RipsPersistenceDiagram.cpp

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#include <RipsPersistenceDiagram.h>
 
static bool isPrime(int n) {
  if(n <= 1)
    return false;
  for(int d = 2; d * d <= n; ++d) {
    if(n % d == 0)
      return false;
  }
  return true;
}
 
ttk::RipsPersistenceDiagram::RipsPersistenceDiagram() {
  // inherited from Debug: prefix will be printed at the beginning of every msg
  this->setDebugMsgPrefix("RipsPersistenceDiagram");
}
 
int ttk::RipsPersistenceDiagram::execute(
  const rpd::PointCloud &points, rpd::MultidimensionalDiagram &ph) const {
 
  bool forceRipser = false;
 
  if(BackEnd == BACKEND::GEOMETRY) {
#ifdef TTK_ENABLE_CGAL
    if(points[0].size() == 2) {
      rpd::FastRipsPersistenceDiagram2 FRPD(points);
      FRPD.setDebugLevel(debugLevel_);
      FRPD.computeRips0And1Persistence(ph, false, false);
    } else {
      printWrn("Geometric method only implemented for dim 2.");
      printWrn("Ripser will be used instead.");
      forceRipser = true;
    }
#else
    printWrn("TTK was not compiled with CGAL.");
    printWrn("Ripser will be used instead.");
    forceRipser = true;
#endif
  }
 
  if(BackEnd == BACKEND::RIPSER || forceRipser) {
    if(isPrime(FieldOfCoefficients))
      ripser::ripser(points, ph, SimplexMaximumDiameter,
                     HomologyMaximumDimension, InputIsDistanceMatrix, false,
                     true, FieldOfCoefficients);
    else {
      printErr("The chosen p=" + std::to_string(FieldOfCoefficients)
               + " is not prime");
      return 1;
    }
  }
 
  return 0;
}