Given [1,2,3,4,5], how can I do something like
1/1, 1/2, 1/3,1/4,1/5, ...., 3/1,3/2,3/3,3/4,3/5,.... 5/1,5/2,5/3,5/4,5/5
I would like to store all the results, find the minimum, and return the two numbers used to find the minimum. So in the case I've ...

Asked By joe calimar

Given [1,2,3,4,5], how can I do something like
1/1, 1/2, 1/3,1/4,1/5, ...., 3/1,3/2,3/3,3/4,3/5,.... 5/1,5/2,5/3,5/4,5/5
I would like to store all the results, find the minimum, and return the two numbers used to find the minimum. So in the case I've ...

Asked By joe calimar

How do I get the inverse of a matrix in python? I've implemented it myself, but it's pure python, and I suspect there are faster modules out there to do it.

Asked By Claudiu

How do I get the inverse of a matrix in python? I've implemented it myself, but it's pure python, and I suspect there are faster modules out there to do it.

Asked By Claudiu

A few years ago, it was proven that PRIMES is in P. Are there any algorithms implementing their primality test in Python? I wanted to run some benchmarks with a naive generator and see for myself how fast it is. I'd implement it myself, but I don't unders...

Asked By Claudiu

Recently I needed to do weighted random selection of elements from a list, both with and without replacement. While there are well known and good algorithms for unweighted selection, and some for weighted selection without replacement (such as modificatio...

Asked By Nick Johnson

How do you generate all the permutations of a list in Python, independently of the type of elements in that list?
For example:
permutations([])
[]
permutations([1])
[1]
permutations([1, 2])
[1, 2]
[2, 1]
permutations([1, 2, 3])
[1, 2, 3]
[1, 3, 2]
[2...

Asked By Ricardo Reyes

How do you generate all the permutations of a list in Python, independently of the type of elements in that list?
For example:
permutations([])
[]
permutations([1])
[1]
permutations([1, 2])
[1, 2]
[2, 1]
permutations([1, 2, 3])
[1, 2, 3]
[1, 3, 2]
[2...

Asked By Ricardo Reyes

I was playing around with my own Sudoku solver and was looking for some pointers to good and fast design when I came across this:
def r(a):i=a.find('0');~i or exit(a);[m
in[(i-j)%9*(i/9^j/9)*(i/27^j/27|i%9/3^j%9/3)or a[j]for
j in range(81)]or r(a[:i]+m+a...

Asked By Ville Salonen

I was playing around with my own Sudoku solver and was looking for some pointers to good and fast design when I came across this:
def r(a):i=a.find('0');~i or exit(a);[m
in[(i-j)%9*(i/9^j/9)*(i/27^j/27|i%9/3^j%9/3)or a[j]for
j in range(81)]or r(a[:i]+m+a...

Asked By Ville Salonen

This is a generalization of the "string contains substring" problem to (more) arbitrary types.
Given an sequence (such as a list or tuple), what's the best way of determining whether another sequence is inside it? As a bonus, it should return the index...

Asked By Gregg Lind

I have a bunch of keys that each have an unlikeliness variable. I want to randomly choose one of these keys, yet I want it to be more unlikely for unlikely (key, values) to be chosen than a less unlikely (a more likely) object. I am wondering if you would...

Asked By Nicholas Leonard

Here's the very dumb way:
def divisorGenerator(n):
for i in xrange(1,n/2+1):
if n%i == 0: yield i
yield n
The result I'd like to get is similar to this one, but I'd like a smarter algorithm (this one it's too much slow and dumb :-)
I c...

Asked By Andrea Ambu

In Python (specifically Python 3.0 but I don't think it matters), how do I easily write a loop over a sequence of characters having consecutive character codes? I want to do something like this pseudocode:
for Ch from 'a' to 'z' inclusive: #
f(Ch)
...

Asked By bigturtle

I could use some pseudo-code, or better, Python. I am trying to implement a rate-limiting queue for a Python IRC bot, and it partially works, but if someone triggers less messages than the limit (e.g., rate limit is 5 messages per 8 seconds, and the pers...

Asked By miniman

I could use some pseudo-code, or better, Python. I am trying to implement a rate-limiting queue for a Python IRC bot, and it partially works, but if someone triggers less messages than the limit (e.g., rate limit is 5 messages per 8 seconds, and the pers...

Asked By miniman

Here's the very dumb way:
def divisorGenerator(n):
for i in xrange(1,n/2+1):
if n%i == 0: yield i
yield n
The result I'd like to get is similar to this one, but I'd like a smarter algorithm (this one it's too much slow and dumb :-)
I c...

Asked By Andrea Ambu

I'm checking if two strings a and b are permutations of each other, and I'm wondering what the ideal way to do this is in Python. From the Zen of Python, "There should be one -- and preferably only one -- obvious way to do it," but I see there are at leas...

Asked By Kiv

There is a list of numbers.
The list is to be divided into 2 equal sized lists, with a minimal difference in sum. The sums have to be printed.
#Example:
>>>que = [2,3,10,5,8,9,7,3,5,2]
>>>make_teams(que)
27 27
Is there an error in th...

Asked By Lakshman Prasad

Is there a way to sum up a list of numbers faster than with a for-loop, perhaps in the Python library? Or is that something really only multi-threading / vector processing can do efficiently?
Edit: Just to clarify, it could be a list of any numbers, unso...

Asked By not-too-smatr