#http://www.mathcurve.com/surfaces/algebricsu/algebricsu.shtml

vertices = dimension1:101 dimension2:101

x = from (-4) to (4) dimension1
z = from (-4) to (4) dimension2

a = (x*x + z*z)

y = x*z/(a*a)

y = limit(y, -5, 5)
