Problem with contour plot of calculator in Paraview
 

Dear Foamers,

I've calculated stress tensor data with my Paraview calculator. Plotting the data in a line chart works perfectly fine. However, when I make a contour plot, only the absolute values of the data are displayed. For clarity, there are no components to choose from (in other words, no magnitude component). Any ideas on how to fix this?

Many thanks in advance.