> For something focused on numerics, it's lacking in standard IEEE numerical things such as a function to check for nan (GNU extension?!) The IEEE_ARITHMETIC m

> For something focused on numerics, it's lacking in standard IEEE numerical things such as a function to check for nan (GNU extension?!) The IEEE_ARITHMETIC module has been part of the Fortran standard since Fortran 2003, and includes, among others, the IEEE_IS_NAN() function. (Supported in GFortran since version 5: https://gcc.gnu.org/gcc-5/changes.html https://gcc.gnu.org/gcc-5/changes.html)