numpy.triu — NumPy v2.2 Manual (original) (raw)
Upper triangle of an array.
Return a copy of an array with the elements below the _k_-th diagonal zeroed. For arrays with ndim
exceeding 2, triu will apply to the final two axes.
Please refer to the documentation for tril for further details.
See also
lower triangle of an array
Examples
import numpy as np np.triu([[1,2,3],[4,5,6],[7,8,9],[10,11,12]], -1) array([[ 1, 2, 3], [ 4, 5, 6], [ 0, 8, 9], [ 0, 0, 12]])
np.triu(np.arange(345).reshape(3, 4, 5)) array([[[ 0, 1, 2, 3, 4], [ 0, 6, 7, 8, 9], [ 0, 0, 12, 13, 14], [ 0, 0, 0, 18, 19]], [[20, 21, 22, 23, 24], [ 0, 26, 27, 28, 29], [ 0, 0, 32, 33, 34], [ 0, 0, 0, 38, 39]], [[40, 41, 42, 43, 44], [ 0, 46, 47, 48, 49], [ 0, 0, 52, 53, 54], [ 0, 0, 0, 58, 59]]])