CactusBase Overview
- Boundary
- This thorn defines a generic interface for boundary conditions, which allows, among other things, symmetry boundary conditions associated with the grid to be applied without other thorns having knowledge of them.
- CartGrid3D
- This thorn sets up a Cartesian grid, for a given domain. It also provides a method for registering symmetries of Grid Functions across the grid axes, and a call for applying symmetry boundary conditions. CartGrid3d also registers a coordinate system spher3d, under the old API, but this is deprecated. Spherical coordinate systems will be provided by another thorn in the future.
- CoordBase
- Provides generic handling of coordinates for grid arrays.
- IOASCII
- This thorn does 1D, 2D, and 3D output of 3D variables in ASCII format. 1D output slices through the edge (in octant mode) or center (in all origin-centered modes) of the grid in the x,y, and z directions. If the grid is cubed it will also slice in the diagonal direction. Ouput files can be processed with either gnuplot or xgraph. 2D output is done for the xy, xz, and yz plane. Ouput files can be processed with the splot command in gnuplot. 3D output is simply done for the full 3D grid variables. Ouput files can be processed with the splot command in gnuplot.
- IOBasic
- This thorn provides two I/O methods "Info" and "Scalar" which output grid
variables as scalars as a function on time.
Grid scalars:
- Output the value of the scalar straight forwardly
- Output the reduction value of the grid function versus time. For this you also need to activate a thorn which implements reduction operators (eg. PUGHReduce which provides the standard reductions "minimum", "maximum", "sum", "norm1", "norm2", and "norm_inf").
- IOUtil
- This thorn is the flesh for IO - it always needs to be activated if you want to do some IO in Cactus. The thorn just provides basic IO parameters. These are used in other IO thorns which do the real work. It also provides a method for registration of recovery routines.
- InitBase
- Thorn InitBase specifis how initial data are to be set up. It does not set up any initial data by itself, nor does it contain any routines which are to be called. It is merely a convenient repository remembering how initial data are to be set up, so that other thorns can check their actions against this thorn.
- LocalInterp
- This thorn does processor-local interpolation of N-dimensional data arrays. In general there may be many input arrays (all defined on the same uniform Cartesian grid) all being interpolated to the same set of interpolation points.
- LocalReduce
- This thorn does processor-local reduction of N-dimensional data arrays.
- SymBase
- Provide generic handling of symmetries for grids and grid arrays.
- Time
- Thorn Time sets the timestep for the simulation by either - setting the timestep directly from a parameter value - using a Courant-type condition to set the timestep based on the grid-spacing used. The Courant condition can be applied either once at the start of the simulation, or the timestep can be calculated dynamically before each timestep.
Created by
swhite
Last modified 2008-04-14 08:41 AM
Last modified 2008-04-14 08:41 AM
Cactus runs on 131,072 cores on Blue Gene/P at ANL
