Start3d([A,B,C]); Putaxes3d(3); fd=[ "z=x^2-y^2","x=[-2,2]","y=[-2,2]","ewns" ]; if(Isangle(), Sf3data("1",fd); , mf(s):=( regional(ang); ang=Getangle(); Startsurf(); Setangle(70,s); Xyzax3data("","x=[-3,3]","y=[-3,3]","z=[-1,5]"); Sfbdparadata("1",fd); Crvsfparadata("1","ax3d","sfbd3d",fd); if(Gccexists(), ExeccmdC("",[""]); ); Setangle(ang); ); ang=Getangle(); mf(ang_2); Setpara("saddle","mf(s)","s=[0,360]", ["Div=24","Out=y"]); ); Windispg();