How could I remove the rows of an array if one of the elements of the row does not satisfy a condition?

Question

I would like to remove the rows of an array when the elements of third column of the array are less than specific amount. For example:

a=np.array([[2331.13,1         


        

Answer 1

You can do:

a[a[:,2]>=15.0, :]

Note the inversion of a[:,2]<15.0 to a[:,2]>=15.0, so that you're describing rows that you want to keep rather than remove.

If inverting your condition isn't as simple as that, you could also use ~:

a[~(a[:,2]<15.0), :]