如果有两个矩阵a和b，a（b）在matlab中做了什么？

Question

If I have a matrix, say 如果我有一个矩阵，说

a = [1 2 3;
     4 5 6]

and 和

b = [2 2 2;
     3 3 3]

when I do a(b) in matlab, I get the answer as 当我在matlab中做（b）时，我得到了答案

a(b) = [4 4 4;
        2 2 2]

what exactly is happening here ? 到底发生了什么？

Answer 1

You're indexing a with each item in b . 您正在为b每个项目编制索引。 a(2) = 4 and a(3) = 2 a(2) = 4且a(3) = 2

so 所以

c = [a(2) a(2) a(2); a(3) a(3) a(3)]

is what you're seeing. 就是你所看到的。