looking for a neat solution to a nested loop problem

[André Malo]

* Tom P wrote:

> consider a nested loop algorithm -
> 
> for i in range(100):
>      for j in range(100):
>          do_something(i,j)

> 
> Now, suppose I don't want to use i = 0 and j = 0 as initial values, but
> some other values i = N and j = M, and I want to iterate through all
> 10,000 values in sequence - is there a neat python-like way to this? I
> realize I can do things like use a variable for k in range(10000): and
> then derive values for i and j from k, but I'm wondering if there's
> something less clunky.

you mean:
    do_something((i + N) % 100, (j + M) % 100)

?

I'd define my own range function doing exactly that.

def rrange(count, start=0):
    for j in xrange(count):
        yield (j + start) % count

(untested)

Or use some itertools magic for that. It might be faster.

nd
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