function define_zlim2(alpha,f,s)

alpha_max = max(alpha);
alpha_min = min(alpha);
f_max = max(f);
f_min = min(f);
s_max = max(s);
s_min = min(s);

aux_max = [alpha_max f_max s_max];
aux_min = [alpha_min f_min s_min];
zmax = max(aux_max);
zmin = min(aux_min);

fprintf(2,'variacao real = [ %24.15e %24.15e]\n', zmin, zmax);
zmag = max(abs(zmax),abs(zmin));
zmax = max(0.00001,zmax+0.00001*zmag);
zmin = min(-0.00001,zmin-0.00001*zmag);
zlim([zmin, zmax]);
