[x,y,z]=meshgrid(1:.3:10, -3:.2:3, -8:.3:8);
f=x.^4+y.^4+1.5*z.^4+2*x.^2.*y.^2+2*x.^2.*z.^2+2*y.^2.*z.^2-94*x.^2+78*y.^2-94*z.^2+1521;
const=0;
surfcv(x,y,z,f,const)
shading interp
rotate3d on
axis off
colormap([1 1 0])
light
view(140,6)
set(gcf,'color','b')
