How to delete nonzero values at the end of a matrix

Assume I have the following array:

M = [1 1 1; 0 2 2; 3 3 0; 4 4 0; 0 5 0]

M = 5×3

1 1 1 0 2 2 3 3 0 4 4 0 0 5 0

How do I set all elements from the end of each row to the first nonzero value to NaN?

The result should look like this:

M = [1 1 1; 0 2 2; 3 3 NaN; 4 4 NaN; NaN 5 NaN]

M = 5×3

1 1 1 0 2 2 3 3 NaN 4 4 NaN NaN 5 NaN

It is important that only the zero values at the end are set equal to NaN and not all elements that are equal to zero.

Thank you!

Answer 1

[Chunru]

M = [1 1 1; 0 2 2; 3 3 0; 4 4 0; 0 5 0]

M = 5×3

1 1 1 0 2 2 3 3 0 4 4 0 0 5 0

for i=1:size(M, 2)
    idx = find(M(:, i), 1, 'last');
    M(idx+1:end, i) = nan;
end
M

M = 5×3

1 1 1 0 2 2 3 3 NaN 4 4 NaN NaN 5 NaN

%M = [1 1 1; 0 2 2; 3 3 NaN; 4 4 NaN; NaN 5 NaN]

[Mister Finance]

Exactly what I was looking for. Thanks a lot!