How to identify area of a matrix with same values

Question

Mollymomo 2018-10-19

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/424914-how-to-identify-area-of-a-matrix-with-same-values

回答： YT 2018-10-19

I have a matrix of 10x10 filled with 0s and 1s. There are some areas of 0s enclosed by areas of 1s. I would like to be able to identify specific areas of 0s.

I am using ginput, so I would like to select a 0 from the matrix, and then I want Matlab to identify the area surrounding that specific 0. I believe this can be done with conv2, but I don't know how.

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

YT 2018-10-19

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/424914-how-to-identify-area-of-a-matrix-with-same-values#answer_342301

在 MATLAB Online 中打开

This question is similar to this one asked before ( https://mathworks.com/matlabcentral/answers/402080-how-to-find-the-neighbors-of-each-element-in-a-matrix#answer_321522)

So if I understand it corect you want something like this

%small 5x5 example matrix
A = [0 1 0 0 0;
     1 1 0 0 0;
     0 0 1 1 1;
     0 0 1 0 1;
     0 0 1 1 1];
%create matrix with zeros with size of A
M = zeros(size(A));
%use the coordinates from ginput; M(row,col)
M(1,1) = 1;
%convolution
C = conv2(M,[1,1,1;1,0,1;1,1,1],'same')>0;
%return indices
[row col] = find(C>0);
%return values (which in your case isnt really interesting cuz will only returns 1's)
A(C)