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Comments:
<0> hi. i need to convert a file consisting of floats to a file consisting of bytes.
<0> i'm experienced in c++, but i'd really like to use python for this
<1> well a file of floats already is a file of bytes ...
<0> basically, at the moment i can open and close files in python, and pickle stuff from/to files
<0> xihr, i need to convert the files into corresponding bytes (via some linear transformation)
<0> the floats, even
<1> "corresponding bytes"?
<1> you'll have to define the problem more clearly
<1> are they floats in text format and you want to write them out as IEEE binary floats or something?
<0> oh, sorry, i was unspecific
<0> the floats are standard 4-byte IEEE floats
<0> the input file is just a dump of those
<1> if you're asking how to read files in binary, then use the struct module
<0> yeah, at the moment i'm using temp = struct.unpack('f', file.read(4)); v = temp[0]
<0> it's rather inelegant but it works
<0> writing the bytes is a harder problem, though
<1> how is it harder
<1> you're not specifying what it is you're trying to do
<2> How about an example input and output
<0> it's rather hard to give examples of binary data
<1> if you're dealing with homogeneous data, you could also use the array module
<0> i just need to convert from 4-byte floats to 1-byte ints
<0> that's all
<1> so what problem are you having doing that?
<1> you already know about reading and writing files and the struct module ...
<0> no, i only about reading files with the struct module =)
<0> writing files, i don't know of
<1> aFile.write(aString)
<0> hmm, or perhaps file.write( struct.pack('b', v), 1 ) might work
<1> without the 1
<0> hmm... ah yes, it's automatic of course
<0> well, thanks for straightening my thoughts... i'll hack the thing for a while
<0> yay, it's pretty much working
<0> only that struct.pack('b', v) expects -128 <= v < 127
<0> -128 <= v <= 127 even
<0> whereas i have 0 <= v <= 255, i.e unsigned
<1> are you looking at the library documentation? http://www.python.org/doc/current/lib/module-struct.html
<1> use 'B', not 'b'
<0> millions of thanks... sorry, i'm just thinking aloud =)
<0> well, that's enough python for one night. still, thousands of thanks to you guys, you were exceptionally helpful for ircers =)
<3> I'm offended now
<3> what's wrong with ircers?
<1> well most IRC "help" channels are not very helpful
<1> but still that wasn't a great way to sign off :-)
<1> "thanks for your help, you guys didn't **** as hard as I expected"
<4> lol
<5> heh, gotta love when you accidently take down the wrong vlan and dont realize the office phones dropped :)
<5> woops, my bad ;)
<1> call it a drill
<5> hehe
<5> Yea
<6> Hello!
<7> Hello
<7> is any of you familiar with the Komodo IDE?
<8> I have a [] full of values. How can I get the last 4 of them?
<8> I should know this, I really should.
<8> arrray[-4::] is the answer
<9> array[-4:] is enough
<10> mornin' chaps
<8> good morning.
<11> hello
<1> hey
<11> i switched to asynchat for my client after all
<11> it was much simpler than twisted :)
<1> :-)
<11> although now i want to add a server to make a relay, and an example i saw used threading, is that necessary?
<1> unless you already know it well, the philosophy fits well, and it supports a protocol you plan on using, Twisted is not necessarily a good solution
<1> my understanding is that even a lot of the "supported" protocols are very sketchy, though I don't know that for a fact
<1> nah, just use asynchronous I/O, no need for threading
<11> ah, good
<11> although the example there isn't very good
<1> which example was this?
<11> on the docs, of the http server
<1> well there are non-threaded varieties too
<11> well, the one on asynchat is just a simple server. i found a test_asynchat.py which showed how to use asynchat for an outgoing connection (the docs weren't clear on this), but that's the one that used threading
<1> I think if you look there the threading is not really crucial to its operation, it's just so that they can fire up a thread AND test it
<1> in an actual server the thread would be totally unnecessary
<11> i thought so, but i don't know how to do it in a single thread
<1> there's a better example in the library documentation, hold
<11> ok
<1> there are better examples here: http://www.nightmare.com/medusa/
<1> basically the only reason a thread is used there is that they can start the server, do one test, and then quit
<11> ah, i see
<11> the docs look good, thanks :)
<11> by the way, how can i catch the exception when the host is unreachable? trying the self.connect doesn't work :/
<1> if you want to see a simple proxy, I wrote one I can show you
<11> that'd be great, thanks
<1> http://www.alcyone.com/tmp/proxy.py
<1> well self.connect is definitely where the exception will come from
<11> that's what i needed, thanks a lot :)
<1> or are you asking how to catch exceptions?
<11> no, i am trying the block, but it just spams me with "unhandled exception"
<11> it doesn't run the except: block
<1> you probably need the try clause at a lower level, it gets swallowed by .loop
<11> ah, hmm
<11> how do i do it?
<1> you'd have to show me your code, not sure where the problem is
<1> typically you'd do it when you create the server, so you'd catch it there before you enter the event loop
<11> ok, let me paste the block
<1> use a pastebin
<11> yes :)
<1> :-)
<11> http://rafb.net/paste/results/A27vZK92.html
<1> what's the exception that's being spammed?
<11> "warning: unhandled exception"
<1> my guess is that MUDConnection is now broken when that gets caught, so the exceptions are caused by other problems since the socket didn't connect
<1> yeah but it says what the exception was
<11> nope
<1> scroll back up through the spamming and see what the FIRST one was
<11> it just spams that until i ctrl+c
<1> huh
<11> hmm, let me redirect it, it's fast
<11> nothing, they're all the same
<11> let me print some debugging info
<1> hmm
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