Trans_t Struct Reference

Struct that holds information to do transforms for one particular grid resolution. More...

#include <transi.h>

Public Attributes
INPUT
int	ndgl
	Number of lattitudes.
int *	nloen
	Number of longitude points for each latitude DIMENSIONS(1:NDGL)
int	nlon
	Number of longitude points for all latitudes .
int	nsmax
	Spectral truncation wave number.
_bool	lsplit
	If false, the distribution does not allow latitudes to be split.
int	llatlon
	If true, the transforms compute extra coefficients for latlon transforms.
int	flt
	If true, the Fast-Legendre-Transform method is used which is faster for higher resolutions (N1024)
int	fft
	FFT library to use underneith FFT992 = 1 ; FFTW = 2.
char *	readfp
char *	writefp
const void *	cache
size_t	cachesize
PARALLELISATION
int	myproc
	Current MPI task (numbering starting at 1)
int	nproc
	Number of parallel MPI tasks.
MULTI-TRANSFORMS-MANAGEMENT
int	handle
	Resolution tag for which info is required ,default is the first defined resulution (input)
_bool	ldlam
	True if the corresponding resolution is LAM, false if it is global.
SPECTRAL SPACE
int	nspec
	Number of complex spectral coefficients on this PE.
int	nspec2
	Number of complex spectral coefficients on this PE times 2 (real and imag)
int	nspec2g
	global KSPEC2
int	nspec2mx
	Maximun KSPEC2 among all PEs.
int	nump
	Number of spectral waves handled by this PE.
int	ngptot
	Total number of grid columns on this PE.
int	ngptotg
	Total number of grid columns on the Globe.
int	ngptotmx
	Maximum number of grid columns on any of the PEs.
int *	ngptotl
	Number of grid columns on each PE DIMENSIONS(1:N_REGIONS_NS,1:N_REGIONS_EW)
int *	nmyms
	This PEs spectral zonal wavenumbers DIMENSIONS(1:NUMP)
int *	nasm0
	Address in a spectral array of (m, n=m) DIMENSIONS(0:NSMAX)
int	nprtrw
	Number of processors in A-direction (input)
int *	numpp
	No. of wave numbers each wave set is responsible for. DIMENSIONS(1:NPRTRW)
int *	npossp
	Defines partitioning of global spectral fields among PEs DIMENSIONS(1:NPRTRW+1)
int *	nptrms
	Pointer to the first wave number of a given a-set DIMENSIONS(1:NPRTRW)
int *	nallms
	Wave numbers for all wave-set concatenated together to give all wave numbers in wave-set order DIMENSIONS(1:NSMAX+1)
int *	ndim0g
	Defines partitioning of global spectral fields among PEs DIMENSIONS(0:NSMAX)
int *	nvalue
	n value for each KSPEC2 spectral coeffient DIMENSIONS(1:NSPEC2)
GRIDPOINT SPACE
int	n_regions_NS
	Number of regions in North-South direction.
int	n_regions_EW
	Number of regions in East-West direction.
int	my_region_NS
	My region in North-South direction.
int	my_region_EW
	My region in East-West direction.
int *	n_regions
	Number of East-West Regions per band of North-South Regions.
int *	nfrstlat
	First latitude of each a-set in grid-point space DIMENSIONS(1:N_REGIONS_NS)
int *	nlstlat
	Last latitude of each a-set in grid-point space DIMENSIONS(1:N_REGIONS_NS)
int	nfrstloff
	Offset for first lat of own a-set in grid-point space.
int *	nptrlat
	Pointer to the start of each latitude DIMENSIONS(1:NDGL)
int *	nptrfrstlat
	Pointer to the first latitude of each a-set in NSTA and NONL arrays DIMENSIONS(1:N_REGIONS_NS)
int *	nptrlstlat
	Pointer to the last latitude of each a-set in NSTA and NONL arrays DIMENSIONS(1:N_REGIONS_NS)
int	nptrfloff
	Offset for pointer to the first latitude of own a-set NSTA and NONL arrays, i.e. nptrfrstlat(myseta)-1.
int *	nsta
	Position of first grid column for the latitudes on a processor. DIMENSIONS(1:NDGL+N_REGIONS_NS-1,1:N_REGIONS_EW)
int *	nonl
	Number of grid columns for the latitudes on a processor. Similar to nsta() in data structure. DIMENSIONS(1:NDGL+N_REGIONS_NS-1,1:N_REGIONS_EW)
_bool *	ldsplitlat
	True if latitude is split in grid point space over two a-sets. DIMENSIONS(1:NDGL)
FOURIER SPACE
int	nprtrns
	No. of sets in N-S direction (Fourier space) (always equal to NPRTRW)
int *	nultpp
	Number of latitudes for which each a-set is calculating the FFT's. DIMENSIONS(1:NPRTRNS)
int *	nptrls
	Pointer to first global latitude of each a-set for which it performs the Fourier calculations DIMENSIONS(1:NPRTRNS)
int *	nnmeng
	associated (with NLOENG) cut-off zonal wavenumber DIMENSIONS(1:NDGL)
LEGENDRE
double *	rmu
	sin(Gaussian latitudes) DIMENSIONS(1:NDGL)
double *	rgw
	Gaussian weights DIMENSIONS(1:NDGL)
double *	rpnm
	Legendre polynomials DIMENSIONS(1:NLEI3,1:NSPOLEGL)
int	nlei3
	First dimension of Legendre polynomials.
int	nspolegl
	Second dimension of Legendre polynomials.
int *	npms
	Adress for legendre polynomial for given M (NSMAX) DIMENSIONS(0:NSMAX)
double *	rlapin
	Eigen-values of the inverse Laplace operator DIMENSIONS(-1:NSMAX+2)
int *	ndglu
	Number of active points in an hemisphere for a given wavenumber "m" DIMENSIONS(0:NSMAX)

Detailed Description

Struct that holds information to do transforms for one particular grid resolution.

The values ndgl, nloen, and nsmax need to be provided yourself, all other values will be defined during the trans_setup() call or trans_inquire() calls

• All scalar values will be defined by trans_setup()
• All array values will be allocated if needed, and defined by individual calls to trans_inquire()

Note

Many of these values are of no interest for normal usage

Member Data Documentation

n_regions

int* Trans_t::n_regions

Number of East-West Regions per band of North-South Regions.

DIMENSIONS(1:N_REGIONS_NS)

nsta

int* Trans_t::nsta

Position of first grid column for the latitudes on a processor.
DIMENSIONS(1:NDGL+N_REGIONS_NS-1,1:N_REGIONS_EW)

The information is available for all processors. The b-sets are distinguished by the last dimension of nsta(). The latitude band for each a-set is addressed by nptrfrstlat(jaset),nptrlstlat(jaset), and nptrfloff=nptrfrstlat(myseta) on this processors a-set. Each split latitude has two entries in nsta(,:) which necessitates the rather complex addressing of nsta(,:) and the overdimensioning of nsta by N_REGIONS_NS.

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The documentation for this struct was generated from the following file:

• /Users/samhatfield/Work/ECMWF/ectrans/src/transi/transi.h