int main(int argc,char **argv)
{
PetscErrorCode ierr;
PetscInt degrees[1000],ndegrees,npoints,two;
PetscReal points[1000],weights[1000],interval[2];
PetscBool flg;
ierr = PetscInitialize(&argc,&argv,(char*)0,help);CHKERRQ(ierr);
ierr = PetscOptionsBegin(PETSC_COMM_WORLD,NULL,"Discretization tools test options",NULL);CHKERRQ(ierr);
{
ndegrees = 1000;
degrees[0] = 0;
degrees[1] = 1;
degrees[2] = 2;
ierr = PetscOptionsIntArray("-degrees","list of degrees to evaluate","",degrees,&ndegrees,&flg);CHKERRQ(ierr);
if (!flg) ndegrees = 3;
npoints = 1000;
points[0] = 0.0;
points[1] = -0.5;
points[2] = 1.0;
ierr = PetscOptionsRealArray("-points","list of points at which to evaluate","",points,&npoints,&flg);CHKERRQ(ierr);
if (!flg) npoints = 3;
two = 2;
interval[0] = -1.;
interval[1] = 1.;
ierr = PetscOptionsRealArray("-interval","interval on which to construct quadrature","",interval,&two,NULL);CHKERRQ(ierr);
}
ierr = PetscOptionsEnd();CHKERRQ(ierr);
ierr = CheckPoints("User-provided points",npoints,points,ndegrees,degrees);CHKERRQ(ierr);
ierr = PetscDTGaussQuadrature(npoints,interval[0],interval[1],points,weights);CHKERRQ(ierr);
ierr = PetscPrintf(PETSC_COMM_WORLD,"Quadrature weights\n");CHKERRQ(ierr);
ierr = PetscRealView(npoints,weights,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
{
PetscReal a = interval[0],b = interval[1],zeroth,first,second;
PetscInt i;
zeroth = b - a;
first = (b*b - a*a)/2;
second = (b*b*b - a*a*a)/3;
for (i=0; i<npoints; i++) {
zeroth -= weights[i];
first -= weights[i] * points[i];
second -= weights[i] * PetscSqr(points[i]);
}
if (PetscAbs(zeroth) < 1e-10) zeroth = 0.;
if (PetscAbs(first) < 1e-10) first = 0.;
if (PetscAbs(second) < 1e-10) second = 0.;
ierr = PetscPrintf(PETSC_COMM_WORLD,"Moment error: zeroth=%g, first=%g, second=%g\n",(double)(-zeroth),(double)(-first),(double)(-second));CHKERRQ(ierr);
}
ierr = CheckPoints("Gauss points",npoints,points,ndegrees,degrees);CHKERRQ(ierr);
ierr = PetscFinalize();
return 0;
}
static void AddEdgeToRing( OGRLinearRing * poRing, OGRLineString * poLine,
int bReverse )
{
/* -------------------------------------------------------------------- */
/* Establish order and range of traverse. */
/* -------------------------------------------------------------------- */
int iStart=0, iEnd=0, iStep=0;
int nVertToAdd = poLine->getNumPoints();
if( !bReverse )
{
iStart = 0;
iEnd = nVertToAdd - 1;
iStep = 1;
}
else
{
iStart = nVertToAdd - 1;
iEnd = 0;
iStep = -1;
}
/* -------------------------------------------------------------------- */
/* Should we skip a repeating vertex? */
/* -------------------------------------------------------------------- */
if( poRing->getNumPoints() > 0
&& CheckPoints( poRing, poRing->getNumPoints()-1,
poLine, iStart, NULL ) )
{
iStart += iStep;
}
/* -------------------------------------------------------------------- */
/* Append points to ring. */
/* -------------------------------------------------------------------- */
int iOutVertex = poRing->getNumPoints();
poRing->setNumPoints( iOutVertex + ABS(iEnd-iStart) + 1 );
for( int i = iStart; i != (iEnd+iStep); i += iStep )
{
poRing->setPoint( iOutVertex++,
poLine->getX(i), poLine->getY(i), poLine->getZ(i) );
}
}
OGRGeometryH OGRBuildPolygonFromEdges( OGRGeometryH hLines,
int bBestEffort,
int bAutoClose,
double dfTolerance,
OGRErr * peErr )
{
int bSuccess = TRUE;
OGRGeometryCollection *poLines = (OGRGeometryCollection *) hLines;
OGRPolygon *poPolygon = new OGRPolygon();
(void) bBestEffort;
/* -------------------------------------------------------------------- */
/* Setup array of line markers indicating if they have been */
/* added to a ring yet. */
/* -------------------------------------------------------------------- */
int nEdges = poLines->getNumGeometries();
int *panEdgeConsumed, nRemainingEdges = nEdges;
panEdgeConsumed = (int *) CPLCalloc(sizeof(int),nEdges);
/* ==================================================================== */
/* Loop generating rings. */
/* ==================================================================== */
while( nRemainingEdges > 0 )
{
int iEdge;
OGRLineString *poLine;
/* -------------------------------------------------------------------- */
/* Find the first unconsumed edge. */
/* -------------------------------------------------------------------- */
for( iEdge = 0; panEdgeConsumed[iEdge]; iEdge++ ) {}
poLine = (OGRLineString *) poLines->getGeometryRef(iEdge);
/* -------------------------------------------------------------------- */
/* Start a new ring, copying in the current line directly */
/* -------------------------------------------------------------------- */
OGRLinearRing *poRing = new OGRLinearRing();
AddEdgeToRing( poRing, poLine, FALSE );
panEdgeConsumed[iEdge] = TRUE;
nRemainingEdges--;
/* ==================================================================== */
/* Loop adding edges to this ring until we make a whole pass */
/* within finding anything to add. */
/* ==================================================================== */
int bWorkDone = TRUE;
double dfBestDist = dfTolerance;
while( !CheckPoints(poRing,0,poRing,poRing->getNumPoints()-1,NULL)
&& nRemainingEdges > 0
&& bWorkDone )
{
int iBestEdge = -1, bReverse = FALSE;
bWorkDone = FALSE;
dfBestDist = dfTolerance;
// We consider linking the end to the beginning. If this is
// closer than any other option we will just close the loop.
//CheckPoints(poRing,0,poRing,poRing->getNumPoints()-1,&dfBestDist);
// Find unused edge with end point closest to our loose end.
for( iEdge = 0; iEdge < nEdges; iEdge++ )
{
if( panEdgeConsumed[iEdge] )
continue;
poLine = (OGRLineString *) poLines->getGeometryRef(iEdge);
if( CheckPoints(poLine,0,poRing,poRing->getNumPoints()-1,
&dfBestDist) )
{
iBestEdge = iEdge;
bReverse = FALSE;
}
if( CheckPoints(poLine,poLine->getNumPoints()-1,
poRing,poRing->getNumPoints()-1,
&dfBestDist) )
{
iBestEdge = iEdge;
bReverse = TRUE;
}
}
// We found one within tolerance - add it.
if( iBestEdge != -1 )
{
poLine = (OGRLineString *)
poLines->getGeometryRef(iBestEdge);
AddEdgeToRing( poRing, poLine, bReverse );
panEdgeConsumed[iBestEdge] = TRUE;
nRemainingEdges--;
bWorkDone = TRUE;
}
}
/* -------------------------------------------------------------------- */
/* Did we fail to complete the ring? */
/* -------------------------------------------------------------------- */
dfBestDist = dfTolerance;
if( !CheckPoints(poRing,0,poRing,poRing->getNumPoints()-1,
&dfBestDist) )
{
CPLDebug( "OGR",
"Failed to close ring %d.\n"
"End Points are: (%.8f,%.7f) and (%.7f,%.7f)\n",
poPolygon->getNumInteriorRings()+1,
poRing->getX(0), poRing->getY(0),
poRing->getX(poRing->getNumPoints()-1),
poRing->getY(poRing->getNumPoints()-1) );
bSuccess = FALSE;
}
/* -------------------------------------------------------------------- */
/* Do we need to auto-close this ring? */
/* -------------------------------------------------------------------- */
if( bAutoClose
&& !CheckPoints(poRing,0,poRing,poRing->getNumPoints()-1,NULL) )
{
poRing->addPoint( poRing->getX(0),
poRing->getY(0),
poRing->getZ(0));
}
poPolygon->addRingDirectly( poRing );
} /* next ring */
/* -------------------------------------------------------------------- */
/* Cleanup. */
/* -------------------------------------------------------------------- */
CPLFree( panEdgeConsumed );
// Eventually we should at least identify the external ring properly,
// perhaps even ordering the direction of rings, though this isn't
// required by the OGC geometry model.
if( peErr != NULL )
{
if( bSuccess )
*peErr = OGRERR_NONE;
else
*peErr = OGRERR_FAILURE;
}
return (OGRGeometryH) poPolygon;
}
