function F_resultant = postprocessing_contact_force(Dir_contact,F_contact)
%{
Function for defining the resultant contact force.
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Syntax :
F_resultant = postprocessing_contact_force(Dir_contact,F_contact)
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Function Description :
This function defines the resultant contact force associated with forces
applying on each of the points on the humeral head. The inputs for this
function are a structure and a matrix containing the direction and the
magnitude of the forces at each of the points on the humeral head for every
time step, respectively.
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%}

F_resultant = zeros(3,1);

% define the resultant force at/around HH due to the contact
for i = 1:size(F_contact,1)-1
    for j = 2:size(F_contact,2)-1
        
        F_resultant = F_contact(i,j)*Dir_contact{i,j} + F_resultant;
        
    end
end

% the contact force associated with the top point
F_resultant = F_contact(1,1)*Dir_contact{1,1} + F_resultant;

% the contact force associated with the bottom point
F_resultant = F_contact(size(F_contact,1),size(F_contact,2))*Dir_contact{size(F_contact,1),size(F_contact,2)} + F_resultant;

return;