In article <[EMAIL PROTECTED]>,
Dan Bishop <[EMAIL PROTECTED]> wrote:
>Cameron Laird wrote:
>...
>> for hextuple in [(i, j, k, l, m, n)
>> for i in range(1, lim + 1) \
>> for j in range (1, lim + 2) \
>> for k in range (1, lim + 3) \
>> for l in range (1, lim + 4) \
>> for m in range (1, lim + 5) \
>> for n in range (1, lim + 6)]:
>> print hextuple
>>
>> I don't think the list comprehension helps, in this case--although
>> it hints at the temptation of an eval-able expression which is
>> briefer. More on that, later.
>
>from the recent "N-uples from list of lists" thread import cross
>
>for hextuple in cross(*[xrange(1, lim+p) for p in xrange(1, 7)]):
> print hextuple
>
Tangential remarks: cross product is *very* important; why
isn't it built in? Yes, I recognize that the recipes supplied
elsewhere are quite nice.
I've seen a lot of Fortran and C code of the "for (...) {for (...) { ..."
variety. I have a deep suspicion that most of them betray
fundamental miscomprehension of physical realities. It's very,
*very* unusual for any meaningful measurement to arise across a
medium-dimension product of real intervals. I invite
counterexamples. In the meantime, I'll persist in suspecting
that such computations are symptoms of a misunderstanding.
So: cross products are valuable, but particularly so when not
limited to crosses over numeric intervals.
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