ndarray reshape? about ndarray HOT 3 CLOSED

You can easily write on yourself, but the reason that no reshape operations are supported currently is that such a thing would require reallocating the underlying array. For example, to reshape a 2D array into a 1D array you could do something like:

var x = ndarray(y.data, [y.shape[0] * y.shape[1]])

Of course this only works if y is packed tightly and if y's offset is 0.

from ndarray.

What's the problem with reallocation? My use case is to access all elements of an ndarray irrespective of its shape, and I don't know how to do that (array is a subset) as there is also no flatten/ravel function.

from ndarray.

I was looking for reshape() operation for ndarray, then came across this old issue...

such a thing would require reallocating the underlying array

The in-place reshape I wish to have, is like the one by numpy, would not change the underlying array. Why would it require reallocation of underlying array??

>>> import numpy as np
>>> np.array([1, 2, 3, 4, 5, 6])
array([1, 2, 3, 4, 5, 6])
>>> a = np.array([1, 2, 3, 4, 5, 6])
>>> a
array([1, 2, 3, 4, 5, 6])
>>> a.reshape(2, 3)
array([[1, 2, 3],
       [4, 5, 6]])
>>> a.reshape(3, 2)
array([[1, 2],
       [3, 4],
       [5, 6]])
>>> a.reshape(3, 3)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: cannot reshape array of size 6 into shape (3,3)
>>> a.reshape(6)
array([1, 2, 3, 4, 5, 6])

from ndarray.