3 print a + b if a > b else a**b - b**2 -1 a, b = 3, 2 print a + b if a > b else a**b - b**2 5 --James what if i want an elif clause? -- http://mail.python.org/mailman/listinfo/python-list
Re: Teaching Programming
superpollo ha scritto: James Mills ha scritto: On Tue, May 4, 2010 at 9:56 PM, superpollo wrote: of course! *but* if i must generate on-the-fly python code that defines a function i am back again to the problem: One-liner: $ python Python 2.6.5 (r265:79063, Apr 27 2010, 18:26:49) [GCC 4.4.1 (CRUX)] on linux2 Type "help", "copyright", "credits" or "license" for more information. a, b = 2, 3 print a + b if a > b else a**b - b**2 -1 a, b = 3, 2 print a + b if a > b else a**b - b**2 5 --James what if i want an elif clause? my first try obviously falied: >>> print a + b if a > b elif a=b "WOW" else a**b - b**2 File "", line 1 print a + b if a > b elif a=b "WOW" else a**b - b**2 ^ SyntaxError: invalid syntax -- http://mail.python.org/mailman/listinfo/python-list
Re: Teaching Programming
superpollo ha scritto: superpollo ha scritto: James Mills ha scritto: On Tue, May 4, 2010 at 9:56 PM, superpollo wrote: of course! *but* if i must generate on-the-fly python code that defines a function i am back again to the problem: One-liner: $ python Python 2.6.5 (r265:79063, Apr 27 2010, 18:26:49) [GCC 4.4.1 (CRUX)] on linux2 Type "help", "copyright", "credits" or "license" for more information. a, b = 2, 3 print a + b if a > b else a**b - b**2 -1 a, b = 3, 2 print a + b if a > b else a**b - b**2 5 --James what if i want an elif clause? my first try obviously falied: >>> print a + b if a > b elif a=b "WOW" else a**b - b**2 File "", line 1 print a + b if a > b elif a=b "WOW" else a**b - b**2 ^ SyntaxError: invalid syntax ok i got it: >>> a,b=2,3 >>> print a + b if a > b else "WOW" if a < b else a**b - b**2 WOW >>> -- http://mail.python.org/mailman/listinfo/python-list
Re: Teaching Programming
Martin P. Hellwig ha scritto:
On 05/04/10 12:59, superpollo wrote:
Martin P. Hellwig ha scritto:
For the corner cases (I can think of a couple) it is good to know you
can use ';' most of the time.
most but not always as i noted (think about loops or function definition)
Well through in some exec magic then, for example:
for number in [1,2,3,4]:
def nprint(number):
print(number)
number += 1
nprint(number
translates to:
>>> exec('for number in [1,2,3,4]:\n\tdef
nprint(number):\n\t\tprint(number)\n\tnumber += 1\n\tnprint(number)')
2
3
4
5
But if you have an example why indentation is still a problem please
give it :-)
i think your exec example solved most of my problems. thanks a lot.
bye
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Re: Kindly show me a better way to do it
Oltmans ha scritto: Hi, I've a list that looks like following a = [ [1,2,3,4], [5,6,7,8] ] Currently, I'm iterating through it like for i in [k for k in a]: for a in i: i think you used te a identifier for two meanings... print a but I was wondering if there is a shorter, more elegant way to do it? add = lambda a,b: a+b for i in reduce(add,a): print i -- http://mail.python.org/mailman/listinfo/python-list
Re: Kindly show me a better way to do it
superpollo ha scritto: Oltmans ha scritto: Hi, I've a list that looks like following a = [ [1,2,3,4], [5,6,7,8] ] Currently, I'm iterating through it like for i in [k for k in a]: for a in i: i think you used te a identifier for two meanings... print a but I was wondering if there is a shorter, more elegant way to do it? add = lambda a,b: a+b or: from operator import add for i in reduce(add,a): print i -- http://mail.python.org/mailman/listinfo/python-list
Re: Kindly show me a better way to do it
Oltmans ha scritto: On May 9, 1:53 am, superpollo wrote: add = lambda a,b: a+b for i in reduce(add,a): print i This is very neat. Thank you. Sounds like magic to me. Can you please explain how does that work? Many thanks again. here: http://tinyurl.com/3xp and here: http://tinyurl.com/39kdge5 bye -- http://mail.python.org/mailman/listinfo/python-list
solve a newspaper quiz
"if a b c are digits, solve ab:c=a*c+b" solved in one minute with no thought: for a in range(10): for b in range(10): for c in range(10): try: if (10.*a+b)/c==a*c+b: print "%i%i:%i=%i*%i+%i" % (a,b,c,a,c,b) except: pass any suggestion for improvement? bye -- http://mail.python.org/mailman/listinfo/python-list
Re: Extract all words that begin with x
Jimbo ha scritto:
Hello
I am trying to find if there is a string OR list function that will
search a list of strings for all the strings that start with 'a' &
return a new list containing all the strings that started with 'a'.
I have had a search of Python site & I could not find what I am
looking for, does a function like this exist?
>>> sw = lambda s: lambda t: t.startswith(s)
>>> list = ["a string","another one","this is a string","and so is this
one"]
>>> filter(sw("a"),list)
['a string', 'another one', 'and so is this one']
>>>
bye
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Re: Extract all words that begin with x
superpollo ha scritto:
Jimbo ha scritto:
Hello
I am trying to find if there is a string OR list function that will
search a list of strings for all the strings that start with 'a' &
return a new list containing all the strings that started with 'a'.
I have had a search of Python site & I could not find what I am
looking for, does a function like this exist?
>>> sw = lambda s: lambda t: t.startswith(s)
>>> list = ["a string","another one","this is a string","and so is this
one"]
>>> filter(sw("a"),list)
['a string', 'another one', 'and so is this one']
>>>
bye
of course there is a simpler way:
>>> [string for string in list if string.startswith("a")]
['a string', 'another one', 'and so is this one']
>>>
bye
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Re: Extract all words that begin with x
Aahz ha scritto: In article , Terry Reedy wrote: On 5/10/2010 5:35 AM, James Mills wrote: On Mon, May 10, 2010 at 6:50 PM, Xavier Ho wrote: Have I missed something, or wouldn't this work just as well: list_of_strings = ['2', 'awes', '3465sdg', 'dbsdf', 'asdgas'] [word for word in list_of_strings if word[0] == 'a'] ['awes', 'asdgas'] I would do this for completeness (just in case): [word for word in list_of_strings if word and word[0] == 'a'] Just guards against empty strings which may or may not be in the list. ... word[0:1] does the same thing. All Python programmers should learn to use slicing to extract a char from a string that might be empty. The method call of .startswith() will be slower, I am sure. And if it is slower, so what? Using startswith() makes for faster reading of the code for me, and I'm sure I'm not the only one. also, what if the OP intended "words that begin with x" with x a string (as opposed to a single character) ? then startswith is the solution methinks... bye -- http://mail.python.org/mailman/listinfo/python-list
Re: Slice last char from string without raising exception on empty string (Re: Extract all words that begin with x)
pyt...@bdurham.com ha scritto: Terry, ... word[0:1] does the same thing. All Python programmers should learn to use slicing to extract a char from a string that might be empty. Is there an equivalent way to slice the last char from a string (similar to an .endswith) that doesn't raise an exception when a string is empty? could it be: word[len(word)-1:] ? -- http://mail.python.org/mailman/listinfo/python-list
Re: Iterating over dict and removing some elements
Ulrich Eckhardt ha scritto:
Hi!
I wrote a simple loop like this:
d = {}
...
for k in d:
if some_condition(d[k]):
d.pop(k)
If I run this, Python complains that the dictionary size changed during
iteration. I understand that the iterator relies on the internal structure
not changing, but how would I structure this loop otherwise?
my first thought (untested):
use a copy of d for the if clause, then pop from the original.
bye
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Re: Iterating over dict and removing some elements
superpollo ha scritto:
Ulrich Eckhardt ha scritto:
Hi!
I wrote a simple loop like this:
d = {}
...
for k in d:
if some_condition(d[k]):
d.pop(k)
If I run this, Python complains that the dictionary size changed during
iteration. I understand that the iterator relies on the internal
structure
not changing, but how would I structure this loop otherwise?
my first thought (untested):
use a copy of d for the if clause, then pop from the original.
bye
i mean:
>>> d = {"name":"max","surname":"zanardi","nick":"zanna"}
>>> dc = copy.copy(d)
>>> dc
{'nick': 'zanna', 'surname': 'zanardi', 'name': 'max'}
>>> for k in dc:
... if dc[k].startswith("z"):
... d.pop(k)
...
'zanna'
'zanardi'
>>> d
{'name': 'max'}
>>> dc
{'nick': 'zanna', 'surname': 'zanardi', 'name': 'max'}
>>>
bye
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Re: Slice last char from string without raising exception on empty string (Re: Extract all words that begin with x)
James Mills ha scritto: On Wed, May 12, 2010 at 2:01 AM, wrote: word[len(word)-1:] This works just as well: word[-1:] d'uh. ;-) -- http://mail.python.org/mailman/listinfo/python-list
Re: Extract all words that begin with x
Stefan Behnel ha scritto: superpollo, 11.05.2010 17:03: Aahz ha scritto: In article , Terry Reedy wrote: On 5/10/2010 5:35 AM, James Mills wrote: On Mon, May 10, 2010 at 6:50 PM, Xavier Ho wrote: Have I missed something, or wouldn't this work just as well: list_of_strings = ['2', 'awes', '3465sdg', 'dbsdf', 'asdgas'] [word for word in list_of_strings if word[0] == 'a'] ['awes', 'asdgas'] I would do this for completeness (just in case): [word for word in list_of_strings if word and word[0] == 'a'] Just guards against empty strings which may or may not be in the list. ... word[0:1] does the same thing. All Python programmers should learn to use slicing to extract a char from a string that might be empty. The method call of .startswith() will be slower, I am sure. And if it is slower, so what? Using startswith() makes for faster reading of the code for me, and I'm sure I'm not the only one. also, what if the OP intended "words that begin with x" with x a string (as opposed to a single character) ? word[:len(x)] == x will work in that case. yes ... thanks. -- http://mail.python.org/mailman/listinfo/python-list
Re: Data store solution need help
Haulyn Jason ha scritto: Hi, all: I am a Java programmer, now I am working on a Python program. At the moment, I need to store some data from user's input, no database, no xml, no txt(we can not make users open the data file by vim or other text editor). security thru obscurity? mmmhhh... -- http://mail.python.org/mailman/listinfo/python-list
Re: Human word reader
timo verbeek ha scritto:
I'm planning to create a human word program
A human inputs a string
"Give me the weather for London please."
Then I will strip the string.
"weather for london"
Then I get the useful information.
what:"weather" where:"london"
After that I use the info.
I need help with getting the useful information how do I get the place
if I don't now how long the string is?
>>> query = "Give me the weather for London please."
>>> what = query.strip("Give me the ").split()[0]
>>> where = query.strip("Give me the " + what + " for ").split()[0]
>>> print what, where
weather London
>>>
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Re: Human word reader
superpollo ha scritto:
timo verbeek ha scritto:
I'm planning to create a human word program
A human inputs a string
"Give me the weather for London please."
Then I will strip the string.
"weather for london"
Then I get the useful information.
what:"weather" where:"london"
After that I use the info.
I need help with getting the useful information how do I get the place
if I don't now how long the string is?
>>> query = "Give me the weather for London please."
>>> what = query.strip("Give me the ").split()[0]
>>> where = query.strip("Give me the " + what + " for ").split()[0]
>>> print what, where
weather London
>>>
maybe better not with strip, fot it might not do what i intended (see
docs); maybe preferable to use "partition" method:
>>> query = "Give me the weather for London please."
>>> what = query.partition("Give me the ")[2].split()[0]
>>> where = query.partition(" for ")[2].split()[0]
>>> print what, where
weather London
>>>
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Re: parsing XML
kak...@gmail.com ha scritto: Hi to all, let's say we have the following Xml 17.1 6.4 15.5 7.8 How can i get the players name, age and height? DOM or SAX and how Thanks Antonis another minimal xml.etree.ElementTree solution: >>> print document 17.1 6.4 15.5 7.8 >>> import xml.etree.ElementTree as ET >>> team = ET.XML(document) >>> for player in team: ... print player.attrib["name"] ... print player.attrib["age"] ... print player.attrib["height"] ... print ... Mick Fowler 27 1.96m Ivan Ivanovic 29 2.04m >>> bye -- http://mail.python.org/mailman/listinfo/python-list
Re: parsing XML
superpollo ha scritto:
kak...@gmail.com ha scritto:
Hi to all, let's say we have the following Xml
17.1
6.4
15.5
7.8
How can i get the players name, age and height?
DOM or SAX and how
Thanks
Antonis
another minimal xml.etree.ElementTree solution:
>>> print document
17.1
6.4
15.5
7.8
>>> import xml.etree.ElementTree as ET
>>> team = ET.XML(document)
>>> for player in team:
... print player.attrib["name"]
... print player.attrib["age"]
... print player.attrib["height"]
... print
...
Mick Fowler
27
1.96m
Ivan Ivanovic
29
2.04m
>>>
bye
or, an alternative xml.dom.minidom solution:
>>> import xml.dom.minidom as MD
>>> team = MD.parseString(document)
>>> players = team.getElementsByTagName("player")
>>> for player in players:
... print player.getAttribute("name")
... print player.getAttribute("age")
... print player.getAttribute("height")
... print
...
Mick Fowler
27
1.96m
Ivan Ivanovic
29
2.04m
>>>
bye
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Re: Updating values in a dictionary
Thomas ha scritto:
Greetings
I am having a darn awful time trying to update a matrix:
row = dict([(x,0) for x in range(3)])
matrix = dict([(x,row) for x in range(-3,4,1)])
matrix[2][1] += 1
matrix[-1][2] += 1
"""
Got: a 1 in all col 1 and 2
{-3: {0: 0, 1: 1, 2: 1},
-2: {0: 0, 1: 1, 2: 1},
-1: {0: 0, 1: 1, 2: 1},
0: {0: 0, 1: 1, 2: 1},
1: {0: 0, 1: 1, 2: 1},
2: {0: 0, 1: 1, 2: 1},
3: {0: 0, 1: 1, 2: 1}}
Expected: a 1 in row 2 col 1 and row -1 col 2
{-3: {0: 0, 1: 0, 2: 0},
-2: {0: 0, 1: 0, 2: 0},
-1: {0: 0, 1: 0, 2: 1},
0: {0: 0, 1: 0, 2: 0},
1: {0: 0, 1: 0, 2: 0},
2: {0: 0, 1: 1, 2: 0},
3: {0: 0, 1: 0, 2: 0}}
"""
I must be doing something wrong. Researched and researched. Nothing
clicks.
clone the row:
>>> row = dict([(x,0) for x in range(3)])
>>> import copy
>>> matrix = dict([(x,copy.copy(row)) for x in range(-3,4,1)])
>>> matrix[2][1] += 1
>>> matrix[-1][2] += 1
>>> import pprint
>>> pp = pprint.PrettyPrinter()
>>> pp.pprint(matrix)
{-3: {0: 0, 1: 0, 2: 0},
-2: {0: 0, 1: 0, 2: 0},
-1: {0: 0, 1: 0, 2: 1},
0: {0: 0, 1: 0, 2: 0},
1: {0: 0, 1: 0, 2: 0},
2: {0: 0, 1: 1, 2: 0},
3: {0: 0, 1: 0, 2: 0}}
>>>
bye
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Re: reading XML file using python
Simon Brunning ha scritto: On 17 May 2010 09:34:51 UTC+1, shanti bhushan wrote: Hi , i am new to python.i want to read the XML file using python it ,by using DOm or SAX any of them. I want to read the http://www.google.com(any hyper text) from XML and print that. please give me the sample program for this. Your question isn't very clear. Do you want to read the data from a URL (such as http://www.google.com) and parse it? If so, you probably don't want an XML parser as such - try Beautiful Soup. btw, is there any chance that bs will be part of the stdlib anytime soon? bye -- http://mail.python.org/mailman/listinfo/python-list
recall function definition from shell
>>> def myfun(): ... return "WOW" ... >>> myfun() 'WOW' >>> now, i would like to "list" the funcion definition, something like this: >>> myfun.somethinglikethis() def myfun(): return "WOW" >>> is there something like this around? bye -- http://mail.python.org/mailman/listinfo/python-list
Re: recall function definition from shell
Patrick Maupin ha scritto: On May 18, 12:31 pm, superpollo wrote: >>> def myfun(): ... return "WOW" ... >>> myfun() 'WOW' >>> now, i would like to "list" the funcion definition, something like this: >>> myfun.somethinglikethis() def myfun(): return "WOW" >>> is there something like this around? bye Sure, just give it a docstring and then you can call help on it: def myfun(): ... ''' myfun returns "WOW" when called. ... This is just a Python __doc__ string ... ''' ... return "WOW" ... help(myfun) Regards, Pat mmm... thanks but not quite what i meant :-( bye -- http://mail.python.org/mailman/listinfo/python-list
Re: recall function definition from shell
Patrick Maupin ha scritto: On May 18, 1:41 pm, superpollo wrote: Patrick Maupin ha scritto: On May 18, 12:31 pm, superpollo wrote: >>> def myfun(): ... return "WOW" ... >>> myfun() 'WOW' now, i would like to "list" the funcion definition, something like this: >>> myfun.somethinglikethis() def myfun(): return "WOW" is there something like this around? bye Sure, just give it a docstring and then you can call help on it: def myfun(): ... ''' myfun returns "WOW" when called. ... This is just a Python __doc__ string ... ''' ... return "WOW" ... help(myfun) Regards, Pat mmm... thanks but not quite what i meant :-( bye Well, I don't think Python remembers exactly how you typed it in yes python does not, but maybe the *shell* does, or so i thought. i just wanted to dump the code for the function in a file, after i tested in the shell... -- http://mail.python.org/mailman/listinfo/python-list
Re: recall function definition from shell
Peter Otten ha scritto: superpollo wrote: Patrick Maupin ha scritto: On May 18, 1:41 pm, superpollo wrote: Patrick Maupin ha scritto: On May 18, 12:31 pm, superpollo wrote: >>> def myfun(): ... return "WOW" ... >>> myfun() 'WOW' now, i would like to "list" the funcion definition, something like this: >>> myfun.somethinglikethis() def myfun(): return "WOW" is there something like this around? bye Sure, just give it a docstring and then you can call help on it: def myfun(): ... ''' myfun returns "WOW" when called. ... This is just a Python __doc__ string ... ''' ... return "WOW" ... help(myfun) Regards, Pat mmm... thanks but not quite what i meant :-( bye Well, I don't think Python remembers exactly how you typed it in yes python does not, but maybe the *shell* does, or so i thought. i just wanted to dump the code for the function in a file, after i tested in the shell... You could try ipython: $ ipython Python 2.6.4 (r264:75706, Dec 7 2009, 18:43:55) Type "copyright", "credits" or "license" for more information. IPython 0.10 -- An enhanced Interactive Python. ? -> Introduction and overview of IPython's features. %quickref -> Quick reference. help -> Python's own help system. object? -> Details about 'object'. ?object also works, ?? prints more. In [1]: def f(): ...: return 42 ...: In [2]: f() Out[2]: 42 In [3]: %save tmp.py 1 The following commands were written to file `tmp.py`: def f(): return 42 In [4]: Do you really want to exit ([y]/n)? $ cat tmp.py def f(): return 42 $ Peter hey great! thanks a lot! best regards -- http://mail.python.org/mailman/listinfo/python-list
Re: remove elements incrementally from a list
Javier Montoya ha scritto:
Dear all,
I've a list of float numbers and I would like to delete incrementally
a set of elements in a given range of indexes, sth. like:
for j in range(beginIndex, endIndex+1):
print ("remove [%d] => val: %g" % (j, myList[j]))
del myList[j]
However, since I'm iterating over the same list, the indexes (range)
are not valid any more for the new list.
Does anybody has some suggestions on how to delete the elements
properly?
clone the list, and then loop over the copy while deleting from the original
bye
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ipython question
In [39]: def f(): : return 42 : In [40]: %psource f No source found for f In [41]: i expected to see the source... -- http://mail.python.org/mailman/listinfo/python-list
function that counts...
... how many positive integers less than n have digits that sum up to m: In [197]: def prttn(m, n): tot = 0 for i in range(n): s = str(i) sum = 0 for j in range(len(s)): sum += int(s[j]) if sum == m: tot += 1 return tot .: In [207]: prttn(25, 1) Out[207]: 348 any suggestion for pythonizin' it? bye -- http://mail.python.org/mailman/listinfo/python-list
Re: ipython question
Robert Kern ha scritto: On 5/19/10 12:11 PM, superpollo wrote: In [39]: def f(): : return 42 : In [40]: %psource f No source found for f In [41]: i expected to see the source... You will want to ask IPython questions on the IPython mailing list: http://mail.scipy.org/mailman/listinfo/ipython-user The reason you do not get the source is because there is no file that contains functions defined in the interactive interpreter. %psource uses the inspect module, and the inspect module explicitly only looks in real files but still: In [218]: def f(): .: return 42 .: In [219]: %save tmp.py 218 File `tmp.py` exists. Overwrite (y/[N])? y The following commands were written to file `tmp.py`: def f(): return 42 In [220]: !cat tmp.py def f(): return 42 In [221]: %psource f No source found for f -- http://mail.python.org/mailman/listinfo/python-list
Re: ipython question
superpollo ha scritto: Robert Kern ha scritto: On 5/19/10 12:11 PM, superpollo wrote: In [39]: def f(): : return 42 : In [40]: %psource f No source found for f In [41]: i expected to see the source... You will want to ask IPython questions on the IPython mailing list: http://mail.scipy.org/mailman/listinfo/ipython-user The reason you do not get the source is because there is no file that contains functions defined in the interactive interpreter. %psource uses the inspect module, and the inspect module explicitly only looks in real files but still: In [218]: def f(): .: return 42 .: In [219]: %save tmp.py 218 File `tmp.py` exists. Overwrite (y/[N])? y The following commands were written to file `tmp.py`: def f(): return 42 In [220]: !cat tmp.py def f(): return 42 In [221]: %psource f No source found for f maybe i got it: In [230]: import tmp In [231]: %psource tmp.f def f(): return 42 -- http://mail.python.org/mailman/listinfo/python-list
Re: function that counts...
Jerry Hill ha scritto: On Wed, May 19, 2010 at 3:58 PM, superpollo wrote: ... how many positive integers less than n have digits that sum up to m: ... any suggestion for pythonizin' it? This is how I would do it: def prttn(m, n): """How many positive integers less than n have digits that sum up to m""" total = 0 for testval in range(n): sumofdigits = sum(int(char) for char in str(testval)) this line gives me this: TypeError: 'int' object is not callable is it some new feature in >2.5 ? if sumofdigits == m: total += 1 return total I added a docstring to the function, saying what it does, and what the arguments are supposed to represent. I also moved the convert-to-string-and-sum-the-digits logic into a single generator expression that's passed to the builtin sum function. Oh, and I tried to use slightly more expressive variable names. -- http://mail.python.org/mailman/listinfo/python-list
Re: function that counts...
René 'Necoro' Neumann ha scritto: Am 19.05.2010 21:58, schrieb superpollo: ... how many positive integers less than n have digits that sum up to m: In [197]: def prttn(m, n): tot = 0 for i in range(n): s = str(i) sum = 0 for j in range(len(s)): sum += int(s[j]) if sum == m: tot += 1 return tot .: In [207]: prttn(25, 1) Out[207]: 348 any suggestion for pythonizin' it? bye An idea would be: def prttn(m, n): ... return sum(1 for x in range(n) if sum(map(int, str(x))) == m) TypeError: 'int' object is not callable on 2.5.4 A small oneliner :) (I first had "return len([x for x in ...])" but the above avoids creating an intermediate list) - René -- http://mail.python.org/mailman/listinfo/python-list
Re: function that counts...
Jerry Hill ha scritto: On Wed, May 19, 2010 at 4:25 PM, superpollo wrote: Jerry Hill ha scritto: sumofdigits = sum(int(char) for char in str(testval)) this line gives me this: TypeError: 'int' object is not callable is it some new feature in >2.5 ? No, sum() has been a builtin since Python 2.3. Based on your first post, you have probably shadowed the builtin "sum" function by assigning an integer to a variable named "sum". o my... thanks! In [266]: del(sum) In [267]: def prttn2(m, n): """How many positive integers less than n have digits that sum up to m""" total = 0 for testval in range(n): sumofdigits = sum(int(char) for char in str(testval)) if sumofdigits == m: total += 1 return total .: In [275]: def prttn3(m, n): return sum(1 for x in range(n) if sum(map(int, str(x))) == m) .: In [277]: prttn(25, 1) Out[277]: 348 In [278]: prttn2(25, 1) Out[278]: 348 In [279]: prttn3(25, 1) Out[279]: 348 ok, bye! -- http://mail.python.org/mailman/listinfo/python-list
Re: function that counts...
Mark Dickinson ha scritto: On May 19, 9:30 pm, superpollo wrote: René 'Necoro' Neumann ha scritto: An idea would be: def prttn(m, n): ...return sum(1 for x in range(n) if sum(map(int, str(x))) == m) TypeError: 'int' object is not callable on 2.5.4 The TypeError is almost certainly because you've created a integer 'sum' variable in your script/interpreter session, hiding the built-in sum function. thx -- http://mail.python.org/mailman/listinfo/python-list
Re: function that counts...
Steven D'Aprano ha scritto: On Wed, 19 May 2010 22:58:22 +0200, superpollo wrote: In [266]: del(sum) del is a statement, not a function, so the brackets are pointless. This is like writing: x = (1) instead of x = 1 `del sum` is all you need. sorry about that, thanks a lot! bye -- http://mail.python.org/mailman/listinfo/python-list
Re: function that counts...
Steven D'Aprano ha scritto: On Wed, 19 May 2010 21:58:04 +0200, superpollo wrote: ... how many positive integers less than n have digits that sum up to m: In [197]: def prttn(m, n): Does the name "prttn" mean anything? I'm afraid I keep reading it as a mispelling of "print n". pArtItIOn [...] s = str(i) sum = 0 for j in range(len(s)): sum += int(s[j]) Rather than iterating over an index j = 0, 1, 2, ... and then fetching the jth character of the string, you can iterate over the characters directly. So the inner loop is better written: for c in s: sum += int(c) d'oh! some day i will learn to speak pythonese! thanks bye -- http://mail.python.org/mailman/listinfo/python-list
Re: function that counts...
Richard Thomas ha scritto:
For this kind of problem you should avoid all that stringification. I
find it best to deal with sequences of digits of a fixed length and go
from there. For example:
def count1(m, n, cache={}):
"""Number of digit sequences of length `n` summing to `m`."""
if n < 0 or m < 0:
return 0
elif n == 0:
return int(m == 0)
elif (m, n) in cache:
return cache[m, n]
# This is an optimisation using the combinatoric choose function.
#elif m < 10:
#result = choose(n + m - 1, n - 1)
else:
result = 0
for digit in xrange(min(10, m + 1)):
result += count1(m - digit, n - 1)
cache[m, n] = result
return result
Notice the caching of results. With this we can compute the required
thing quite easily:
def count2(m, n):
"""Number of numbers less than `n` whose digits sum to `m`."""
result = 0
digits = map(int, str(n))
length = len(digits)
for idx, digit in enumerate(digits):
for seq_digit in xrange(digit):
seq_limit = m - seq_digit
seq_length = length - idx - 1
result += count1(seq_limit, seq_length)
m -= digit
return result
Essentially we move through the number left to right, choose digits
less than the digit in the number and count digit sequences to fill
the remainder. Then fix the actual digit and step forward.
An approach like this avoids the relatively slow stringification
process and makes decent use of caching and iteration (both easy and
efficient in Python).
In [1]: count2(25, 1)
Out[1]: 348
In [2]: timeit count2(25, 1)
10 loops, best of 3: 12.6 us per loop
wow.
impressive, thanks.
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Re: function that counts...
Peter Pearson ha scritto: On Wed, 19 May 2010 21:58:04 +0200, superpollo wrote: ... how many positive integers less than n have digits that sum up to m: If it's important for the function to execute quickly for large n, you might get a useful speedup by testing only every ninth integer, since any two integers whose digits add up to m differ by a multiple of 9. A simple application of this observation would be to test range( m % 9, n, 9 ) rather than testing range( 1, n ). I suspect that further applications of number theory would provide additional, substantial speedups, but this wanders away from the subject of Python. great suggestion, thanks! -- http://mail.python.org/mailman/listinfo/python-list
Re: function that counts...
Grant Edwards ha scritto: On 2010-05-20, superpollo wrote: Steven D'Aprano ha scritto: On Wed, 19 May 2010 21:58:04 +0200, superpollo wrote: ... how many positive integers less than n have digits that sum up to m: In [197]: def prttn(m, n): Does the name "prttn" mean anything? I'm afraid I keep reading it as a mispelling of "print n". pArtItIOn One might be tempted to suggest the name "partition". no kidding: i was afraid to use some reserved word... -- http://mail.python.org/mailman/listinfo/python-list
Re: function that counts...
Jean-Michel Pichavant ha scritto: Jerry Hill wrote: On Wed, May 19, 2010 at 3:58 PM, superpollo wrote: ... how many positive integers less than n have digits that sum up to m: ... any suggestion for pythonizin' it? This is how I would do it: def prttn(m, n): """How many positive integers less than n have digits that sum up to m""" total = 0 for testval in range(n): sumofdigits = sum(int(char) for char in str(testval)) if sumofdigits == m: total += 1 return total I added a docstring to the function, saying what it does, and what the arguments are supposed to represent. I also moved the convert-to-string-and-sum-the-digits logic into a single generator expression that's passed to the builtin sum function. Oh, and I tried to use slightly more expressive variable names. my favorite solutio nso far. @ OP What means prttn ? i already answered this downthreads... something ... I don't find the word, something like un-intuitive. Sounds like homework. it is not. -- http://mail.python.org/mailman/listinfo/python-list
Re: function that counts...
Jean-Michel Pichavant ha scritto: superpollo wrote: Jean-Michel Pichavant ha scritto: Jerry Hill wrote: On Wed, May 19, 2010 at 3:58 PM, superpollo wrote: ... how many positive integers less than n have digits that sum up to m: ... any suggestion for pythonizin' it? This is how I would do it: def prttn(m, n): """How many positive integers less than n have digits that sum up to m""" total = 0 for testval in range(n): sumofdigits = sum(int(char) for char in str(testval)) if sumofdigits == m: total += 1 return total I added a docstring to the function, saying what it does, and what the arguments are supposed to represent. I also moved the convert-to-string-and-sum-the-digits logic into a single generator expression that's passed to the builtin sum function. Oh, and I tried to use slightly more expressive variable names. my favorite solutio nso far. @ OP What means prttn ? i already answered this downthreads... something ... I don't find the word, something like un-intuitive. Sounds like homework. it is not. My apologies then, for both statements. I still don't see "how many positive integers less than n have digits that sum up to m" makes it a "partition" though if that what prttn means. Surely because I miss the context. JM ok, this is the mistery. it was inspired by a question on e.c.m.: http://groups.google.it/group/es.ciencia.matematicas/msg/f8f09672bd8a052a the first question is (somewhat) an instance of: http://en.wikipedia.org/wiki/Partition_(number_theory) bye -- http://mail.python.org/mailman/listinfo/python-list
Re: Creating a single list
Astley Le Jasper ha scritto:
This is probably a really silly question but, given the example code
at the bottom, how would I get a single list?
What I currently get is:
('id', 20, 'integer')
('companyname', 50, 'text')
[('focus', 30, 'text'), ('fiesta', 30, 'text'), ('mondeo', 30,
'text'), ('puma', 30, 'text')]
('contact', 50, 'text')
('email', 50, 'text')
what I would like is:
('id', 20, 'integer')
('companyname', 50, 'text')
('focus', 30, 'text'),
('fiesta', 30, 'text'),
('mondeo', 30, 'text'),
('puma', 30, 'text'),
('contact', 50, 'text')
('email', 50, 'text')
SAMPLE CODE>>>
def getproducts():
temp_list=[]
product_list=['focus','fiesta','mondeo','puma'] #usually this
would come from a db
for p in product_list:
temp_list.append((p,30,'text'))
return temp_list
def createlist():
column_title_list = (
("id",20,"integer"),
("companyname",50,"text"),
getproducts(),
("contact",50,"text"),
("email",50,"text"),
)
return column_title_list
for item in createlist():
print item
>>> def createlist():
... column_title_list = [
... ("id",20,"integer"),
... ("companyname",50,"text")]
... column_title_list += getproducts()
... column_title_list += [
... ("contact",50,"text"),
... ("email",50,"text")]
... return column_title_list
...
>>> for item in createlist():
... print item
...
('id', 20, 'integer')
('companyname', 50, 'text')
('focus', 30, 'text')
('fiesta', 30, 'text')
('mondeo', 30, 'text')
('puma', 30, 'text')
('contact', 50, 'text')
('email', 50, 'text')
>>>
bye
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Re: Reading file bit by bit
Ulrich Eckhardt ha scritto: Peter Otten wrote: Ulrich Eckhardt wrote: Says Python: bin(192) '0x1100' Hmm, if that's what /your/ Python says, here's mine to counter: bin(192) '0_totally_faked_binary_0011' Argh! Of course one of my Pythons says '0b1100' and not what I mistyped above =( mine goes like this: >>> bin(192) Traceback (most recent call last): File "", line 1, in NameError: name 'bin' is not defined -- http://mail.python.org/mailman/listinfo/python-list
Re: GUIs - A Modest Proposal
Andreas Waldenburger ha scritto: On Thu, 10 Jun 2010 23:00:37 -0700 (PDT) rantingrick wrote: On Jun 11, 12:17 am, ant wrote: I like the points about backwards compatibility. Presumably that reason alone is enough to keep Tkinter in the standard library for a long while. I don't see why that is a good reason. Download Tkinter and your backward compatible again. The majority don't use it anyway. I would bet that only myself, Kevin, and only a handful of others use Tkinter for anything more than education purposes. I have a strong suspicion that Tkinter may be used a lot more than is made public (isn't anything?). I'm especially thinking about scientists who write special purpose data processing or control programs with basic GUIs. These things don't have to be pretty or anything and it is a HUGE advantage if you don't have to jump through any hoops to get it to run on different platforms. /W e.g.: http://heim.ifi.uio.no/~hpl/INF5660/PyBasics.pdf bye -- http://mail.python.org/mailman/listinfo/python-list
Re: a +b ?
yanhua ha scritto: hi,all?? it's a simple question: input two integers A and B in a line,output A+B? this is my program: s = input() this does not work t = s.split() a = int(t[0]) b = int(t[1]) print(a+b) but i think it's too complex,can anybody tell to slove it with less code. >>> import operator >>> print reduce(operator.add, map(int, raw_input().split())) 124312 41242 165554 >>> bye -- http://mail.python.org/mailman/listinfo/python-list
Re: a +b ?
Simon Brunning ha scritto:
2010/6/11 yanhua :
hi,all！
it's a simple question:
input two integers A and B in a line,output A+B?
print sum(int(i) for i in raw_input("Please enter some integers: ").split())
LOL
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pythonize this!
goal (from e.c.m.): evaluate 1^2+2^2+3^2-4^2-5^2+6^2+7^2+8^2-9^2-10^2+...-2010^2, where each three consecutive + must be followed by two - (^ meaning ** in this context) my solution: >>> s = 0 >>> for i in range(1, 2011): ... s += i**2 ... if not (i+1)%5: ... s -= 2*i**2 ... if not i%5: ... s -= 2*i**2 ... >>> print s 536926141 >>> bye -- http://mail.python.org/mailman/listinfo/python-list
Re: pythonize this!
Ulrich Eckhardt ha scritto: superpollo wrote: ... s += i**2 ... if not (i+1)%5: ... s -= 2*i**2 ... if not i%5: ... s -= 2*i**2 if not (i % 5) in [1, 2]: s += i**2 else: s -= i**2 Untested code. does not work: >>> s = 0 >>> for i in range(1, 2011): ... if not (i % 5) in [1, 2]: ... s += i**2 ... else: ... s -= i**2 ... >>> print s 546627205 >>> but this does: >>> s = 0 >>> for i in range(1, 2011): ... if i % 5 in [1, 2, 3]: ... s += i**2 ... else: ... s -= i**2 ... >>> print s 536926141 bye -- http://mail.python.org/mailman/listinfo/python-list
Re: pythonize this!
Peter Otten ha scritto: superpollo wrote: goal (from e.c.m.): evaluate 1^2+2^2+3^2-4^2-5^2+6^2+7^2+8^2-9^2-10^2+...-2010^2, where each three consecutive + must be followed by two - (^ meaning ** in this context) from itertools import cycle, izip sum(sign*i*i for sign, i in izip(cycle([1]*3+[-1]*2), range(1, 2011))) 536926141 don't understand it bit i like this a lot! -- http://mail.python.org/mailman/listinfo/python-list
Re: pythonize this!
superpollo ha scritto: Peter Otten ha scritto: superpollo wrote: goal (from e.c.m.): evaluate 1^2+2^2+3^2-4^2-5^2+6^2+7^2+8^2-9^2-10^2+...-2010^2, where each three consecutive + must be followed by two - (^ meaning ** in this context) from itertools import cycle, izip sum(sign*i*i for sign, i in izip(cycle([1]*3+[-1]*2), range(1, 2011))) 536926141 don't understand it bit i like this a lot! ^^^ *but* -- http://mail.python.org/mailman/listinfo/python-list
Re: GUIs - A Modest Proposal
lkcl ha scritto: ... That sounds too good to be true. yup, it does. how can one person, a free software developer, have come up with something like "The Holy Grail" of software development, right? when all the money in the world, from ibm, adobe, microsoft, google, nokia and so on _hasn't_ managed it, in what... 20 years of computer science, right? i must be some sort of egomaniac, attention- seeker, snake-oil-seller or just an outright liar, right? those _are_ supposed to be rhetorical questions :) I sort of have to be reading too much into what you're saying. no, you got it. does what it says on the tin. mind you, i am no python expert, but i really look forward to seeing pyjamas in the stdlib :-) anytime soon? bye -- http://mail.python.org/mailman/listinfo/python-list
Re: pythonize this!
Stefan Behnel ha scritto: superpollo, 15.06.2010 14:55: Peter Otten ha scritto: superpollo wrote: goal (from e.c.m.): evaluate 1^2+2^2+3^2-4^2-5^2+6^2+7^2+8^2-9^2-10^2+...-2010^2, where each three consecutive + must be followed by two - (^ meaning ** in this context) from itertools import cycle, izip sum(sign*i*i for sign, i in izip(cycle([1]*3+[-1]*2), range(1, 2011))) 536926141 don't understand it bit i like this a lot! Didn't you want to get it "pythonized"? If it's not understandable, it can't be pythonic. maybe i must study itertools then ;-) thanks bye -- http://mail.python.org/mailman/listinfo/python-list
Re: pythonize this!
Paul Rubin ha scritto: superpollo writes: goal (from e.c.m.): evaluate 1^2+2^2+3^2-4^2-5^2+6^2+7^2+8^2-9^2-10^2+...-2010^2, where each three consecutive + must be followed by two - (^ meaning ** in this context) print sum([-1,1,1,1,-1][i%5]*i**2 for i in xrange(1,2011)) beautiful. thx -- http://mail.python.org/mailman/listinfo/python-list
python source code -> win/dos executable (on linux)
hi. suppose i work in a linux environment, but i would like to ship a win/dos executable file from time to time, just for test purposes (my "testers" are windows users and don't want to go through the hassle of installing python on their win boxes). what is the best way to do that? (the application should be a simple console app, but my question applies to gui/tkinter apps too) hint: when i do the same in C, i usually do something like: http://www.youtube.com/watch?v=rhe6N7FB1D4 bye -- http://mail.python.org/mailman/listinfo/python-list
Re: python source code -> win/dos executable (on linux)
Lawrence D'Oliveiro ha scritto: In message <4c24c152$0$31381$4fafb...@reader1.news.tin.it>, superpollo wrote: suppose i work in a linux environment, but i would like to ship a win/dos executable file from time to time, just for test purposes (my "testers" are windows users and don't want to go through the hassle of installing python on their win boxes). Is it really such a hassle to install things on Windows? no, but it *IS* to explain it to dumb users... :-( bye -- http://mail.python.org/mailman/listinfo/python-list
Re: automate minesweeper with python
Ethan Furman ha scritto: Terry Reedy wrote: On 7/1/2010 6:42 PM, Emile van Sebille wrote: On 7/1/2010 2:52 PM Jay said... pywinauto looks to be almost perfect. All I need now is to read the numbers uncovered when a minesweeper square is clicked on, or that I just hit a mine. ... or, you could always win... http://www.daniweb.com/forums/thread186209.html Did you actually try it? Though skeptical, I did, briefly, until I decided that it probably should have been dated April 1. There is no way to enter text into minesweeper, nor to make it full screen, nor, as far as I know, for it to toggle pixels outside its window. The pixel can be hard to see depending on your background colors and whether your screen is adjusted correctly (I could see the white, but not the black). But on XP Pro is still works. works for me too bye -- http://mail.python.org/mailman/listinfo/python-list
timer
hi folks. the follwing shoud print 'stuff' for 3 seconds and then stop. why it does not work? (prints stuff forever) 1 #!/usr/bin/python 2 3 import threading 4 import sys 5 6 t = threading.Timer(3.0, sys.exit) 7 t.start() 8 while True: 9 print "stuff ", bye -- http://mail.python.org/mailman/listinfo/python-list
Re: timer
Paul Moore wrote: 2009/6/29 MRAB : superpollo wrote: hi folks. the follwing shoud print 'stuff' for 3 seconds and then stop. why it does not work? (prints stuff forever) 1 #!/usr/bin/python 2 3 import threading 4 import sys 5 6 t = threading.Timer(3.0, sys.exit) 7 t.start() 8 while True: 9 print "stuff ", The Timer runs the function in another thread. Perhaps sys.exit is just exiting that thread and not the main thread. sys.exit raises a SystemExit exception, which will get handled in the new thread (where it won't do anything). Conceded, this isn't particularly intuitive. For a non-toy example, you'd probably create an Event object, use your timer to set the event, and your while loop would do while event.is_set(), so the problem wouldn't arise. thank u paul. if u dont mind, would you give me a more detailed piece of code that does what i mean? tia -- http://mail.python.org/mailman/listinfo/python-list
Re: timer
Paul Moore wrote: 2009/6/29 MRAB : superpollo wrote: hi folks. the follwing shoud print 'stuff' for 3 seconds and then stop. why it does not work? (prints stuff forever) 1 #!/usr/bin/python 2 3 import threading 4 import sys 5 6 t = threading.Timer(3.0, sys.exit) 7 t.start() 8 while True: 9 print "stuff ", The Timer runs the function in another thread. Perhaps sys.exit is just exiting that thread and not the main thread. sys.exit raises a SystemExit exception, which will get handled in the new thread (where it won't do anything). Conceded, this isn't particularly intuitive. For a non-toy example, you'd probably create an Event object, use your timer to set the event, and your while loop would do while event.is_set(), so the problem wouldn't arise. Paul. so why this does not work? 1 #!/usr/bin/python 2 3 import threading 4 5 e = threading.Event() 6 t = threading.Timer(3.0, e.set()) 7 t.start() 8 while not e.isSet(): 9 print "stuff ", it does *NOT* print (but it should, shouldn't it?), then exits after 3 sec but with error: Exception in thread Thread-1:Traceback (most recent call last): File "/usr/lib/python2.3/threading.py", line 442, in __bootstrap self.run() File "/usr/lib/python2.3/threading.py", line 575, in run self.function(*self.args, **self.kwargs) TypeError: 'NoneType' object is not callable what gives? -- http://mail.python.org/mailman/listinfo/python-list
Re: timer
Paul Moore wrote: 2009/6/30 superpollo : Paul Moore wrote: For a non-toy example, you'd probably create an Event object, use your timer to set the event, and your while loop would do while event.is_set(), so the problem wouldn't arise. thank u paul. if u dont mind, would you give me a more detailed piece of code that does what i mean? No problem: import threading e = threading.Event() t = threading.Timer(3.0, e.set) t.start() while not e.is_set(): print "Hello, threading world" Hope this helps, Paul hi while i was waiting 4 ur reply, i posted an almost equal example, but it does not work... -- http://mail.python.org/mailman/listinfo/python-list
Re: timer
Paul Moore wrote: 2009/6/30 superpollo : Paul Moore wrote: For a non-toy example, you'd probably create an Event object, use your timer to set the event, and your while loop would do while event.is_set(), so the problem wouldn't arise. thank u paul. if u dont mind, would you give me a more detailed piece of code that does what i mean? No problem: import threading e = threading.Event() t = threading.Timer(3.0, e.set) t.start() while not e.is_set(): print "Hello, threading world" Hope this helps, Paul do not bother answering... my fault. i wrote e.set() and not e.set thanks again -- http://mail.python.org/mailman/listinfo/python-list
Re: timer
i would like to thank each and everyone for help given, and aplologise for my inaccuracy. thanks 10**3! superchicken -- http://mail.python.org/mailman/listinfo/python-list
stringio+tarfile
why the following does not work? can you help me correct (if possible)?
1 import tarfile
2 import StringIO
3 sf1 = StringIO.StringIO("one\n")
4 sf2 = StringIO.StringIO("two\n")
5 tf = StringIO.StringIO()
6 tar = tarfile.open(tf , "w")
7 for name in [sf1 , sf2]:
8 tar.add(name)
9 print tf
10 sf1.close()
11 sf2.close()
12 tf.close()
13 tar.close()
tia
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Re: stringio+tarfile
First problem I see is all those numbers before the lines. That's not valid python. Assuming that was a transcription error not so. i intentionally add linenumbers to facilitare reference to the code, but if it is a nuisance i will not include them anymore. thanks -- http://mail.python.org/mailman/listinfo/python-list
Re: stringio+tarfile
thanks to the guys who bothered to answer me even using their chrystal
ball ;-)
i'll try to be more specific.
yes: i want to create a tar file in memory, and add some content from a
memory buffer...
my platform:
$ uname -a
Linux fisso 2.4.24 #1 Thu Feb 12 19:49:02 CET 2004 i686 GNU/Linux
$ python -V
Python 2.3.4
following some suggestions i modified the code:
$ cat tar001.py
import tarfile
import StringIO
sfo1 = StringIO.StringIO("one\n")
sfo2 = StringIO.StringIO("two\n")
tfo = StringIO.StringIO()
tar = tarfile.open(fileobj=tfo , mode="w")
ti = tar.gettarinfo(fileobj=tfo)
for sfo in [sfo1 , sfo2]:
tar.addfile(fileobj=sfo , tarinfo=ti)
print tfo
and that's what i get:
$ python tar001.py > tar001.out
Traceback (most recent call last):
File "tar001.py", line 7, in ?
ti = tar.gettarinfo(fileobj=tfo)
File "/usr/lib/python2.3/tarfile.py", line 1060, in gettarinfo
name = fileobj.name
AttributeError: StringIO instance has no attribute 'name'
can you help?
TIA
ps: i'd also like that the tar file has names for the buffers, so than
once output the file can be untarred with /bin/tar into regular files...
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Re: stringio+tarfile
Peter Otten wrote:
gettarinfo() expects a real file, not a file-like object.
You have to create your TarInfo manually.
ok... which attributes are mandatory, and which optional?
I recommend that you have a look into the tarfile module's source code.
i will try... but:
$ cat /usr/lib/python2.3/tarfile.py | wc -l
1938
wow! it'll take some time ;-)
The following seems to work:
import sys
import time
import tarfile
import StringIO
sf1 = "first.txt", StringIO.StringIO("one one\n")
sf2 = "second.txt", StringIO.StringIO("two\n")
tf = StringIO.StringIO()
tar = tarfile.open(fileobj=tf , mode="w")
mtime = time.time()
for name, f in [sf1 , sf2]:
ti = tarfile.TarInfo(name)
ti.size = f.len
ti.mtime = mtime
# add more attributes as needed
tar.addfile(ti, f)
sys.stdout.write(tf.getvalue())
Peter
much obliged mr otten
bye
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Re: stringio+tarfile (or better... zipfile)
following the excellent suggestions received, i tried to adapt the
problem to zipfile, and i wrote this:
$ cat zip001.py
import sys
import zipfile
import StringIO
nb1 = "first.txt", StringIO.StringIO("one one\n")
nb2 = "second.txt", StringIO.StringIO("two\n")
zb = StringIO.StringIO()
zip = zipfile.ZipFile(zb , "w" , zipfile.ZIP_DEFLATED)
for name , buffer in [nb1 , nb2]:
zip.writestr(name, buffer.getvalue()*1000)
zip.close()
sys.stdout.write(zb.getvalue())
$ python zip001.py > zip001.out
$ unzip -l zip001.out
Archive: zip001.out
Length Date TimeName
8000 07-03-09 22:07 first.txt
4000 07-03-09 22:07 second.txt
---
12000 2 files
$
it seems to me thaz zipfile has a simpler usability... any comments?
thanks again and bye bye
--
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older pythons
hi everybody. i have a certain set of old python scripts and data used by said scripts which were written using python 2.3 in particular i used some features which were later modified or deprecated by the language newer versions (e.g.: cmp(), print as keyword, and such...) for reasons i find hard to explain briefly, it is unfeasible at the moment to modify scripts and data to adapt to the changes now: i ask if it is possible to have different versions of python installed on my system (linux debian) so that i can continue to use python 2.3 (as "python" from the shell) but i can also use - say - python 3.1 (maybe as "python3.1" from the shell) if yes: is there a known recommended way to do so? thanks a lot bye -- http://mail.python.org/mailman/listinfo/python-list
Re: older pythons
Adrian Dziubek wrote: The recommended Debian way is update-alternatives. I find it a bit unintuitive, so I have to read through the documentation every time I use it, but it should be able link a chosen version of python to /usr/ bin/python. I don't know if it's set up by default, I have only one version installed. -- Adrian what i was asking for is about a way to *INSTALL* and mantain different python versions, a task i think is not unusal for developers. thanks anyway for reply bye -- http://mail.python.org/mailman/listinfo/python-list
Re: older pythons
Lie Ryan wrote: AFAIK, no major linux distributions have officially ported to python 3.x. http://packages.debian.org/experimental/python3.1 thanks for help -- http://mail.python.org/mailman/listinfo/python-list
