Replacing matrix n column values

Hello community,

If I want to make every negative value inside a matrix equal to zero I would use the following code:

MyMatrix(MyMatrix<0) = 0

And If i wanted to make only one column negative values zero I'd use this:

n = 5; % The column i want to replace.
MyMatrix( MyMatrix(:,n)<0, n ) = 0

The real issue is that now I have a 50x100 matrix where I need to apply the previous idea (make every negative value equal to zero) but within columns 70 to 80(range). This could be easily done with a loop, but I'm sure there is a way to work around it.

Any ideas?

Thank you,

Santos

Answer 1

[James Tursa]

E.g.,

temp = A(:,70:80);
temp(temp<0) = 0;
A(:,70:80) = temp;

[Santos García Rosado]

That's it! Thank you James!

Answer 2

[Sergey Kasyanov]

Hello,

There are some no pretty but working solutions,

n = [70, 80];
%A is MyMatrix
%1
A(A(:).' < 0 &...
    (1:numel(A)) > size(A, 1) * (n(1) - 1) &...
    (1:numel(A)) <= size(A, 1) * (n(2))) = 0;
%2
A(A < 0 &...
    repmat(1:size(A, 2), size(A, 1), 1) >= n(1) &...
    repmat(1:size(A, 2), size(A, 1), 1) <= n(2)) = 0;
%3
n = [70:80]
A(:, n) = A(:, n) .* (A(:, n) >= 0);

[Santos García Rosado]

Thank you Sergey! Check Jame's solution.