How To Add 2 Columns In Numpy Ndarray?

I have an numpy ndarray like below: [[1 9 1 1] [9 3 1 1] [1 9 9 1] [8 2 4 7]] I want to add last 2 columns values to get below result [[1 9 2] [9 3 2] [1 9 10] [8 2 11]]

Solution 1:

Sum, then drop the last column

myArray[:, -2] = myArray[:,-2] + myArray[:,-1] 
myArray = myArray[:,:-1]