🌐 Mailman 3 October 2005 - Tutor - python.org

Postgresql+Python -tutorial?
by Olli Rajala Feb. 11, 2006

Feb. 11, 2006

Hi! I've been using MySQL up this day, but would like to convert my program to use Postgresql. There seems to be awful lots of tutorials for MySQL+Python, but not so many for Postgresql+Python. Where should I start? I'm not very good at database things, but have written some little programs with MySQL+Python/Php/Java. So, if you have some good tutorials or something else info, I'd be glad to know! Oh, I can install additional modules, but it would be great if Ubuntu had them... Thanks! -- Olli Rajala <>< Tampere, Finland http://www.students.tut.fi/~rajala37/ "In theory, Theory and Practice should be the same. But in practice, they aren't." - Murphy's Proverbs

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What does Python gain by having immutable types?
by Tony C Nov. 15, 2005

Nov. 15, 2005

A friend recently asked my this didn't modify his original string variable s1="this is a string" s1.replace("is a", "is a short") "this is a short string" print s1 "this is a string" After showing him to change it to this s1 = s1.replace("is a", "is a short") print s1 "this is a short string" He then asked Why is it that the sort operation modfies the original list variable? l1=[] l1.append(3) l1.append(44) l1.append(1) l1.append(22) l1 [3, 44, 1, 22] l1.sort() l1 [1, 3, 22, 44] I don't know, but I think it has something to do with strings being immutable, whiles lists are mutable. So, other than the non-informative answer " because that's how the language was written" are there any other reasons how Python benefits from immutable types? Does it really matter if s1 is a different object, so long as it contains the expected modified string? The list variable is the same object, and contains the sorted list, so why bother with the complexity of immutable types at all?

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Question about resetting values
by Nathan Pinno Nov. 12, 2005

Nov. 12, 2005

I am writing a Blackjack program, and was wondering how to reset the values to zero, e.g. cash = 0? Thanks, Nathan Pinno, Crew, Camrose McDonalds and owner/operator of Woffee

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os command
by Johan Geldenhuys Nov. 3, 2005

Nov. 3, 2005

I have script that calls a system command that I want to run for 5 minutes. """ import os cmd = 'tcpdump -n -i eth0' os.system(cmd) """ I can start a timer after the cmd is issued, but I don't know how to send a control signal to stop the command after I issued it. This is normally from the shell ^c. This cmd my run in more than one thread on different interfaces and I don't whant all of then stopped at once. I think the best way is to make a thread for each interface where the cmd can be issued and stopped without the danger of stopping he wrong thread. Can anybody help? Thanks Johan

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while/if/elif/else loops
by Zameer Manji Nov. 1, 2005

Nov. 1, 2005

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 I'm new to programming and python. I've have recently been experimenting with while/if/elif/else loops and I've created a simple number guessing game. Now I want to create a coin tossing game, but I don't know how to structure it in python. The code I already have (but it's not working) is below. #Coin Toss Game print "This game will simulate 100 coin tosses and then tell you the number of head's and tails" import random tosses = 0 heads = 0 tails = 0 while tosses = 100<0: coin = randrange(1) tosses +=1 if coin == 0: heads +=1 print "Heads" else: tails +=1 Print "Tails" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (MingW32) iQEVAwUBQ2accw759sZQuQ1BAQqoyQgAsmVhRidMC1/WpQms6fChX+z62DWSpmRW qiY9F7bZAYZusyNsHHDUpuTAYdI0LXxgLVmYBKDz3tKhVCbEZTn9FUwgw5A2thYy I5o82tWXZnIpgmFIN2AysAj2dCI4mSfi/IJjE5JvG+IFELWigMb9Pf6tap4HiB71 IBayql8MN1XrA2zv8fXQs35zVwxnBUSvAHZuUBLi4hDcPxY/d71X/JHqfqpf3svS ClzUlYqLhXld+39/aiRFKOXHyVCnfsEUcAXB45r110Q3K+7KegwgX4Js8qL5dA66 d74HlLMb6Cp6G5AlNdQoKDin8jlMloxeQpb60hS+HmnBwkEFukyNHA== =QMuB -----END PGP SIGNATURE-----

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help with prime number program
by andrade1＠umbc.edu Nov. 1, 2005

Nov. 1, 2005

Hello I am trying to write a program that will figure out if a number is prime or not. Currently this is the code that I have: import math def main(): number=input("Please enter a positive whole number greater than 2: ") for value in range(2, number-math.sqrt): if number % value == 0: print number, "is not prime" exit print number, "is prime" main() my problem is that the output prints both statements whether the number is prime or not. How could I get it to only print the one statement saying that 49 is not a prime number? enter a number greater than 2: 49 49 is not prime 49 is prime

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Tainted characters and CGI
by Tim Johnson Oct. 31, 2005

Oct. 31, 2005

Hello: I need to tighten my handling of CGI transmissions. I particular, I need to develop a strategy of safely dealing with "tainted" characters. I'd appreciate any pointers to documentation and resources regarding this matter, as well as comments and caveats. At this time and for the forseeable future, we will be running our CGI services on *nix systems. Thanks tim -- Tim Johnson <tim(a)johnsons-web.com> http://www.alaska-internet-solutions.com

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Re: [Tutor] (no subject)
by Roberts, Alice Oct. 31, 2005

Oct. 31, 2005

Well, I'm looking into os.spawnl with os.P_WAIT, now. Thanks, -----Original Message----- From: Alan Gauld [mailto:alan.gauld@freenet.co.uk] Sent: Monday, October 31, 2005 1:57 PM To: Roberts, Alice; tutor(a)python.org Subject: Re: [Tutor] (no subject) > My os.system() isn't waiting for exit status, jumping right into next > os.system(). Are you sure it isn't just running very quickly? The time it takes to display stuff on a screen is significant - all those phosphorescent pixels :-) os.system doesn't have to wait for that so it tends to run programs much faster than normal... Just a thought, Alan G.

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Newbie Question - Python vs Perl
by Scott Clausen Oct. 31, 2005

Oct. 31, 2005

As a newbie to Python I'd like to know if someone can tell me some strengths and weaknesses of this language. The reason I'm asking is a friend told me I should learn Perl over Python as it's more prevalent. I'm going to be using it on a Mac. I'd appreciate hearing any views on this topic. My own view is that it's always good to learn new things as you then have more tools to use in your daily programming. Thanks in advance. Scott

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(no subject)
by Roberts, Alice Oct. 31, 2005

Oct. 31, 2005

Hi, My os.system() isn't waiting for exit status, jumping right into next os.system(). import os DIR = 'v:/pam/batch/ambac/' CMD1 = DIR + 'Prices_Prep.cmd' CMD2 = DIR + 'positions.cmd' CMD3 = DIR + 'ftp_hub.cmd' CMD4 = DIR + 'import_prices.cmd' try: os.system(CMD1) except IOError, (errno, strerror): print " E/S(%s): %s" % (errno, strerror) #result=os.system # print result try: os.system(CMD2) except IOError, (errno, strerror): print " E/S(%s): %s" % (errno, strerror) #result=os.system # print result try: os.system(CMD3) except IOError, (errno, strerror): print " E/S(%s): %s" % (errno, strerror) #result=os.system # print result try: os.system(CMD4) except IOError, (errno, strerror): print " E/S(%s): %s" % (errno, strerror) #result=os.system # print result Any thoughts? Thanks, Alice Roberts Ambac Assurance Corp.

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