Hello,
Yes, it is possible to display several curves in a plot. Use the multiple_curves_0_2_x branch:
http://qwtplot3d.svn.sourceforge.net/viewvc/qwtplot3d/branches/multiple_curves_0_2_x/
Take a look at the examples in order to see how to add/edit the curves.
I hope this helps and best regards,
Ion Vasilief.
