Sorting arrays in NumPy by column

Question

How can I sort an array in NumPy by the nth column?

For example,

a = array([[9, 2, 3],
           [4, 5, 6],
           [7, 0, 5]])

Answer 1

#for sorting along column 1

indexofsort=np.argsort(dataset[:,0],axis=-1,kind='stable') 
dataset   = dataset[indexofsort,:]