I'm trying to obtain an electron density from orbital information written in the Molden format by the formula, $$ \rho(\mathbf{r}) = \sum_{i}^{occ} |\phi_{i}(\mathbf{r})|^{2}. \tag{1} $$
Is there any post-processing program to handle this job?
I believe that I can make a script on my own, because the Molden file seems to provide coefficients of GTO, but want to check if there are already working examples.
It would be desirable that the final density function data is in the format compatible with usual visualization software (such as Molden, VMD, etc.), but I think that it can be visualized if it is represented in a 3D grid.