NAME
Grid_getBlkData
SYNOPSIS
Grid_getBlkData(integer(IN) :: blockID,
integer(IN) :: gridDataStruct,
integer(IN) :: structIndex,
integer(IN) :: beginCount,
integer(IN) :: startingPos(MDIM),
real(OUT) :: datablock(dataSize(1),dataSize(2), dataSize(3)),
integer(IN) :: dataSize(3))
DESCRIPTION
This routine allows the user to get an entire block or any contiguous part of a block of data depending on the arguments passed. The data could be either a single variable in one of the grid data structures such as cell centered/face centered/scratch, or it could be quantities derived from the size of the cell, such as cell volume/ face area for all the cells in the specified portion of the block The user is also allowed to specify if index counting should begin at the exterior edge of the block (that is including guardcells), or the interior edge of the block. For 3 dimensional problems, a 3d block is returned. For 2 dimensional problems, a 2d block/plane is returned. For 1 dimensional problems, a 1d block/row is returned.
ARGUMENTS
blockID : the local blockid
gridDataStruct : integer value specifying the type of data desired.
Valid options are either one of the Grid data structures,
or one of the derived quantities such as the cell volume
or the cell area.
The options are defined in constants.h and they are :
CENTER cell centered variables
FACEX face centered variable on faces along IAXIS
FACEY face centered variable on faces along JAXIS
FACEZ face centered variable on faces along IAXIS
WORK single, cell centered variable, valid only
for paramesh
SCRATCH scratch space that can fit cell and face centered variables
SCRATCH_CTR scratch space for cell centered variables
SCRATCH_FACEX scratch space facex variables
SCRATCH_FACEY scratch space facey variables
SCRATCH_FACEZ scratch space facez variables
CELL_VOLUME volumes of specified cells
CELL_FACEAREA face area for the specified cells on
specified face
structIndex : integer value that provides index into the specified data
structure. When gridDataStruct is one of the grid data structures
structIndex translates to a specific variable in that
data structure, for example: DENS_VAR or PRES_VAR (define in
Flash.h) if gridDataStruct = CENTER.
For gridDataStruct=CELL_VOLUME it has no meaning
For gridDataStruct = CELL_FACEAREA, it can take one of
(ILO_FACE,IHI_FACE,JLO_FACE,JHI_FACE,KLO_FACE,KHI_FACE)
defined in constants.h
beginCount : tells the routine where to start index counting. beginCount can
be set to INTERIOR or EXTERIOR. If INTERIOR is specified
guardcell indices are not included and index 1 is the first interior cell.
If EXTERIOR is specified
the first index, 1, is the left most guardcell. See example
below for more explanation. (For most of the FLASH architecture code,
we use EXTERIOR. Some physics routines, however, find it helpful
only to work on the internal parts of the blocks (without
guardcells) and wish to keep loop indicies
going from 1 to NXB without having to worry about finding
the correct offset for the number of guardcells.)
(INTERIOR and EXTERIOR are defined in constants.h)
startingPos(MDIM):
specifies the starting position of the block being fetched
startingPos(1) = i
startingPos(2) = j
startingPos(3) = k
If a problem is 2 dimensions startingPos(3) is irrelevant and
ignored. For 1d problems startingPos(2) and startingPos(3)
are ignored.
datablock : a real 3 dimensional array containing the data returned
The dimensions for datablock are
datablock(irange, jrange, krange)
Various compilers require the dimensions of
datablock to be specified explicitly. They are defined by
the next argument "dataSize".
dataSize : an integer array specifying the dimensions for datablock
dataSize(1) holds the number of cells returned in the i direction
dataSize(2) holds the number of cells returned in the j direction
if 1 dim problem set dataSize(2) = 1
dataSize(3) holds the number of cells returned in the k direction
if 1 or 2 dim problem set dataSize(3) = 1
EXAMPLE
EXAMPLE 1:
Here is a 3d block example getting the entire block of cell centered
data, including guardcells,
for each block on a local processor. beginCount is set to EXTERIOR
meaning that the first cell of the block including guardcells is
index = 1. If in this example, NGUARD = 4 then position 5 is the
first interior cell in a dimension.
(Can't really draw 3d for this example, but this
picture is meant to help show where
counting begins when "beginCount" is set to EXTERIOR)
j
16 - - - - - - - -
15 - - - - - - - -
14 - - - - - - - -
13 - - - - - - - -
12 - - - -|-|-|-|-|-|-|-|-|- - - -
11 - - - -|-|-|-|-|-|-|-|-|- - - -
10 - - - -|-|-|-|-|-|-|-|-|- - - -
9 - - - -|-|-|-|-|-|-|-|-|- - - -
8 - - - -|-|-|-|-|-|-|-|-|- - - -
7 - - - -|-|-|-|-|-|-|-|-|- - - -
6 - - - -|-|-|-|-|-|-|-|-|- - - -
5 - - - -|-|-|-|-|-|-|-|-|- - - -
4 - - - - - - - -
3 - - - - - - - -
2 - - - - - - - -
1 - - - - - - - -
i 1 2 3 4 5 6 7 8 9 10111213141516
#include "Flash.h"
#include "constants.h"
...
integer :: startingPos(MDIM)
integer :: dataSize(3)
integer :: blockID
real :: dataBlock(:,:,:)
startingPos(1) = 1 !getting the entire extent of dim
startingPos(2) = 1 !getting the entire extent of dim
startingPos(3) = 1 !getting the entire extent of dim
dataSize(1) = blkLimitsGC(IAXIS) !This is equivalent to NXB + 2*NGUARD
!in FIXEDBLOCKSIZE mode
dataSize(2) = blkLimitsGC(JAXIS) !This is equivalent to NYB + 2*NGUARD
!in FIXEDBLOCKSIZE mode
dataSize(3) = blkLimitsGC(KAXIS) !This is equivalent to NZB + 2*NGUARD
!in FIXEDBLOCKSIZE mode
allocate(datablock(dataSize(1), dataSize(2), dataSize(3)))
do blockID = 1, localNumBlocks
call Grid_getBlkData(blockID, CENTER, DENS_VAR, EXTERIOR, &
startingPos, dataBlock, dataSize)
end do
EXAMPLE 2:
In this 2d block example we will get cell volume of only a portion
of the interior part of a block for each block on the local processor.
beginCount is set to INTERIOR, meaning that all the startPos indices
will start where index 1 is the first interior cell of the block.
In this example we will get only the last 2 columns of interior cells.
i start position = 7, j start position = 1. (Because this is only a 2d
problem Grid_getPlaneData could also be used to get these cells.)
(Hard to draw, but this is the idea, stars (*) are the cells to return.
Notice where index counting starts when beginCount is set to INTERIOR)
- - - - - - - -
- - - - - - - -
- - - - - - - -
j - - - - - - - -
8 ----|-|-|-|-|-|-|*|*|----
7 ----|-|-|-|-|-|-|*|*|----
6 ----|-|-|-|-|-|-|*|*|----
5 ----|-|-|-|-|-|-|*|*|----
4 ----|-|-|-|-|-|-|*|*|----
3 ----|-|-|-|-|-|-|*|*|----
2 ----|-|-|-|-|-|-|*|*|----
1 ----|-|-|-|-|-|-|*|*|----
- - - - - - - -
- - - - - - - -
- - - - - - - -
- - - - - - - -
i 1-2-3-4 5-6-7-8
#include "Flash.h"
#include "constants.h"
...
integer :: startingPos(MDIM)
integer :: dataSize(3)
integer :: blockID
real :: dataBlock(:,:,:)
startingPos(1) = 7
startingPos(2) = 1
startingPos(3) = 1 !value ignored since only 2d
dataSize(1) = 2 !just getting 2 cells in the i dir
dataSize(2) = 8 !just getting 8 cells in the j dir
dataSize(3) = 1 !needs to be set to 1, since only 2d problem
allocate(datablock(dataSize(1), dataSize(2), dataSize(3)))
do blockID = 1, localNumBlocks
call Grid_getBlkData(blockID, CELL_VOLUME, 0, INTERIOR, &
startingPos, dataBlock, dataSize)
end do