[Numpy-discussion] Index array confusion...  Perry Greenfield
perry at stsci.edu Mon Dec 16 14:25:01 CST 2002  > And
performance, perhaps? Certainly. That was one big factor (more
with regard to memory demands than CPU demands).  > And; from
Todd's comment about a hypothetical built-in for the > purpose,
I assume there is no way of copying the contents of one slice >
to another without going via a temporary array? If you mean:
Without overwriting the slice being copied to with overlapping
slices (whether it's a problem depends on how they overlap and
whether one is reversed or not, and one other effect described
below) on the same array, that's generally true.  In numarray,
there are cases where the slice is copied internally in blocks.
It's possible that you could get away with  x[:] = x[-1::-1]  if
x is smaller than the blocksize being used. You would be crazy
to depend on this though :-) For large enough arrays (try 10000
elements), it definitely won't work.   More information about
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