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: mci_phase_fx.m
    path of file: ./repos/bspm/thirdparty/spm12/toolbox/mci/models/phase
    
    the code of the file until where you have to start completion: function [f] = mci_phase_fx (x,u,P,M)
% Flow function for phase model
% FORMAT [f] = mci_phase_fx (x,u,P,M)
%
% x      state vector
% u      inputs
% P      parameter vector
% M      model structure
%
% f      dx/dt
%__________________________________________________________________________
% Copyright (C) 2015 Wellcome Trust Centre for Neuroimaging

% Will Penny and Biswa Sengupta
% $Id: mci_phase_fx.m 6548 2015-09-11 12:39:47Z will $

params = spm_unvec (P,M.pE);

a = params.sinCoeff;
b = params.cosCoeff;
w = params.intrinPhase;

D = M.n;
% initialise state matrix
f = zeros(D,1);

for i = 1:D,
    f(i)=w(i);

    
function [f] = mci_phase_fx (x,u,P,M)
% Flow function for phase model
% FORMAT [f] = mci_phase_fx (x,u,P,M)
%
% x      state vector
% u      inputs
% P      parameter vector
% M      model structure
%
% f      dx/dt
%__________________________________________________________________________
% Copyright (C) 2015 Wellcome Trust Centre for Neuroimaging

% Will Penny and Biswa Sengupta
% $Id: mci_phase_fx.m 6548 2015-09-11 12:39:47Z will $

params = spm_unvec (P,M.pE);

a = params.sinCoeff;
b = params.cosCoeff;
w = params.intrinPhase;

D = M.n;
% initialise state matrix
f = zeros(D,1);

for i = 1:D,
    f(i)=w(i);
    for j = 1:D,
        if ~(i==j)
            f(i) = f(i) + a(i,j)*sin(x(i)-x(j)) + b(i,j)*cos(x(i)-x(j));
        end