You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: u_FourierComplete.m
    path of file: ./repos/VBA-toolbox/modules/DCM
    
    the code of the file until where you have to start completion: function [u,dudx,dudp] = u_FourierComplete(x,P,t,in)
% input function for free-form (Fourier decomposition) deterministic DCM
% function [u,dudx,dudp] = u_FourierComplete(x,P,t,in)
% IN:
%   - x: [useless]
%   - P: nW*nuX1 vector of Fourier projection parameters, where nW is the
%   number of Fourier basis functions and nu is the dimensionality of the
%   output
%   - t: time at which the Fourier basis set is evaluated
%   - in: user-defined structure containing the set of Fourier frequencies
% OUT:
%   - u: the nuXnt matrix of outputs, where nt is the length of the
%   argument t.
%   - dudx: [useless]
%   - dudp: gradient wrt the parameters

% construct Fourier basis at time t
i0 = find(in.W==0);

    
function [u,dudx,dudp] = u_FourierComplete(x,P,t,in)
% input function for free-form (Fourier decomposition) deterministic DCM
% function [u,dudx,dudp] = u_FourierComplete(x,P,t,in)
% IN:
%   - x: [useless]
%   - P: nW*nuX1 vector of Fourier projection parameters, where nW is the
%   number of Fourier basis functions and nu is the dimensionality of the
%   output
%   - t: time at which the Fourier basis set is evaluated
%   - in: user-defined structure containing the set of Fourier frequencies
% OUT:
%   - u: the nuXnt matrix of outputs, where nt is the length of the
%   argument t.
%   - dudx: [useless]
%   - dudp: gradient wrt the parameters

% construct Fourier basis at time t
i0 = find(in.W==0);
in.W(i0) = [];
X = zeros(2*length(in.W),length(t));
for i = 1:length(t)
    X(:,i) = [cos(in.W(:).*pi.*t(i)./in.T);sin(in.W(:).*pi.*t(i)./in.T)];
end