3D plot doesn't show the whole curve

[Romain Gontero]

Hello everyone, i'm trying to plot a 3d surface in parametric mode, the code is the following :

set parametric
set angle degree
set urange [0:180]
set vrange [-90:90] 
a=10
b=1
c=1
r1(u,v) = c*b*a/sqrt(a**2*c**2*sin(u)**2*sin(v)**2-b**2*c**2*sin(u)**2*sin(v)**2-a**2*b**2*sin(u)**2+b**2*c**2*sin(u)**2+a**2*b**2)
splot u,v,r1(u,v) w pm3d at s

But when i plot the curve, the peak of the curve is missing, there should be a peak value of 10 but it show me a peak of 5... Any idea ?
Thank you !

[Hans-Bernhard Broeker]

This is most likely a sampling artifact. You'll want to up the 'set samples' and 'set isosamples'.

[Romain Gontero]

Thank you a lot Hans, increasing isosample value worked !