global A, global B, global epsr
B=1.36e-03;
epsr=1.0e-06;

A=0.21;
[z0 tz0]=rk4("fsurf",[0;0;0],0,0.05,20000);
A=0.23;
[z1 tz1]=rk4("fsurf",[0;0;0],0,0.05,20000);
A=0.5;
[z2 tz2]=rk4("fsurf",[0;0;0],0,0.005,3200);
A=1.;
[z3 tz3]=rk4("fsurf",[0;0;0],0,0.005,1500);
A=1.5;
[z4 tz4]=rk4("fsurf",[0;0;0],0,0.005,800);
A=1.9;
[z5 tz5]=rk4("fsurf",[0;0;0],0,0.005,700);
A=2.5;
[z6 tz6]=rk4("fsurf",[0;0;0],0,0.0025,1000);
h=plot(z0(1,:),z0(2,:),z1(1,:),z1(2,:),z2(1,:),z2(2,:),z3(1,:),z3(2,:),z4(1,:),z4(2,:),z5(1,:),z5(2,:),z6(1,:),z6(2,:));
axis([0 3 0 30])
set (h,"linewidth",2);