Rotated equidistant cylindrical grib decoder and grid coordinate transformations. More...

Data Types
type	ip_rot_equid_cylind_egrid

Functions/Subroutines
subroutine	gdswzd_rot_equid_cylind_egrid (self, IOPT, NPTS, FILL, XPTS, YPTS, RLON, RLAT, NRET, CROT, SROT, XLON, XLAT, YLON, YLAT, AREA)
	Calculates Earth coordinates (iopt = 1) or grid coorindates (iopt = -1) for rotated equidistant cylindrical grids. More...

subroutine	init_grib1 (self, g1_desc)
	Initializes a rotated equidistant cylindrical grid given a grib1_descriptor object. More...

subroutine	init_grib2 (self, g2_desc)
	Initializes a rotated equidistant cylindrical grid given a grib2_descriptor object. More...

subroutine	rot_equid_cylind_egrid_error (IOPT, FILL, RLAT, RLON, XPTS, YPTS, NPTS)

subroutine	rot_equid_cylind_egrid_grid_area (FILL, AREA)
	Computes the grid box area for a rotated equidistant cylindrical grid. More...

subroutine	rot_equid_cylind_egrid_map_jacob (FILL, RLON, XLON, XLAT, YLON, YLAT)
	Computes the map jacobians for a rotated equidistant cylindrical grid. More...

subroutine	rot_equid_cylind_egrid_vect_rot (RLON, CROT, SROT)
	Computes the vector rotation sines and cosines for a rotated equidistant cylindrical grid. More...

Variables
real(kind=kd)	clat

real(kind=kd)	clat0

real(kind=kd)	clatr

real(kind=kd)	clon

real(kind=kd)	dlats

real(kind=kd)	dlons

integer	irot

integer, parameter	kd = real64

real(kind=kd)	rerth

real(kind=kd)	rlon0

real(kind=kd)	slat

real(kind=kd)	slat0

real(kind=kd)	slatr

Detailed Description

Rotated equidistant cylindrical grib decoder and grid coordinate transformations.

Author: George Gayno, Mark Iredell, Kyle Gerheiser

Date: July 2021

Function/Subroutine Documentation

◆ gdswzd_rot_equid_cylind_egrid()

subroutine ip_rot_equid_cylind_egrid_mod::gdswzd_rot_equid_cylind_egrid	(	class(ip_rot_equid_cylind_egrid), intent(in)	self,
		integer, intent(in)	IOPT,
		integer, intent(in)	NPTS,
		real, intent(in)	FILL,
		real, dimension(npts), intent(inout)	XPTS,
		real, dimension(npts), intent(inout)	YPTS,
		real, dimension(npts), intent(inout)	RLON,
		real, dimension(npts), intent(inout)	RLAT,
		integer, intent(out)	NRET,
		real, dimension(npts), intent(out), optional	CROT,
		real, dimension(npts), intent(out), optional	SROT,
		real, dimension(npts), intent(out), optional	XLON,
		real, dimension(npts), intent(out), optional	XLAT,
		real, dimension(npts), intent(out), optional	YLON,
		real, dimension(npts), intent(out), optional	YLAT,
		real, dimension(npts), intent(out), optional	AREA
	)

private

Calculates Earth coordinates (iopt = 1) or grid coorindates (iopt = -1) for rotated equidistant cylindrical grids.

Works for e-staggered rotated equidistant cylindrical projections. The scan mode determines whether this is an "h" or "v" grid.

If the selected coordinates are more than one gridpoint beyond the the edges of the grid domain, then the relevant output elements are set to fill values.

The actual number of valid points computed is returned too. Optionally, the vector rotations, the map jacobians and the grid box areas may be returned as well.

To compute the vector rotations, the optional arguments 'srot' and 'crot' must be present.

To compute the map jacobians, the optional arguments 'xlon', 'xlat', 'ylon', 'ylat' must be present.

To compute the grid box areas, the optional argument 'area' must be present.

Parameters

[in]	self	The grid object gdswzd was called on.
[in]	iopt	option flag +1 to compute earth coords of selected grid coords. -1 o compute grid coords of selected earth coords.
[in]	npts	Maximum number of coordinates.
[in]	fill	Fill value to set invalid output data. Must be impossible value; suggested value: -9999.
[in,out]	xpts	Grid x point coordinates if iopt>0.
[in,out]	ypts	Grid y point coordinates if iopt>0.
[in,out]	rlon	Earth longitudes in degrees e if iopt<0 (Acceptable range: -360. to 360.)
[in,out]	rlat	Earth latitudes in degrees n if iopt<0 (Acceptable range: -90. to 90.)
[out]	nret	Number of valid points computed.
[out]	crot	Optional clockwise vector rotation cosines.
[out]	srot	Optional clockwise vector rotation sines.
[out]	xlon	Optional dx/dlon in 1/degrees.
[out]	xlat	Optional dx/dlat in 1/degrees.
[out]	ylon	Optional dy/dlon in 1/degrees.
[out]	ylat	Optional dy/dlat in 1/degrees.
[out]	area	Optional area weights in m**2.

Author: Mark Iredell, George Gayno, Kyle Gerheiser

Date: Jan 2015

Definition at line 229 of file ip_rot_equid_cylind_egrid_mod.f90.

◆ init_grib1()

subroutine ip_rot_equid_cylind_egrid_mod::init_grib1	(	class(ip_rot_equid_cylind_egrid), intent(inout)	self,
		type(grib1_descriptor), intent(in)	g1_desc
	)

private

Initializes a rotated equidistant cylindrical grid given a grib1_descriptor object.

Parameters

[in,out]	self	The grid to initialize
[in]	g1_desc	A grib1_descriptor

Author: Kyle Gerheiser

Date: July 2021

Definition at line 48 of file ip_rot_equid_cylind_egrid_mod.f90.

◆ init_grib2()

subroutine ip_rot_equid_cylind_egrid_mod::init_grib2	(	class(ip_rot_equid_cylind_egrid), intent(inout)	self,
		type(grib2_descriptor), intent(in)	g2_desc
	)

private

Initializes a rotated equidistant cylindrical grid given a grib2_descriptor object.

Parameters

[in,out]	self	The grid to initialize
[in]	g2_desc	A grib2_descriptor

Author: Kyle Gerheiser

Date: July 2021

Definition at line 125 of file ip_rot_equid_cylind_egrid_mod.f90.

◆ rot_equid_cylind_egrid_error()

subroutine ip_rot_equid_cylind_egrid_mod::rot_equid_cylind_egrid_error	(	integer, intent(in)	IOPT,
		real, intent(in)	FILL,
		real, dimension(npts), intent(out)	RLAT,
		real, dimension(npts), intent(out)	RLON,
		real, dimension(npts), intent(out)	XPTS,
		real, dimension(npts), intent(out)	YPTS,
		integer, intent(in)	NPTS
	)

private

Definition at line 423 of file ip_rot_equid_cylind_egrid_mod.f90.

◆ rot_equid_cylind_egrid_grid_area()

subroutine ip_rot_equid_cylind_egrid_mod::rot_equid_cylind_egrid_grid_area	(	real, intent(in)	FILL,
		real, intent(out)	AREA
	)

private

Computes the grid box area for a rotated equidistant cylindrical grid.

Parameters

[in]	fill	Fill value for undefined points.
[out]	area	Area weights in m^2.

Author: George Gayno

Date: Jan 2015

Definition at line 561 of file ip_rot_equid_cylind_egrid_mod.f90.

◆ rot_equid_cylind_egrid_map_jacob()

subroutine ip_rot_equid_cylind_egrid_mod::rot_equid_cylind_egrid_map_jacob	(	real, intent(in)	FILL,
		real, intent(in)	RLON,
		real, intent(out)	XLON,
		real, intent(out)	XLAT,
		real, intent(out)	YLON,
		real, intent(out)	YLAT
	)

private

Computes the map jacobians for a rotated equidistant cylindrical grid.

Parameters

[in]	fill	Fill value for undefined points.
[in]	rlon	Longitude in degrees.
[out]	xlon	dx/dlon in 1/degrees.
[out]	xlat	dx/dlat in 1/degrees.
[out]	ylon	dy/dlon in 1/degrees.
[out]	ylat	dy/dlat in 1/degrees.