cf.hash_array

cf.hash_array(array, algorithm=<built-in function openssl_sha1>)

Return a hash value of a numpy array.

The hash value is dependent on the data type and the shape of the array. If the array is a masked array then the hash value is independent of the fill value and of data array values underlying any masked elements.

Parameters

array: numpy.ndarray

The numpy array to be hashed. May be a masked array.

algorithm: hashlib constructor function

Constructor function for the desired hash algorithm, e.g. hashlib.md5, hashlib.sha256, etc.

New in version 3.14.0.

Returns

int

The hash value.

Examples

>>> a = np.array([[0, 1, 2, 3]])
>>> cf.hash_array(a)
-5620332080097671134

>>> a = np.ma.array([[0, 1, 2, 3]], mask=[[0, 1, 0, 0]])
>>> cf.hash_array(array)
8372868545804866378

>>> a[0, 1] = 999
>>> a[0, 1] = np.ma.masked
>>> print(a)
[[0 -- 2 3]]
>>> print(a.data)
[[  0 999   2   3]]
>>> cf.hash_array(a)
8372868545804866378

>>> a = a.astype(float)
>>> cf.hash_array(a)
5950106833921144220