Tested with nag compiler

[hassaniriad]

Hi Stefano,
First of all, thank you for this great and very useful library.

As I saw that VTKFortran has not been tested with nagfor and there may be people interested, I would like to inform you that it works perfectly with one small detail: nagfor complains about the selected_real_kind(33,4931) value of the R16P parameter (penf_global_parameters_variables module): "...does not specify a valid representation method".

I replaced it with selected_real_kind(31,291) (maybe real128 from iso_fortran_env would be better?) and everything works fine.
Regards,
Riad