function PI=GA_f614(x)
global MIN_offset MUL_factor Emin MDL r_deg Init_P Init_V
global V11 V12 V21 V22 W11 W12 b11 b21 c11 FT Mode
% Fitness function evaluation of Example 6.1-4

% PenChen Chou, 7-29-2001
Init_P=rand*180;
Init_V=0;
if Mode==0
   r_deg=rand*180;
   if r_deg<20, r_deg=20; end;
   if abs(r_deg-Init_P)<10, r_deg=Init_P+10; end;
else
   r_deg=180;
end   

V11=GA_round4dp(x(1));
V12=GA_round4dp(x(2));
V21=GA_round4dp(x(3));
V22=GA_round4dp(x(4));
b11=GA_round4dp(x(5));
b21=GA_round4dp(x(6));
W11=GA_round4dp(x(7));
W12=GA_round4dp(x(8));
c11=GA_round4dp(x(9));

% Get Y
[t, X, Y]=sim(MDL,[0:0.05:FT]);
I=find(t>1 & t<4);
error=100*abs(Y(:,1)); err1=100*abs(Y(:,4));
error=error(I); err1=err1(I);
ERR=10*(180*sum(error)/r_deg+sum(err1));
if Mode==1
    I=find(t>5.7);
    error=100*abs(Y(:,1)); err1=100*abs(Y(:,4));
    error=error(I); err1=err1(I);
    ERR=ERR+1*(180*sum(error)/r_deg+sum(err1));
end;
PI=ERR;
if MIN_offset>0
   PI=MIN_offset-PI;
   if PI<0, PI=10; end;
end;
if Emin>ERR
   Emin=ERR; fprintf('\nERR=%f',ERR);
   %save ex614_data V11 V12 V21 V22 W11 W12 b11 b21 c11 ERR
   %pause(2)
else
   fprintf('>'); 
end;