(3M) Calculator User Manual

7.11 Geometry handling routines
Since the Scotch project is based on algorithms that rely on topology data only,
geometry data do not play an important role in the libScotch library. They are
only relevant to programs that display graphs, such as the gout program. However,
since all routines that are used by the programs of the Scotch distributions have
an interface in the libScotch library, ther e exist geometry handling routines in it,
which manipulate SCOTCH Geom structures.
Apart from the routines that create, destroy or acce ss SCOTCH Geom structures,
all of the routines in this section are input/output routines, which read or write
both SCOTCH
Graph and SCOTCH Geom structures. We have chosen to define the
interface of the geometry-handling routines such that they also handle graph or
mesh topology because some external file formats mix these data, and that we
wanted our routines to be able to read their data on the fly from streams that can
only be read once, such as communication pipes. Having both aspects taken into
account in a single call makes the writing of file c onversion tools, such as gcv and
mcv, very easy. When the file format from which to read or into which to write
mixes both sorts of data, the geometry file pointer can be set to NULL, as it will not
be used.
7.11.1 SCOTCH
geomInit
Synopsis
int SCOTCH
geomInit (SCOTCH Geom * geomptr)
scotchfgeominit (doubleprecision (*) geomdat,
integer ierr)
Description
The SCOTCH geomInit function initializes a SCOTCH Geom structure so a s to
make it suitable for future operations. It should be the first function to be
called upon a SCOTCH
Geom structure. When the geometrical data is no longer
of use, call function SCOTCH geomExit to free its internal structures.
Return val ues
SCOTCH
geomInit r eturns 0 if the geometrical structure has been successfully
initialized, and 1 else.
7.11.2 SCOTCH
geomExit
Synopsis
void SCOTCH
geomExit (SCOTCH Geom * geomptr)
scotchfgeomexit (doubleprecision (*) geomdat)
Description
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