!> Physical/mathematical constants shared across the library: \( \pi \) !> and the imaginary unit \( i \), both at [[KINDS:dp]] precision so every !> expression built from them (spherical harmonics, VSH, coupling !> coefficients) stays in double precision without repeated literal !> casts. MODULE GLOBALS USE KINDS, ONLY: dp IMPLICIT NONE PRIVATE PUBLIC :: pi, j !> \( \pi \), double precision. REAL(KIND=dp), PARAMETER :: pi=3.14159265358979324d0 !> Imaginary unit \( i=\sqrt{-1} \), double-precision complex. COMPLEX(KIND=dp), PARAMETER :: j = (0,1) END MODULE GLOBALS