Vector of indexes to create matrix by accessing elements of another matrix

Question

Consider an n-by-k matrix M and an p-by-1 vector of indexes V ranging from 1 to n. How can I create the p-by-k matrix C where each row corresponds to the entry of M referred to by the value in each row of V .

Example

M = 1 1
    1 2
    1 3
    1 4

and

V = 2
    1
    3

What I require is the matrix

C = 1 2
    1 1
    1 3

Answer 1

要将矩阵M的行V分配给矩阵C ，应编写：

C = M(V,:);