Maximum value of matrix

Question

mingcheng nie 2022-10-29

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1838658-maximum-value-of-matrix

评论： mingcheng nie 2022-10-29

Hi there,

If we have a complex matrix A, size of (N,M), is there any efficient way to keep the maximum 6 absolute values in A and set others to be zeros? like abs(A(n,m)), keep the top6 biggest one, then set rest to 0.

Really appreciate for anyone leave a comment.

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Kevin Holly 2022-10-29

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1838658-maximum-value-of-matrix#answer_1086723

在 MATLAB Online 中打开

% Generate random matrix

N = 34;

M = 23;

A = rand(N,M);

% Sort from highest to lowest

values = sort(abs(A(:)), 'descend')

values = 782×1

0.9998 0.9985 0.9980 0.9971 0.9965 0.9962 0.9950 0.9924 0.9914 0.9913

% top 6

values(1:6)

ans = 6×1

0.9998 0.9985 0.9980 0.9971 0.9965 0.9962

values(6)

ans = 0.9962

B = (A>=values(6)).*A

B = 34×23

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.9980 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.9985 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

imshow(B)