horiz_interp_bilinear.F90

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!> @defgroup horiz_interp_bilinear_mod horiz_interp_bilinear_mod
!> @ingroup horiz_interp
!> @brief Performs spatial interpolation between grids using bilinear interpolation
!!
!> @author Zhi Liang <Zhi.Liang@noaa.gov>
!> This module can interpolate data from regular rectangular grid
!! to rectangular/tripolar grid. The interpolation scheme is bilinear interpolation.
!! There is an optional mask field for missing input data.
!! An optional output mask field may be used in conjunction with
!! the input mask to show where output data exists.
 
module horiz_interp_bilinear_mod
 
  use mpp_mod,               only: mpp_error, fatal, stdout, mpp_pe, mpp_root_pe
  use fms_mod,               only: write_version_number
  use constants_mod,         only: pi
  use horiz_interp_type_mod, only: horiz_interp_type, stats, bilinear
  use platform_mod,          only: r4_kind, r8_kind
  use axis_utils2_mod,       only: nearest_index
  use fms2_io_mod,           only: open_file, close_file, read_data, fmsnetcdffile_t, get_dimension_size
  use fms_string_utils_mod,  only: string
 
  implicit none
  private
 
 
  public :: horiz_interp_bilinear_new, horiz_interp_bilinear, horiz_interp_bilinear_del
  public :: horiz_interp_bilinear_init, horiz_interp_read_weights_bilinear
 
  !> Creates a @ref horiz_interp_type for bilinear interpolation.
  !> @ingroup horiz_interp_bilinear_mod
  interface horiz_interp_bilinear_new
    module procedure horiz_interp_bilinear_new_1d_r4
    module procedure horiz_interp_bilinear_new_1d_r8
    module procedure horiz_interp_bilinear_new_2d_r4
    module procedure horiz_interp_bilinear_new_2d_r8
  end interface
 
  !> Subroutines for reading in weight files and using that to fill in the horiz_interp type instead
  !! calculating it
  !> @ingroup horiz_interp_bilinear_mod
  interface horiz_interp_read_weights_bilinear
    module procedure horiz_interp_read_weights_bilinear_r4
    module procedure horiz_interp_read_weights_bilinear_r8
  end interface
 
  interface horiz_interp_bilinear
    module procedure horiz_interp_bilinear_r4
    module procedure horiz_interp_bilinear_r8
  end interface
 
!> @addtogroup horiz_interp_bilinear_mod
!> @{
 
  real(r8_kind), parameter :: epsln=1.e-10_r8_kind
  real(r4_kind), parameter :: epsln_r4=1.e-4_r4_kind
  integer, parameter :: DUMMY = -999
 
!! Private helper routines, interfaces for mixed real precision support
  interface intersect
    module procedure intersect_r4
    module procedure intersect_r8
  end interface
 
  !-----------------------------------------------------------------------
! Include variable "version" to be written to log file.
#include<file_version.h>
  logical            :: module_is_initialized = .false.
 
contains
 
  !> Initialize this module and writes version number to logfile.
  subroutine horiz_interp_bilinear_init
 
    if(module_is_initialized) return
    call write_version_number("HORIZ_INTERP_BILINEAR_MOD", version)
    module_is_initialized = .true.
 
  end subroutine horiz_interp_bilinear_init
 
  !> @brief Deallocates memory used by "horiz_interp_type" variables.
  !!
  !> Must be called before reinitializing with horiz_interp_bilinear_new.
  subroutine horiz_interp_bilinear_del( Interp )
 
    type (horiz_interp_type), intent(inout) :: interp!< A derived-type variable returned by previous
                                   !! call to horiz_interp_bilinear_new. The input variable must
                                   !! have allocated arrays. The returned variable will contain
                                   !! deallocated arrays
 
    if( interp%horizInterpReals4_type%is_allocated) then
      if(allocated(interp%horizInterpReals4_type%wti))   deallocate(interp%horizInterpReals4_type%wti)
      if(allocated(interp%horizInterpReals4_type%wtj))   deallocate(interp%horizInterpReals4_type%wtj)
    else if (interp%horizInterpReals8_type%is_allocated) then
      if(allocated(interp%horizInterpReals8_type%wti))   deallocate(interp%horizInterpReals8_type%wti)
      if(allocated(interp%horizInterpReals8_type%wtj))   deallocate(interp%horizInterpReals8_type%wtj)
    endif
    if(allocated(interp%i_lon)) deallocate(interp%i_lon)
    if(allocated(interp%j_lat)) deallocate(interp%j_lat)
 
    interp%horizInterpReals4_type%is_allocated = .false.
    interp%horizInterpReals8_type%is_allocated = .false.
 
  end subroutine horiz_interp_bilinear_del
 
#include "horiz_interp_bilinear_r4.fh"
#include "horiz_interp_bilinear_r8.fh"
 
end module horiz_interp_bilinear_mod
!> @}
! close documentation grouping