Python中的 numpy.tril()
numpy.tril(a, k=0) :返回数组的副本,其中三角形 wrt k的下部
参数 :
a : input array
k : [int, optional, 0 by default]
Diagonal we require; k>0 means diagonal above main diagonal or vice versa.
返回:
Lower triangle of a, having same shape and data-type as a.
# Python Programming illustrating
# numpy.tril method
import numpy as geek
# string input
a = geek.matrix([[1, 21, 30],
[63 ,434, 3],
[54, 54, 56]])
print("Main Diagonal elements : \n", geek.tril(a), "\n")
print("Diagonal above main Diagonal elements : \n", geek.tril(a, 1), "\n\n")
print("Main Diagonal elements : \n", geek.tril(a, -1))
输出 :
Main Diagonal elements :
[[ 1 0 0]
[ 63 434 0]
[ 54 54 56]]
Diagonal above main Diagonal elements :
[[ 1 21 0]
[ 63 434 3]
[ 54 54 56]]
Main Diagonal elements :
[[ 0 0 0]
[63 0 0]
[54 54 0]]