!-----------------------------------------------------------------------------------------------------------------------------------
! This file is part of ReMKiT1D.
!
! ReMKiT1D is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as
! published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
!
! ReMKiT1D is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
! MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
!
! You should have received a copy of the GNU General Public License along with ReMKiT1D. If not, see <https://www.gnu.org/licenses/>.
!
! Copyright 2023 United Kingdom Atomic Energy Authority (stefan.mijin@ukaea.uk)
!-----------------------------------------------------------------------------------------------------------------------------------
module interpolation_derivation_class
!! author: Stefan Mijin
!!
!! Houses derivation that interpolates one quantity from the original to the dual grid or vice versa.
use data_kinds ,only: rk ,ik
use runtime_constants ,only: debugging, assertions
use assertion_utility ,only: assert, assertIdentical, assertPure
use god_objects ,only: Object
use support_types ,only: RealArray
use derivation_abstract_class ,only: Derivation
use geometry_class ,only: Geometry
use grid_class ,only: Grid
implicit none
private
type ,public ,extends(Derivation) :: InterpolationDerivation
!! Derivation that interpolates a variable from the original to the dual grid, or vise versa. Distributions are interpolated
!! by assuming that even l harmonics live on the original grid and odd harmonics on the dual grid.
real(rk) ,allocatable ,dimension(:) ,private :: linInterp !! Linear interpolation coefficients for inner points
real(rk) ,allocatable ,dimension(:) ,private :: linInterpDual !! Linear interpolation coefficients for inner points on dual grid
real(rk) ,private :: linExterp !! Linear extrapolation coefficients for the right boundary point
real(rk) ,private :: linExterpRDual !! Linear extrapolation coefficient for the right boundary point during inverse interpolation on non-periodic grid
real(rk) ,private :: linExterpLDual !! Linear extrapolation coefficient for the left boundary point during inverse interpolation on non-periodic grid
logical ,private :: periodicGrid
logical ,private :: inverseInterp !! True if interpolating from dual to original grid. Defaults to false
logical ,private :: distInterp !! True if interpolating a distribution function
logical ,private :: containsLeftBoundary !! True if the local x-grid contains the left boundary
logical ,private :: containsRightBoundary !! True if the local x-grid contains the right boundary
integer(ik) ,private :: locNumX !! Size of local grid chunk (without any halos)
integer(ik) ,private :: numV
integer(ik) ,private :: numH
logical(ik) ,allocatable ,dimension(:) :: oddHarmonic !! True for odd l harmonics
contains
procedure ,public :: init => initInterpDeriv
procedure ,public :: calculate => calculateInterp
end type InterpolationDerivation
!-----------------------------------------------------------------------------------------------------------------------------------
interface
!-----------------------------------------------------------------------------------------------------------------------------------
module subroutine initInterpDeriv(this,geometryObj,gridObj,minX,maxX,inverseInterp,distInterp)
!! Initialize interpolation derivation object
class(InterpolationDerivation) ,intent(inout) :: this
type(Geometry) ,intent(in) :: geometryObj
type(Grid) ,intent(in) :: gridObj
integer(ik) ,intent(in) :: minX
integer(ik) ,intent(in) :: maxX
logical ,optional ,intent(in) :: inverseInterp
logical ,optional ,intent(in) :: distInterp
end subroutine initInterpDeriv
!-----------------------------------------------------------------------------------------------------------------------------------
module function calculateInterp(this,inputArray,indices) result(output)
class(InterpolationDerivation) ,intent(inout) :: this
type(RealArray) ,dimension(:) ,intent(in) :: inputArray
integer(ik) ,dimension(:) ,intent(in) :: indices
real(rk) ,allocatable ,dimension(:) :: output
end function calculateInterp
!-----------------------------------------------------------------------------------------------------------------------------------
end interface
!-----------------------------------------------------------------------------------------------------------------------------------
end module interpolation_derivation_class
!-----------------------------------------------------------------------------------------------------------------------------------
