I am in real need for a graphical application with 3d plotting capabilities. I need to plot some particles given their space coordinate. This has been well managed using VMD. But i am clueless how to plot associated velocity vector with particles. So basicall i am looking for to plot velocity field. I have already done similar things in 2d with xmgrace. such nice apps. but gnuplot is not good at all for 3d plotting specially the field. My data sets are: for position plot in 3d (x, y, z) for velocity fields in 3d (x, y, z, vx, vy, vz) (it will look like some arrows in space) Any help will be highly sppreciated and i am sad to say that i need suggestion urgently as my report submission date is very close. regards.