constants.f90 Source File

module constants

!! This module contains mathematical constants and strings that contain the various directories used by the program.
!!    Math constants:
!!    - PI
!!    - 2 PI
!!    - wp (working precision of the whole program). Default is double precision (64bit floats)
!!    Directories:
!!    - homedir. Root directory of this code
!!    - fileplace. data folder directory
 !!   - resdir. holds the path to the directory that holds the parameter and other associated input files

    use iso_fortran_env, only : real64, real32

    implicit none

    !> current working precision
    integer,           parameter :: wp = real64 !can change this to other precision, not tested for lower or higher precisions.
    !> single precision variable.
    integer,           parameter :: sp = real32
    !> double precision variable.
    integer,           parameter :: dp = real64
    !> \[\pi\]
    real(kind=wp),     parameter :: PI=4._wp*atan(1._wp)
    !> \[2 \pi\]
    real(kind=wp),     parameter :: TWOPI=2._wp*PI
    !> Weight threshold for roulette
    real(kind=wp),     parameter :: THRESHOLD = 0.01_wp
    !> Proportion of packet that survive roulette
    real(kind=wp),     parameter :: CHANCE = 0.1_wp
    !> root directory
    character(len=255)          :: homedir
    !> place where output files are saved
    character(len=255)          :: fileplace
    !> directory to input files
    character(len=255)          :: resdir

end module constants