DAMASK_EICMD/src/quaternions.f90

421 lines
14 KiB
Fortran

! ###################################################################
! Copyright (c) 2013-2015, Marc De Graef/Carnegie Mellon University
! Modified 2017-2019, Martin Diehl/Max-Planck-Institut für Eisenforschung GmbH
! All rights reserved.
!
! Redistribution and use in source and binary forms, with or without modification, are
! permitted provided that the following conditions are met:
!
! - Redistributions of source code must retain the above copyright notice, this list
! of conditions and the following disclaimer.
! - Redistributions in binary form must reproduce the above copyright notice, this
! list of conditions and the following disclaimer in the documentation and/or
! other materials provided with the distribution.
! - Neither the names of Marc De Graef, Carnegie Mellon University nor the names
! of its contributors may be used to endorse or promote products derived from
! this software without specific prior written permission.
!
! THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
! AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
! IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
! ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
! LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
! DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
! SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
! CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
! OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
! USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
! ###################################################################
!---------------------------------------------------------------------------------------------------
!> @author Marc De Graef, Carnegie Mellon University
!> @author Martin Diehl, Max-Planck-Institut für Eisenforschung GmbH
!> @brief general quaternion math, not limited to unit quaternions
!> @details w is the real part, (x, y, z) are the imaginary parts.
!---------------------------------------------------------------------------------------------------
module quaternions
use prec
use future
implicit none
public
real(pReal), parameter, public :: P = -1.0_pReal !< parameter for orientation conversion.
type, public :: quaternion
real(pReal) :: w = 0.0_pReal
real(pReal) :: x = 0.0_pReal
real(pReal) :: y = 0.0_pReal
real(pReal) :: z = 0.0_pReal
contains
procedure, private :: add__
procedure, private :: pos__
generic, public :: operator(+) => add__,pos__
procedure, private :: sub__
procedure, private :: neg__
generic, public :: operator(-) => sub__,neg__
procedure, private :: mul_quat__
procedure, private :: mul_scal__
generic, public :: operator(*) => mul_quat__, mul_scal__
procedure, private :: div_quat__
procedure, private :: div_scal__
generic, public :: operator(/) => div_quat__, div_scal__
procedure, private :: eq__
generic, public :: operator(==) => eq__
procedure, private :: neq__
generic, public :: operator(/=) => neq__
procedure, private :: pow_quat__
procedure, private :: pow_scal__
generic, public :: operator(**) => pow_quat__, pow_scal__
procedure, public :: abs__
procedure, public :: dot_product__
procedure, public :: conjg__
procedure, public :: exp__
procedure, public :: log__
procedure, public :: homomorphed => quat_homomorphed
end type
interface assignment (=)
module procedure assign_quat__
module procedure assign_vec__
end interface assignment (=)
interface quaternion
module procedure init__
end interface quaternion
interface abs
procedure abs__
end interface abs
interface dot_product
procedure dot_product__
end interface dot_product
interface conjg
module procedure conjg__
end interface conjg
interface exp
module procedure exp__
end interface exp
interface log
module procedure log__
end interface log
contains
!---------------------------------------------------------------------------------------------------
!> constructor for a quaternion from a 4-vector
!---------------------------------------------------------------------------------------------------
type(quaternion) pure function init__(array)
real(pReal), intent(in), dimension(4) :: array
init__%w=array(1)
init__%x=array(2)
init__%y=array(3)
init__%z=array(4)
end function init__
!---------------------------------------------------------------------------------------------------
!> assing a quaternion
!---------------------------------------------------------------------------------------------------
elemental subroutine assign_quat__(self,other)
type(quaternion), intent(out) :: self
type(quaternion), intent(in) :: other
self%w = other%w
self%x = other%x
self%y = other%y
self%z = other%z
end subroutine assign_quat__
!---------------------------------------------------------------------------------------------------
!> assing a 4-vector
!---------------------------------------------------------------------------------------------------
pure subroutine assign_vec__(self,other)
type(quaternion), intent(out) :: self
real(pReal), intent(in), dimension(4) :: other
self%w = other(1)
self%x = other(2)
self%y = other(3)
self%z = other(4)
end subroutine assign_vec__
!---------------------------------------------------------------------------------------------------
!> addition of two quaternions
!---------------------------------------------------------------------------------------------------
type(quaternion) elemental function add__(self,other)
class(quaternion), intent(in) :: self,other
add__%w = self%w + other%w
add__%x = self%x + other%x
add__%y = self%y + other%y
add__%z = self%z + other%z
end function add__
!---------------------------------------------------------------------------------------------------
!> unary positive operator
!---------------------------------------------------------------------------------------------------
type(quaternion) elemental function pos__(self)
class(quaternion), intent(in) :: self
pos__%w = self%w
pos__%x = self%x
pos__%y = self%y
pos__%z = self%z
end function pos__
!---------------------------------------------------------------------------------------------------
!> subtraction of two quaternions
!---------------------------------------------------------------------------------------------------
type(quaternion) elemental function sub__(self,other)
class(quaternion), intent(in) :: self,other
sub__%w = self%w - other%w
sub__%x = self%x - other%x
sub__%y = self%y - other%y
sub__%z = self%z - other%z
end function sub__
!---------------------------------------------------------------------------------------------------
!> unary positive operator
!---------------------------------------------------------------------------------------------------
type(quaternion) elemental function neg__(self)
class(quaternion), intent(in) :: self
neg__%w = -self%w
neg__%x = -self%x
neg__%y = -self%y
neg__%z = -self%z
end function neg__
!---------------------------------------------------------------------------------------------------
!> multiplication of two quaternions
!---------------------------------------------------------------------------------------------------
type(quaternion) elemental function mul_quat__(self,other)
class(quaternion), intent(in) :: self, other
mul_quat__%w = self%w*other%w - self%x*other%x - self%y*other%y - self%z*other%z
mul_quat__%x = self%w*other%x + self%x*other%w + P * (self%y*other%z - self%z*other%y)
mul_quat__%y = self%w*other%y + self%y*other%w + P * (self%z*other%x - self%x*other%z)
mul_quat__%z = self%w*other%z + self%z*other%w + P * (self%x*other%y - self%y*other%x)
end function mul_quat__
!---------------------------------------------------------------------------------------------------
!> multiplication of quaternions with scalar
!---------------------------------------------------------------------------------------------------
type(quaternion) elemental function mul_scal__(self,scal)
class(quaternion), intent(in) :: self
real(pReal), intent(in) :: scal
mul_scal__%w = self%w*scal
mul_scal__%x = self%x*scal
mul_scal__%y = self%y*scal
mul_scal__%z = self%z*scal
end function mul_scal__
!---------------------------------------------------------------------------------------------------
!> division of two quaternions
!---------------------------------------------------------------------------------------------------
type(quaternion) elemental function div_quat__(self,other)
class(quaternion), intent(in) :: self, other
div_quat__ = self * (conjg(other)/(abs(other)**2.0_pReal))
end function div_quat__
!---------------------------------------------------------------------------------------------------
!> divisiont of quaternions by scalar
!---------------------------------------------------------------------------------------------------
type(quaternion) elemental function div_scal__(self,scal)
class(quaternion), intent(in) :: self
real(pReal), intent(in) :: scal
div_scal__ = [self%w,self%x,self%y,self%z]/scal
end function div_scal__
!---------------------------------------------------------------------------------------------------
!> equality of two quaternions
!---------------------------------------------------------------------------------------------------
logical elemental function eq__(self,other)
class(quaternion), intent(in) :: self,other
eq__ = all(dEq([ self%w, self%x, self%y, self%z], &
[other%w,other%x,other%y,other%z]))
end function eq__
!---------------------------------------------------------------------------------------------------
!> inequality of two quaternions
!---------------------------------------------------------------------------------------------------
logical elemental function neq__(self,other)
class(quaternion), intent(in) :: self,other
neq__ = .not. self%eq__(other)
end function neq__
!---------------------------------------------------------------------------------------------------
!> quaternion to the power of a scalar
!---------------------------------------------------------------------------------------------------
type(quaternion) elemental function pow_scal__(self,expon)
class(quaternion), intent(in) :: self
real(pReal), intent(in) :: expon
pow_scal__ = exp(log(self)*expon)
end function pow_scal__
!---------------------------------------------------------------------------------------------------
!> quaternion to the power of a quaternion
!---------------------------------------------------------------------------------------------------
type(quaternion) elemental function pow_quat__(self,expon)
class(quaternion), intent(in) :: self
type(quaternion), intent(in) :: expon
pow_quat__ = exp(log(self)*expon)
end function pow_quat__
!---------------------------------------------------------------------------------------------------
!> exponential of a quaternion
!> ToDo: Lacks any check for invalid operations
!---------------------------------------------------------------------------------------------------
type(quaternion) elemental function exp__(self)
class(quaternion), intent(in) :: self
real(pReal) :: absImag
absImag = norm2([self%x, self%y, self%z])
exp__ = exp(self%w) * [ cos(absImag), &
self%x/absImag * sin(absImag), &
self%y/absImag * sin(absImag), &
self%z/absImag * sin(absImag)]
end function exp__
!---------------------------------------------------------------------------------------------------
!> logarithm of a quaternion
!> ToDo: Lacks any check for invalid operations
!---------------------------------------------------------------------------------------------------
type(quaternion) elemental function log__(self)
class(quaternion), intent(in) :: self
real(pReal) :: absImag
absImag = norm2([self%x, self%y, self%z])
log__ = [log(abs(self)), &
self%x/absImag * acos(self%w/abs(self)), &
self%y/absImag * acos(self%w/abs(self)), &
self%z/absImag * acos(self%w/abs(self))]
end function log__
!---------------------------------------------------------------------------------------------------
!> norm of a quaternion
!---------------------------------------------------------------------------------------------------
real(pReal) elemental function abs__(a)
class(quaternion), intent(in) :: a
abs__ = norm2([a%w,a%x,a%y,a%z])
end function abs__
!---------------------------------------------------------------------------------------------------
!> dot product of two quaternions
!---------------------------------------------------------------------------------------------------
real(pReal) elemental function dot_product__(a,b)
class(quaternion), intent(in) :: a,b
dot_product__ = a%w*b%w + a%x*b%x + a%y*b%y + a%z*b%z
end function dot_product__
!---------------------------------------------------------------------------------------------------
!> conjugate complex of a quaternion
!---------------------------------------------------------------------------------------------------
type(quaternion) elemental function conjg__(a)
class(quaternion), intent(in) :: a
conjg__ = quaternion([a%w, -a%x, -a%y, -a%z])
end function conjg__
!---------------------------------------------------------------------------------------------------
!> homomorphed quaternion of a quaternion
!---------------------------------------------------------------------------------------------------
type(quaternion) elemental function quat_homomorphed(a)
class(quaternion), intent(in) :: a
quat_homomorphed = quaternion(-[a%w,a%x,a%y,a%z])
end function quat_homomorphed
end module quaternions