function [Ms] = construir_matriz_signos( M )
%UNTITLED2 Summary of this function goes here
%   Detailed explanation goes here

    dimension = length(M);
    % Ms = zeros(dimension);
    Ms = M ;
    
    for f = 1:dimension
        for c = 1:dimension
            Ms(f,c) = (-1)^(f+c);
        end
    end
    
end