Group Information

Fundamental information about grid functions (e.g. local grid size and location, number of ghostzones) is passed through the argument list of scheduled routines (see Section B7.2.3). To obtain similar information from non-scheduled routines, or for general grid variables, a set of functions are provided, the last two letters of which specify whether the information is requested using a group name (GN) or index (GI), or a variable name (VN) or index (VI).

CCTK_Grouplsh[GN|GI|VN|VI]

An array of integers with the local grid size on this processor.

CCTK_Groupgsh[GN|GI|VN|VI]

An array of integers with the global grid size.

CCTK_Groupbbox[GN|GI|VN|VI]

An array of integers which indicate whether the boundaries are internal boundaries (e.g. between processors), or physical boundaries. A value of 1 indicates a physical (outer) boundary at the edge of the computational grid, and 0 indicates an internal boundary.

CCTK_Groupnghostzones[GN|GI|VN|VI]

An array of integers with the number of ghostzones used in each direction.

CCTK_Grouplbnd[GN|GI|VN|VI]

An array of integers containing the lowest index (in each direction) of the local grid, as seen on the global grid. Note that these indices start from zero, so you need to add one when using them in Fortran thorns.

CCTK_Groupubnd[GN|GI|VN|VI]

An array of integers containing the largest index (in each direction) of the local grid, as seen on the global grid. Note that these indices start from zero, so you need to add one when using them in Fortran thorns.