Max()-function and multiple dimensions
显示 更早的评论
Hello,
I'm trying to maximize a matrix that is of several dimensions. I also need to know the locations of the maximized value, which is actually the problem. How do I go about doing this in the most simple way?
So, for example, x=rand(10,10,10,10,10); Of course, by simple max(max(max(max(x) I could get the maximal value of x. How about the location? (for example the maximum could be located in x(1,2,3,2,4))
Cheers,
M
1 个评论
Image Analyst
2014-8-10
I think you're getting only answers on how to locate the max value because no one knows what you want to do to maximize the array. What is the array dependent on such that changing those parameters will maximize the array? And what does it mean to maximize an array, as opposed to a single value. Do you want to vary some parameter, say lambda or whatever you want to call it, such that the sum, or mean, of all the values in the array is maximized?
采纳的回答
Ahmet Cecen
2014-8-9
编辑：Ahmet Cecen
2014-8-9
Do:
[C I]=max(x(:));
now C is the maximum value, I is the index of where it is, so that x(I) is C.
If you want the 5D coordinates explicitly, then read ind2sub.
3 个评论
E.g.:
[cPos{1:ndims(x)}] = ind2sub(size(x), I);
Pos = [cPos{:}];
Shivanand Venkanna Sheshappanavar
2016-10-25
what if the matrix is a 2D matrix ? We need maxval, rowindex and columnindex
Steven Lord
2016-10-25
The solution Ahmet and Jan posted works fine for 2-D matrices, 5-D arrays, etc.
更多回答（1 个）
Azzi Abdelmalek
2014-8-9
编辑：Azzi Abdelmalek
2014-8-10
Edit
A=rand(10,10,10,10,10);
[max_value,idx]=max(A(:));
q=['[' sprintf('x%d,',1:ndims(A))];
q(end)=']';
eval([q '=ind2sub(size(A),idx)'])
eval(['x=' q])
1 个评论
类别
在 帮助中心 和 File Exchange 中查找有关 Matrix Indexing 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
Translated by 
