Woah, sorry, somehow the body of my post got lost. Let's try again. Thanks for your help!
When I run the following script in Lumerical 2022 R2.3, it runs as expected by creating a new material with Re(index xx) = 2, Re(index yy) = 3, Re(index zz) = 4. However, when I run it in Lumerical 2023 R2.2, it creates a new material with Re(index xx) = 2, Re(index yy) = 2, Re(index zz) = 2. (All imaginary parts are 0 in both cases) Is this a bug or is there a change in how I need to define the index of a diagonal, anisotropic material? Thanks!
permittivity = [c/1e-6, 4+1i*0, 9+1i*0, 16+1i*0]
temp = addmaterial("Sampled 3D data");
setmaterial("TestMat","sampled data", permittivity);