Write MatLab commands to find the index of the max value in the bold area of A

I also need to find find the index of the maximum value in the bold area of A.

A>>
7.24  0.80  *7.31*  *9.24*  *3.09*

1.06  0.06  *8.97*  *1.37*  *0.55*

8.67  8.88  *9.92*  *0.71*  *0.90*

3.45  9.01  *9.15*  *4.80*  *2.29*

4.56  5.16  *5.33*  *7.10*  *7.61*

1.16  0.64  *0.08*  *8.76*  *8.06*

8.96  6.23  *9.96*  *6.93*  *7.71*

8.15  6.84  *6.95*  *1.88*  *7.36*

4.75  1.54   0.28   3.10   9.04

2.95  8.42   2.33   1.38   4.39

2.28  4.74   7.54   7.94   3.73

7.48  3.01   7.61   8.38   4.85

I tried to do B=find(A(1:8,3:5>2 & 1:8,3:5<=6)) but I not sure if the command is the right one here to find the values in the bold area and [m,n]=max(max(A(1:8,3:5))

Answer 1

[Walter Roberson]

T = A(1:8, 3:5);
[m, idx] = max(T(:));
[r, c] = idx2sub(size(T), idx);
B = [r, c+2];

This would leave B in [row column] format relative to A. You weren't clear as to the form of the index you wanted, and you weren't clear if you wanted the index within the sub-array or within all of A.

[marie]

the index of the max value in the bold area of A

[Walter Roberson]

That's what my code calculates, in row and column form. If you want it in scalar index form then probably the easiest way would be to use

B = sub2idx(size(A), r, c);

[Jan]

sub2idx? Is this sub2ind?

Answer 2

[Andrei Bobrov]

variant

B = -inf(size(A));
B(1:8,3:5) = A(1:8,3:5);
[m,n] = find(abs(B - max(B(:))) < eps(100));