[Numpy-discussion] Numpy float precision vs Python list float issue
Mon Apr 20 16:38:26 CDT 2009
Ruben Salvador wrote:
> Anyway, this 'deepcopy' really surprised me. I have now looked for it
> and I think I get an idea of it, though I wouldn't expect this
> difference in behavior to happen. From "my logical" point of view a copy
> is a copy, and if I find a method called copy() I can only expect it
> to...copy (whether I am copying compound or "simple" objects!!).
I think this also highlights an advantage of numpy - a 2-d array is a
2-d array, NOT a 1-d array of 1-d arrays. When you used lists, you were
using a list-of-lists, so copying copied the main list, but only
referenced the interval lists.
One other note: if you do a complex computation with floats, then
reverse it, and get back EXACTLY the same numbers, you can be pretty
sure something is wrong!
Christopher Barker, Ph.D.
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