// demo of macros portrait & fchamp
//  limit circle
// Copyright Enpc 

xbasc();
part1()
// phase portrait : dimension 2
portrait(cycllim,'default',[-2,-2,2,2],[500,0.1],'f',[0,1;0.5,2]);
// field dynamic system
fchamp(cycllim,0,-2:0.2:2,-2:0.2:2,0)

//interactive 
portrait(cycllim,'default',[-2,-2,2,2],[100,0.1]);
