> I think something is wrong with plot3d and nticks. The following code > should make a nicer curve: > > > plot3d([cos(t), sin(t), t], [t,0,6*%pi], [u,-5,5], [nticks,200])$ Use grid for plot3d: plot3d([sin(t), cos(t), t], [t,-5,5], [y,-5,5], [grid,100,2], [gnuplot_pm3d,false])$ Andrej