Using IWAVE

Scripted Examples

To build the intermediate data and figures for the examples described here,,

• install IWAVE, either within Madagascar or standalone. I will use $TOP to denote the path to the top-level IWAVE directory for the standalone version, or to the top-level Madagascar build directory $RSFSRC.
• for the standalone version of IWAVE, the examples build with the assistance of SU, which must also be installed. The choice of word order in IWAVE and SU must be compatible: either the XDR option must be set in both, or in neither. Default for both IWAVE and SU is native binary word order. To set the XDR option for SU, follow instructions in Makefile.config; for IWAVE, configure compilation with the flag -DSUXDR, as described in Appendix B and (Terentyev et al., 2012).
• the Madagascar version builds with entirely with Madagascar commands, so no external package need be supplied.
• build data and figures: in the standalone version of IWAVE,
  • cd $TOP/demo/data
  • scons
  , or, in the Madagascar version,
  • cd $TOP/book/trip/iwave/data
  • scons
  • scons lock -f madfig.sc
  (the last step is necessary only if you wish to build a copy of this paper from source - it archives the newly created figures and makes them available to the paper build, as described in the next bullet)
• to (re)build this paper, build the figures first. Then in the standalone version,
  • cd $TOP/papers
  • scons
  or, in the Madagascar version,
  • cd $TOP/book/iwave
  • scons

Note that the finest (2.5 m) grid consists of roughly 10 million gridpoints. Consequently the modeling runs collectively take a considerable time, from a minutes to a substantial fraction of an hour depending on platform, on a single thred. This example is computationally large enough that parallelism via domain decomposition is worthwhile. IWAVE is designed from the ground up to support parallel computation; a companion report will demonstrate parallel use of IWAVE.

Inspection of the SConstruct file in data will show that the modeling tool used is $TOP/asg/main/asg.x, the IWAVE acoustic modeling command (in Madagascar Flows, this command is referenced simply as asg, which is an alias for $RSFROOT/bin/sfasg, where $RSFROOT is an alias for the Madagascar install directory). Input data is supplied by a parameter list, stored in a file. The model-building tool standardmodel builds the velocity and density model files, and works the same way - many of the parameter files in the data directory are input for this tool.

Both the IWAVE acoustic modeling command and standardmodel self-doc in the style of SU or Madagascar. For modeling command, the self-doc is deprecated in favor of the web documentation mentioned above.

Using IWAVE