将矢量重新排列成矩阵

Question

在Matlab中我有以下向量:

a = [ 1 2 3 4 5 6 ];

我想构建一个矩阵,每行快速生成1个元素.输出矩阵应如下所示:

A =

 1     2     3
 2     3     4
 3     4     5
 4     5     6 

哪种方法最快？提前告诉你!

Answer 1

简单的矢量化解决方案:

a = [ 1 2 30 4 15 6 ]
m = 4;
n = 3;  %// If you want the last element of a to be the bottom right 
        %// element of your output then n must equal numel(a)-(m-1)

[r,c] = ndgrid(0:(m-1), 1:n);
a(r+c)

ans =

    1    2   30
    2   30    4
   30    4   15
    4   15    6