(3M) Calculator User Manual

A brief on-line help is provided with all the programs . To get this help, use the
“-h” option after the pro gram name. The case of option letters is not significant,
except when both the lower and upper cases of a letter have different meanings.
When passing parameter s to the programs, only the order of file names is significant;
options can be put anywhere in the command line, in any order. Examples of use
of the different programs of the Scotch project are provided in section 9.
Error messages a re standardized, but may not be fully explanatory. However,
most of the errors you may run into should be related to file formats, and located
in “...Load” routines. In this case, co mpare your data formats with the definitions
given in sec tion 5, and use the gtst and mtst programs to check the consistency of
source graphs and meshes.
6.2 Using compressed files
Starting from version 5.0.6, Scotch allows users to provide and retrieve data in
compressed form. Since this feature requires that the compres sion and decompres-
sion tasks run in the same time as data is read or written, it can only be done
on systems which support multi-threading (Posix threads) or multi-processing (by
means of fork system calls).
To determine if a stream has to be handled in compressed form, Scotch checks
its ex tension. If it is “.gz” (gzip format), “.bz2” (bzip2 format) or “.lzma” (lzma
format), the stream is assumed to be compr e ssed acco rding to the co rresponding
format. A filter task will then be used to process it accordingly if the format is
implemented in Scotch and enabled on your system.
To date, data can be read and written in bzip2 and gzip formats, and can
also be re ad in the lzma format. Since the compression ratio of lzma on Scotch
graphs is 30% better than the one of gzip a nd bzip2 (which are almost equiva le nt
in this case), the lzma format is a very good choice for handling very large graphs.
To see how to enable compressed data handling in Scotch, please refer to Section 8.
When the compr essed format allows it, several files can be provided on
the same str e am, and be uncompress e d on the fly. For instance, the
command “cat brol.grf.gz brol.xyz.gz | gout -.gz -.gz -Mn - brol.iv”
concatenates the topolo gy and geometry data of some graph brol and feed them
as a single compressed stream to the standard input of progra m gout, hence the
”-.gz” to indicate a compressed standard stream.
6.3 Description
6.3.1 acpl
Synopsis
acpl [input
target file [output target file]] options
Description
The program acpl is the decompo sition-defined architecture file compiler. It
processes architecture files of type “deco 0” built by hand or by the amk
*
programs, to cr e ate a “deco 1” compiled architecture file of about four times
the size of the original one; see section 5.4.1, page 23, for a detailed description
of decomposition-defined target architecture file formats.
The mapper can read both original and compiled architecture file for mats.
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