First of all, let me apologize if this is the wrong section to post to. I am in need of ideas on how to visualize a large dataset. I have a dataset (~4GB) of x,y,z,f(x,y,z) values. To best be able to draw conclusions from my data, it must be plotted in such a way that at each x,y,z there is a 3d sphere that has opacity scaled by f(x,y,z). I have tried a couple plotting programs: VisIt, and ParaView. I was not able to get either to provide the functionality I need, although they are very close! I then wrote a python script that created a VTK file with each individual point defined. Yet, the vtk file turned out to be pretty large and there was no viewer capable of displaying it. Any suggestion would be greatly appreciated. I am just looking for some ideas here, I've about ran out.