https://www.coursera.org/learn/machine-learning/lecture/9fHfl/basic-operations
1. 初始化矩阵
a = [1,2; 3,4; 5,6]
a =
1 2
3 4
5 6
v = 1: 6
v =
1 2 3 4 5 6
v = 1: 1: 10
v =
1 2 3 4 5 6 7 8 9 10
ones全1矩阵、
zeros全0矩阵、
rand随机矩阵（0 - 1）、
eye单位矩阵
one = ones(3, 3)
one =
1 1 1
1 1 1
1 1 1
zero = zeros(1, 3) zero = 0 0 0
rand = rand(1, 3)
rand =
0.55265 0.42458 0.14323
eye = eye(3)eye = Diagonal Matrix 1 0 0 0 1 0 0 0 1
原文：https://www.cnblogs.com/liwenchi/p/10834575.html