function PI=GA_f622(x)
global MIN_offset MUL_factor Emin MDL Init_P Init_V
global FT Se Sde Su ex621f
% Fitness function evaluation of Example 6.2-2.

% PenChen Chou, 7-30-2001

Init_P=2*(rand-0.5)*35;
if abs(Init_P)<10, Init_P=10*sign(Init_P); end;
Init_V=0;

Se=GA_round4dp(x(1));
Sde=GA_round4dp(x(2));
Su=GA_round4dp(x(3));

% Get Y
[t, X, Y]=sim(MDL,[0 FT]);
I=find(t>0.5);
error=10*abs(Y(:,1)); err1=10*abs(Y(:,4));
error=error(I); err1=err1(I);
ERR=10*(30/abs(Init_P+0.001))*(sum(error)+sum(err1));
if ERR>MIN_offset, ERR=MIN_offset-10; end;
PI=ERR;
if MIN_offset>0
   PI=MIN_offset-PI;
end;
if Emin>ERR
   Emin=ERR; fprintf('\nERR=%f',ERR);
   %save ex622_data Se Sde Su ERR
   %pause(2)
else
   fprintf('>'); 
end;