Speed Of Np.empty Vs Np.zeros

I am using numpy version 1.14.3 and python 2.7.12. Referencing this question, I am finding dramatically different speeds between initializing arrays with np.zeros and np.empty. Ho

Solution 1:

np.empty and np.zeros do different things.

np.empty creates an array from available memory space, leaving whatever values happened to be hanging around in memory as the values. These values may or may not be zeros.

np.zeros creates an array from available memory space, and then fills it with zeros for your chosen dtype. Obviously np.zeros has to do more work so it should be slower, since it's also writing to the memory allocated.

A more fair comparison would be between np.empty and np.ndarray.