fcontour - level curves on a 3D surface defined by a function
Draws level curves of a surface z=f(x,y). The level curves are drawn on a 3D surface. The surface is given by the external function f. See contour.
The optional arguments theta,alpha,leg ,flag,ebox, zlev, can be passed by a sequence of statements key1=value1, key2=value2,
flag,ebox,zlev. In this case, the order has no special meaning.
You can change the format of the floating point number printed on the levels by using xset("fpf",string) where string gives the format in C format syntax (for example string="%.3f"). Use string="" to switch back to default format and Use string=" " to suppress printing.
Enter the command fcontour() to see a demo.
deff("[z]=surf(x,y)","z=sin(x)*cos(y)");
t=%pi*[-10:10]/10;
fcontour(t,t,surf,10)
xbasc();fcontour(t,t,surf,10,ebox=[-4 4 -4 4 -1 1],zlev=-1,flag=[0 1 4])