[Numpy-discussion] How are non-contiguous arrays created?

[Chris Barker]

Norman Davis wrote:
> How is a
> non-contiguous array created?

By slicing an array. Since slicing created a "view" into the same data,
it may not represent a contiguous portion of memory. Example:

>>> from Numeric import *
>>> a = ones((3,4))
>>> a
array([[1, 1, 1, 1],
       [1, 1, 1, 1],
       [1, 1, 1, 1]])
>>> a.iscontiguous()
1
# a newly created array will always be contiguous

>>> b = a[3:3,:]
>>> b.iscontiguous()
1
# sliced this way, you get a contiguous array
>>> c = a[:,3:3]
>>> c.iscontiguous()
0
#but sliced another way you don't

-Chris


-- 
Christopher Barker, Ph.D.
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