[FIXED] Reference of a single numpy array element

Issue

Lets say I have a numpy array like

x = np.arange(10)

is it somehow possible to create a reference to a single element i.e.

y = create_a_reference_to(x[3])
y = 100 
print x
[  0   1   2 100   4   5   6   7   8   9]

Solution

You can't create a reference to a single element, but you can get a view over that single element:

>>> x = numpy.arange(10)
>>> y = x[3:4]
>>> y[0] = 100
>>> x
array([0, 1, 2, 100, 4, 5, 6, 7, 8, 9])

The reason you can't do the former is that everything in python is a reference. By doing y = 100, you're modifying what y points to - not it's value.

If you really want to, you can get that behaviour on instance attributes by using properties. Note this is only possible because the python data model specifies additional operations while accessing class attributes - it's not possible to get this behaviour for variables.

Answered By - loopbackbee