porsche_circle_x3opt_y3opt_r20_get_grad_eq_constr.m

function grad_eq_constr = porsche_circle_x3opt_y3opt_r20_get_grad_eq_constr(model)
%function grad_eq_constr = porsche_get_grad_eq_constr(mu,z)
%
% DOKU SCHREIBEN!!!
%
% Oliver Zeeb, 31.05.2011

% old: nur x3 und y3 als paramter
% grad_eq_constr(1) = 2* (model.x3 - model.pmacro(3,1));
% grad_eq_constr(2) = 2* (model.y3 - model.pmacro(3,2));

% new: beliebig viele punkte (x_n,y_n) als parameter möglich:
x_ind_1=0;
x_ind_2=-1;
y_ind_1=0;
y_ind_2=0;
grad_eq_constr = zeros(length(model.mu_names)/2, length(model.mu_names));
for k=1:length(model.mu_names)
    position_in_pmacro = str2double(model.mu_names{k}(2));
    x_or_y = model.mu_names{k}(1);
    if x_or_y == 'x'
        x_ind_1 = x_ind_1+1;
        x_ind_2 = x_ind_2+2;
        x = getfield(model, model.mu_names{k});
        x_fix = model.mittelpunkt(1);
        grad_eq_constr(x_ind_1,x_ind_2) = 2*(x-x_fix);
    elseif x_or_y == 'y'
        y_ind_1 = y_ind_1+1;
        y_ind_2 = y_ind_2+2;
        y = getfield(model, model.mu_names{k});
        y_fix = model.mittelpunkt(2);
        grad_eq_constr(y_ind_1,y_ind_2) = 2*(y-y_fix);
    else
        error('unknown entry in model.mu_names');
    end
end