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I'm currently running a CFD simulation for an internal flow and need to compare my computed results to experimental data. The experimental data is saved as a comma separated file with columns for x,y,z coordinates and pressure. The computed data is saved in Ensight format on an unstructured 3D mesh.

As an example, I have the following experimental data:




I would like to plot the pressure along the y-axis at x=-0.08573 as a function of z, and overlay crosshairs to show the experimental data. I can create the two plots separately, using the "Plot Over Line" filter for the CFD data, and the "Plot Data" filter for the experimental data.

I have tried using the "Group Datasets" filter to combine the two sources, but when I try to plot I run into problems.

If I use "Plot Over Line", the experimental data doesn't show in the plot. I think this is due to rounding in the coordinates for the line vs. the data.

If I use "Plot Data", I can get both to show up, but only if I set the X axis data to "Use Array Index From Y Axis Data". When I do this, the experimental data aren't plotted over the correct part of the CFD data. Switching to "Use Data Array" and Points(2) for the z-coordinates, I get an error "No X column is set (index 0)."

This seems like it should be a simple thing to accomplish, and a fairly common task, but I've had no luck finding a tutorial or explanation online. I know that I can just export the data and use gnuplot or xmgrace, but I would rather do all the processing in one program if possible.

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