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Comments:
<0> Cope: please don't paste more than 3 lines to the channel.
<1> tirkal: that was three lines
<0> Cope: yup, but not the upper part.
<1> oh right, yeah sorry
<2> robin_2: well, in fact char * _are_ LPCTSTR
<3> innervision: or wchar if the build is UNICODE
<2> robin_2: yeap, and there you have to choose.
<3> innervision: is it some setting in swig so it uses wchar ?
<3> because I can't find it.
<2> robin_2: mhh, as far as I remember (long time since last time I used SWIG) there were some configuration files...
<1> so what I am trying to do is, from a file containing 100s of lines, do a re match, and then pick out fields;
<1> the re match works, as i can print out the correct lines
<1> (with the , after the print)
<1> but my split() fails on intermediate lines, I think
<4> I am writing an application which will divide big numbers and it works rather slow...would it be faster if I write a C module to divide big numbers or is there another way maybe?
<5> hawking: C doesn't have "big numbers", so you would need a big numbers library.
<1> oh maybe I am worng... sorry, I think I've just fat fingered the [20]
<1> :(
<2> hawking: what do you mean by "big numbers"?
<1> *blush*
<4> Erwin I know
<4> innervision numbers more than 500 digits
<6> i'm a fan of the "buy more expensive hardware" solution :)
<4> Erwin I just have to know if that will make it faster or if the builtin divide is already developed with C
<5> "builtin divide" ?
<5> dividing a python long by another long uses C code.
<5> >>> print 13**37/4**42
<5> 8499324282253148
<5> ^^ instant answer
<2> hawking: well, AFAIK all big numbers libraries for C are made in C (or ***embly)
<3> innervision: "At this time, SWIG does not provide any special support for Unicode or wide-character strings (the C wchar_t type). "
<3> from the SWIG docs
<3> ;(
<5> Generally to make things fast in Python you need to spend as little time in Python as possible.
<2> robin_2: ****s to use swig :(
<3> innervision: any alternative ?
<3> ctypes was no success either
<2> robin_2: maybe use ctypes?
<4> Erwin : how exactly would I do that?
<2> robin_2: oh :(
<5> hawking: By programming smartly.
<4> innervision : do you mean big number libs for python?
<4> Erwin : yeah I guess that's the best option
<2> hawking: all of them
<5> hawking: Did you profile your program?
<4> Erwin no
<5> hawking: Then it is rather prematurely to be thinking of rewriting it in C
<4> Erwin : well it's a simple app
<4> just needs to run fast
<7> hawking: 1) profile. 2) redesign your algorithm 3) GNU MP if absolutely necessary
<2> hawking: now I understood, you think that dividing the numbers in C rather than in python will make things faster? well, I don't think it will make such a big difference.
<7> hawking: having no idea what your algorithm is I would suggest you look at divmod. It would be a big difference, if applicable :)
<4> divmod what's that?
<7> err wait, I'm thinking about something else. Nevermind!
<5> divmod(a,b) returns a/b and a%b faster than a/b and a%b
<7> but divmod is a combined divide and modular
<5> But really, you cannot hope for a silver bullet
<5> If you refuse to analyse and profile your algorithm, you have already lost.
<7> For all you know it may be the print that's slow ;)
<4> Erwin : I see .. does it work with long numbers too?
<5> It is very slow to convert large longs to strings.
<4> I know that
<7> int, long, float.. probably others
<1> pattern = re.compile(r"*(*)$")
<5> Cope: Err, that's a nonsensical pattern.
<1> yes
<1> utterly
<1> i was about to explain what it was tryig to do
<1> If I have a line like "some stuff like this example(10)"
<1> I only want the (10)
<1> actually I only want the 10
<5> >>> m = re.search(r"\((\d+)\)", "example(10)"); print m.group(1)
<5> 10
<5> That's ***uming your () can only contain digits.
<1> yeah
<1> that's correct
<5> If you want everything until the first ) you can use .*? there instead, for a non-greedy match everything (i.e. match the least amount possible)
<4> how can i get divmod for python?
<8> At divmod.org?
<5> hawking: The same place you got "abs" for Python.
<4> veracon_ well there are many packages there which one do i need to use divmod to divide numbers faster
<2> Erwin: you get "abs" the same place you get "pecs" and "biceps"?
<8> Oh
<9> hawking: divmod(x, y) is a built-in function in python
<5> hawking: divmod doesn't divide numbers faster. divmod is faster than a division AND a mod.
<10> very cunning innervision
<4> lol sorry
<2> Flibberdy: lol
<5> Really, you are looking for some magic bullet when none exists.
<8> 'from abs import sixpack'? ;P
<4> Erwin : I just need mod actually
<9> veracon_: its early here. oops :P
<8> Hehe.
<11> i think that function could be more general... 'from abs import pack; pack(6)'
<11> or, more realistically, pack(1)
<12> Is it possible to use call C libraries from a python programme? Where can I read about it?
<12> s/use call/call/
<2> tralala: look for ctypes and SWIG
<5> tralala: Or pyrex.
<2> Erwin: had they ever ported Pyrex to windows?
<12> thank you!
<5> innervision: I'm not sure it would require porting. It just generates C code and is written in pure Python.
<2> Erwin: mhh, maybe I'm wrong but last time I checked it didn't work very well with any C compiler under window (not even GCC)
<11> as long as that's being talked about... what is there for embedding python in C?that's a project i'm gonna have to tackle in a couple weeks. i have experience with the direct C API but obviously something a bit more automatic would be nice
<5> mcmillen: You would build a Python module using the above mentioned tools to interface with your code really. That's all.
<5> mcmillen: If you have some C API you want your Python code to access , you must wrap it, whether you embed or extend
<11> i need to embed (for very baroque reasons). from what i see, pyrex won't help me, but swig might?
<5> pyrex will help you just as much as swig
<5> they both let you wrap C APIs for use from Python.
<5> The trick in embedding is to do as much in Python as possible. E.g. setup code, interpreters etc.
<13> COM!
<11> *nods* okay, pyrex's documentation seems more accurate than their "brief description", which led me to believe it couldn't be used for embedding... thanks for pointing it out
<11> and yes, i definitely want to do as much as possible in python
<11> but unfortunately the executable itself has to be C
<5> Why?
<11> the python bit is one component of a proprietary, closed-source distributed message-p***ing framework... think a crippled version of CORBA
<11> and if i don't use the existing (closed-source) tools for developing linux executables that talk to this thing... well, i'd have to reverse-engineer the format of the TCP connections between these executables... which is not really my cup of tea
<14> hi, i am very new to python, just started it. how can i put string with an integer? hwo do i convert an integer to a string??
<5> draxas: What tutorial are you using?
<8> You can use the str and int cl***es
<14> nothign really :)
<8> str(2) = '2'
<14> just started by guessing :)
<8> int('33') = 33
<5> draxas: Start reading one then.
<8> Yeah, good idea.
<14> l;ets say i have somenum = 15 and then i do print "Hello, The ID is " , hwo do i add sumenum there, + doesnt seem to work
<8> print 'Hello, the ID is %s' % somenum
<14> very noobish question, i know :)
<8> That's how I would do it
<14> thanks veracon_
<14> works smooth
<8> Remember, if you're formatting with multiple arguments, you must use a longer sequence (list, tuple -- or dictionary if you use named arguments) but if you're just beginning, let's wait with that. :P
<14> im not new to programming, so far i do pascal, delphi and php ):
<8> If you want a tutorial, I recommend Dive Into Python (diveintopython.org), that's how I started
<2> draxas: what veracon_ means is that if you need to put some more things inside the string you could use "This is an string with (%s) or (%s) arguments" % (arg1, arg2)
<14> ok ill have a look
<14> allright innervision
<8> Yeah
<8> And named arguments could work like this; 'This is a %(what).' % {'what': 'string'}
<8> no
<8> %(what)s*
<14> just one question, is python to be used more on web servers, or for actual software? there are some websites that use python and some python based software..
<8> I find it pretty good for both purposes, personally
<5> Python is a general-purpose high-level programming language
<14> ok :)
<14> i figured out first code in 30 seconds, for c it took fo me to ask in irc
<2> draxas: I have used python to build a GPS data gathering server, as well as the GPS client... and with the right framework it works very well on the web too
<14> great stuff!:)
<8> Yeah, there are some really great frameworks.
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