How do I find the indices of the maximum (or minimum) value of my matrix?

5,561 次查看(过去 30 天)
The 'find' command only returns the indices of all the non-zero elements of a matrix. I would like to know how to find the indices of just the maximum (or minimum) value.

采纳的回答

MathWorks Support Team
编辑:MathWorks Support Team 2021-11-17
The "min" and "max" functions in MATLAB return the index of the minimum and maximum values, respectively, as an optional second output argument.
For example, the following code produces a row vector 'M' that contains the maximum value of each column of 'A', which is 3 for the first column and 4 for the second column. Additionally, 'I' is a row vector containing the row positions of 3 and 4, which are 2 and 2, since the maximums for both columns lie in the second row.
A = [1 2; 3 4];
[M,I] = max(A)
For more information on the 'min' and 'max' functions, see the documentation pages listed below:
To find the indices of all the locations where the maximum value (of the whole matrix) appears, you can use the "find" function.
maximum = max(max(A));
[x,y]=find(A==maximum)

更多回答(5 个)

Shakir Kapra
Shakir Kapra 2015-4-20
编辑:Shakir Kapra 2015-4-20
[M,I] = min(A)
where M - is the min value
and I - is index of the minimum value
Similarly it works for the max

indrajit das
indrajit das 2016-8-3
find(arr == max(arr));

Andrew Teixeira
Andrew Teixeira 2019-10-1
How about just:
A = magic(5);
[Amins, idx] = min(A);
[Amin, Aj] = min(Amins);
Ai = idx(Aj);
where your final matrix minima is located at [Ai, Aj]

Juanith HL
Juanith HL 2019-10-8
A = [8 2 4; 7 3 9]
[M,I] = max(A(:)) %I is the index maximun Here tu can change the function to max or min
[I_row, I_col] = ind2sub(size(A),I) %I_row is the row index and I_col is the column index
  1 个评论
Steven Lord
Steven Lord 2022-8-18
If you can use linear indices, instead I would recommend:
A = [8 2 4; 7 3 9];
[X, ind] = max(A, [], 'all', 'linear')
X = 9
ind = 6
This will tell us the maximum value in A is 9 and it is located in element 6 of A.

请先登录,再进行评论。


ANKUR KUMAR
ANKUR KUMAR 2017-9-19
Use this as a function and type [x,y]=minmat(A) to get the location of the minimum of matrix. for example:
>> A=magic(5)
>> [a,b]=minmat(A)
a =
1
b =
3
Save this as a function in your base folder and use it.
function [ a,b ] = minmat( c )
as=size(c);
total_ele=numel(c);
[~,I]=min(c(:));
r=rem(I,as(1));
a=r;
b=((I-a)/as(1))+1;
if a==0
a=as(1);
b=b-1;
else
a=r;
b=b;
end
end
  1 个评论
Steven Lord
Steven Lord 2020-9-6
Once you've stored this code in a file named minmat.m (see this documentation page for the basics of defining a function) you can call this like any other MATLAB function (as shown on this other documentation page.)

请先登录,再进行评论。

类别

Help CenterFile Exchange 中查找有关 Debugging and Analysis 的更多信息

产品

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by