小编not*_*ick的帖子

我有一个长度为n的向量y.y(i)是1..m的整数.是否有更简单的方法将y转换为nxm逻辑矩阵yy,其中yy(i,j)= 1如果y(i)= j,否则为0？这就是我一直在做的事情:

% If m is known (m = 3 here), you could write it out all at once
yy = [y == 1; y== 2; y == 3];
yy = reshape(yy, n, 3);

要么

% if m is not known ahead of time
yy = [ y == 1 ];
for i = 2:m;
    yy = [ yy; y == i ];
end
yy = reshape(yy, n, m);