Show isosurface from data in a CSV file

I have a csv file. The first three columns are x,y,z coordinates and the fourth column is a density value between 0.0 and 1.0. I just want to plot an isosurface through these density values using a prescribed critical density, say 0.5.

I know this should be simple and someone probably has a tutorial on that, but I have been reading and reading different websites and paraview support and I can’t find it. I can read the csv file and display the table as points filter, etc. I also know that isosurfaces are obtained using Filter->Contour, but the contour filter is disabled when I try to select it.

I’m truly sorry to waste anyone’s time on a simple question, but I’ve been reading tutorials for hours and not finding anything. Help is truly appreciated!

  • File → Open → file.csv, Apply
  • TableToStructuredGrid, Apply
  • Contour, Apply