How to copy data from a numpy array to another

Question

What is the fastest way to copy data from array b to array a, without modifying the address of array a. I need this because an external library (PyFFTW) uses a pointer to my

Answer 1

There are many different things you can do:

a=np.copy(b)
a=np.array(b) # Does exactly the same as np.copy
a[:]=b # a needs to be preallocated
a=b[np.arange(b.shape[0])]
a=copy.deepcopy(b)

Things that don't work

a=b
a=b[:] # This have given my code bugs