NAME
Grid_pfftInit
SYNOPSIS
Grid_pfftInit(integer(IN) :: ndim,
logical(IN) :: needMap
integer(IN) :: globalLen(MDIM),
integer(OUT) :: localArraySize(MDIM),
integer(IN),optional :: transformType(MDIM),
integer(IN),optional :: baseDatType(0:MDIM),
integer(IN),optional :: jProcs,
integer(IN),optional :: kProcs,
integer(IN),optional :: refinementLevel,
real(IN), optional :: region_bndBox)
DESCRIPTION
This is the initialization routine for using Pfft. If needMap is true, routine creates a schedule of data transfers that would map AMR or UG grid to PFFT. This schedule is remembered internally by Pfft until the Grid_pfftFinalize routine is called. If needMap is false, it is assumed the data distribution is already compatible with Pfft requirements: That is along IAXIS, the entire row is within one processor. The routine also calls gr_pfftInitMetaData, which is responsible for calculating the trignometric tables, creating communicators necessary for distributed transposes in Pfft and allocates workspace
ARGUMENTS
ndim - dimensionality of the problem
needMap - should be true if the default shape is not compatible with
requirements of the input Pfft array. Only if
this argument is true, is the map determined.
globalLen - the globalsize of the domain
localArraySize - after mapping to pfft_grid, the local size for the domain
transformType - type of transform along each dimension
if none is specified we assume realtocomplex
in first dimension and complextocomplex in the rest
baseDatType - basic data type (rela or complex) along each dimension,
after the transform for that direction (if any),
the 0 component specifies data type before IAXIS transform.
jProcs,kProcs - if they are present, they decide the shape of the
processor grid for pfft. If they are not present,
a routine that can automatically determine the shape is
called.
refinementLevel - The block refinement level at which we will create the map.
region_bndBox - If the map is from a subset of the physical domain in AMR to
Pfft grid, this argument contains the bounding box of the region