WriteMemSize Subroutine

    subroutine WriteMemSize(iunit, MemSize)
        ! Write out a human-readable amount of memory.  MemSize is in bytes.
        integer, intent(in) :: iunit
        integer(int64), intent(in) :: MemSize
        character(len=*), parameter :: fmt1 = '(f6.1, a2)'
        character(len=*), parameter :: fmt2 = '(i7, a1)'
        if (MemUnitsBytes) then
            if (MemSize < 1024_int64**2) then
                ! output in KB.
                write (iunit, fmt1) real(MemSize, dp) / 1024._dp, 'KB'
            else if (MemSize < 1024_int64**3) then
                ! output in MB.
                write (iunit, fmt1) real(MemSize, dp) / 1024._dp**2, 'MB'
            else if (MemSize < 1024_int64**4) then
                ! output in GB.
                write (iunit, fmt1) real(MemSize, dp) / 1024._dp**3, 'GB'
            else if (MemSize < 1024_int64**5) then
                ! output in GB.
                write (iunit, fmt1) real(MemSize, dp) / 1024._dp**4, 'TB'
            else
                write (iunit, '(A)') '> 1 PB'
            end if
        else
            write (iunit, fmt2) MemSize / 8, 'W'
        end if
    end subroutine WriteMemSize