Find the minimum value using min and specify all dimensions. Then use find with two outputs to find the row and column indices of the matrix that equal the minimum value.
% demo data
m = [3 0 1 0 2; 2 2 0 0 3]
minval = min(m,[],'all');
[row, col] = find(m == minval)
Common pitfalls
min() has a second output that returns the indicies of the min value but, by default, it will return the row index of the first matching minimum value for each column.
[minval, idx] = min(m)
You can specify the linear option to return the linear index rather than a row index but this will still return the first matching minimum for each column, not all matches of the global minimum.
[minval, idx] = min(m,[],'linear')
If you specify all dimensions, it will return the first match of the minimum value, with or without the linear option.
[minval, idx] = min(m,[],'all')
