Convert array of indices to 1-hot encoded numpy array

Question

I want to encode a 1-D numpy array: x = array([1,0,3]) As a 2-D 1-hot array y = array([[0,1,0,0], [1,0,0,0], [0,0,0,1]]) Suggest me some faster technique other than looping. Select the correct answer from above options

Answer 1

@Anisha, Refer to the following code it may help. >>> x = [1, 0, 3] >>> z = np.max(x) + 1 >>> np.eye(z)[x] array([[ 0., 1., 0., 0.], [ 1., 0., 0., 0.], [ 0., 0., 0., 1.]]) Alernatively, you can use: >>> x = np.array([1, 0, 3]) >>> z= np.zeros((3, 4)) >>> z[np.arange(3), x] = 1 >>> y array([[ 0., 1., 0., 0.], [ 1., 0., 0., 0.], [ 0., 0., 0., 1.]])