Budget interpolation routines for scalars and vectors. More...

Data Types
interface	interpolate_budget

Functions/Subroutines
subroutine	interpolate_budget_scalar (ipopt, grid_in, grid_out, mi, mo, km, ibi, li, gi, no, rlat, rlon, ibo, lo, go, iret)
	Performs budget interpolation from any grid to any grid (or to random station points) for scalar fields.

subroutine	interpolate_budget_vector (ipopt, grid_in, grid_out, mi, mo, km, ibi, li, ui, vi, no, rlat, rlon, crot, srot, ibo, lo, uo, vo, iret)
	This subprogram performs budget interpolation from any grid to any grid (or to random station points) for vector fields.

Detailed Description

Budget interpolation routines for scalars and vectors.

Author: George Gayno, Mark Iredell, Kyle Gerheiser, Eric Engle

Date: July 2021

Function/Subroutine Documentation

◆ interpolate_budget_scalar()

subroutine budget_interp_mod::interpolate_budget_scalar	(	integer, dimension(20), intent(in)	ipopt,
		class(ip_grid), intent(in)	grid_in,
		class(ip_grid), intent(in)	grid_out,
		integer, intent(in)	mi,
		integer, intent(in)	mo,
		integer, intent(in)	km,
		integer, dimension(km), intent(in)	ibi,
		logical*1, dimension(mi,km), intent(in)	li,
		real, dimension(mi,km), intent(in)	gi,
		integer, intent(out)	no,
		real, dimension(mo), intent(inout)	rlat,
		real, dimension(mo), intent(inout)	rlon,
		integer, dimension(km), intent(out)	ibo,
		logical*1, dimension(mo,km), intent(out)	lo,
		real, dimension(mo,km), intent(out)	go,
		integer, intent(out)	iret
	)

private

Performs budget interpolation from any grid to any grid (or to random station points) for scalar fields.

The algorithm simply computes (weighted) averages of bilinearly interpolated points arranged in a square box centered around each output grid point and stretching nearly halfway to each of the neighboring grid points.

Options allow choices of number of points in each radius from the center point (ipopt(1)) which defaults to 2 (if ipopt(1)=-1) meaning that 25 points will be averaged; further options are the respective weights for the radius points starting at the center point (ipopt(2:2+ipopt(1)) which defaults to all 1 (if ipopt(1)=-1 or ipopt(2)=-1).

A special interpolation is done if ipopt(2)=-2. in this case, the boxes stretch nearly all the way to each of the neighboring grid points and the weights are the adjoint of the bilinear interpolation weights. This case gives quasi-second-order budget interpolation.

Another option is the minimum percentage for mask, i.e. percent valid input data required to make output data, (ipopt(3+ipopt(1)) which defaults to 50 (if -1).

In cases where there is no or insufficient valid input data, the user may choose to search for the nearest valid data. this is invoked by setting ipopt(20) to the width of the search square. The default is 1 (no search). Squares are searched for valid data in a spiral pattern starting from the center. No searching is done where the output grid is outside the input grid.

Only horizontal interpolation is performed.

Parameters

[in]	ipopt	Interpolation options ipopt(1) is number of radius points (defaults to 2 if ipopt(1)=-1). ipopt(2:2+ipopt(1)) are respective weights (defaults to all 1 if ipopt(1)=-1 or ipopt(2)=-1). ipopt(3+ipopt(1)) is minimum percentage for mask (defaults to 50 if ipopt(3+ipopt(1)=-1).
[in]	grid_in	Input grid
[in]	grid_out	Output grid
[in]	mi	Skip number between input grid fields if km>1 or dimension of input grid fields if km=1.
[out]	mo	Skip number between output grid fields if km>1 or dimension of output grid fields if km=1.
[in]	km	Number of fields to interpolate.
[in]	ibi	Input bitmap flags.
[in]	li	Input bitmaps (if some ibi(k)=1).
[in]	gi	Input fields to interpolate.
[in,out]	no	Number of output points (only if igdtnumo<0).
[in,out]	rlat	Output latitudes in degrees (if igdtnumo<0).
[in,out]	rlon	Output longitudes in degrees (if igdtnumo<0).
[out]	ibo	Output bitmap flags.
[out]	lo	Output bitmaps (always output).
[out]	go	Output fields interpolated.
[out]	iret	Return code. 0 Successful interpolation. 2 Unrecognized input grid or no grid overlap. 3 Unrecognized output grid. 32 Invalid budget method parameters.

Author: Marke Iredell, George Gayno, Kyle Gerheiser, Eric Engle

Date: July 2021

Definition at line 94 of file budget_interp_mod.F90.

◆ interpolate_budget_vector()

subroutine budget_interp_mod::interpolate_budget_vector	(	integer, dimension(20), intent(in)	ipopt,
		class(ip_grid), intent(in)	grid_in,
		class(ip_grid), intent(in)	grid_out,
		integer, intent(in)	mi,
		integer, intent(in)	mo,
		integer, intent(in)	km,
		integer, dimension(km), intent(in)	ibi,
		logical*1, dimension(mi,km), intent(in)	li,
		real, dimension(mi,km), intent(in)	ui,
		real, dimension(mi,km), intent(in)	vi,
		integer, intent(out)	no,
		real, dimension(mo), intent(inout)	rlat,
		real, dimension(mo), intent(inout)	rlon,
		real, dimension(mo), intent(out)	crot,
		real, dimension(mo), intent(out)	srot,
		integer, dimension(km), intent(out)	ibo,
		logical*1, dimension(mo,km), intent(out)	lo,
		real, dimension(mo,km), intent(out)	uo,
		real, dimension(mo,km), intent(out)	vo,
		integer, intent(out)	iret
	)