Running Cumulative sum of 1d NumPy Array

Question

I have a numpy array like

x=np.array([1,2,3,4])

I want to create another numpy array y which is the cumulative sum of x, so that

Answer 1

Another option is:

y = np.add.accumulate(x)

which is often times faster than np.cumsum even though the documentation says they are equivalent.

Answer 2

y = np.cumsum(x)

See http://docs.scipy.org/doc/numpy/reference/generated/numpy.cumsum.html