rdkit/Docs/Book/C++Examples/example2.cpp

//
// Reading molecules - example2.cpp

#include <fstream>
#include <iostream>
#include <string>
#include <GraphMol/GraphMol.h>
#include <GraphMol/FileParsers/MolSupplier.h>

#include <boost/iostreams/device/file.hpp>
#include <boost/iostreams/filtering_stream.hpp>
#include <boost/iostreams/filter/gzip.hpp>
#include <boost/iostreams/stream.hpp>

int main(int argc, char **argv) {
  std::string file_root = getenv("RDBASE");
  file_root += "/Docs/Book";

  std::unique_ptr<RDKit::ROMol> mol;
  std::string sdf_file = file_root + "/data/5ht3ligs.sdf";
  bool takeOwnership = true;
  RDKit::SDMolSupplier mol_supplier(sdf_file, takeOwnership);
  while (!mol_supplier.atEnd()) {
    mol.reset(mol_supplier.next());
    std::cout << mol->getProp<std::string>("_Name") << " has "
              << mol->getNumAtoms() << " atoms." << std::endl;
  }

  for (int i = int(mol_supplier.length()) - 1; i >= 0; --i) {
    std::unique_ptr<RDKit::ROMol> mol(mol_supplier[i]);
    if (mol) {
      std::cout << mol->getProp<std::string>("_Name") << " has "
                << mol->getNumAtoms() << " atoms." << std::endl;
    }
  }

  boost::iostreams::filtering_istream ins;
  ins.push(boost::iostreams::gzip_decompressor());
  std::string comp_sdf_file = file_root + "/data/actives_5ht3.sdf.gz";
  ins.push(boost::iostreams::file_source(comp_sdf_file));
  // takeOwnership must be false for this, as we don't want the SDWriter trying
  // to delete the boost::iostream
  takeOwnership = false;
  RDKit::ForwardSDMolSupplier forward_supplier(&ins, takeOwnership);
  while (!forward_supplier.atEnd()) {
    mol.reset(forward_supplier.next());
    if (mol) {
      std::cout << mol->getProp<std::string>("_Name") << " has "
                << mol->getNumAtoms() << " atoms." << std::endl;
    }
  }

  // This is not allowed, and will give a compiler error:
  // mol.reset(forward_supplier[1]);
}