55 lines
1.9 KiB
Fortran
55 lines
1.9 KiB
Fortran
!!******************************************************************************
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!!
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!! This file is part of the AMUN source code, a program to perform
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!! Newtonian or relativistic magnetohydrodynamical simulations on uniform or
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!! adaptive mesh.
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!!
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!! Copyright (C) 2008-2024 Grzegorz Kowal <grzegorz@amuncode.org>
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!!
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!! This program is free software: you can redistribute it and/or modify
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!! it under the terms of the GNU General Public License as published by
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!! the Free Software Foundation, either version 3 of the License, or
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!! (at your option) any later version.
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!!
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!! This program is distributed in the hope that it will be useful,
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!! but WITHOUT ANY WARRANTY; without even the implied warranty of
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!! MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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!! GNU General Public License for more details.
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!!
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!! You should have received a copy of the GNU General Public License
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!! along with this program. If not, see <http://www.gnu.org/licenses/>.
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!!
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!!*****************************************************************************
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!!
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!! module: CONSTANTS
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!!
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!! This module provides mathematical, physical, and unit conversion
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!! constants and factors.
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!!
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!!*****************************************************************************
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!
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module constants
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implicit none
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! π and its multiplications
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!
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real(kind=8), parameter :: pi = 3.14159265358979323846264338327950d+00
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real(kind=8), parameter :: pi2 = 6.28318530717958647692528676655900d+00
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real(kind=8), parameter :: pi4 = 1.25663706143591729538505735331180d+01
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! exp(-1/2)
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!
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real(kind=8), parameter :: ehi = 0.60653065971263342360379953499118d+00
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! conversion between angular units (degree to radian and radian to degree)
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!
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real(kind=8), parameter :: d2r = 1.74532925199432954743716805978693d-02
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real(kind=8), parameter :: r2d = 5.72957795130823228646477218717337d+01
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public
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!===============================================================================
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!
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end module constants
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