rdkit/Code/DataStructs/FPBReader.h

//
// Copyright (c) 2016 Greg Landrum
//
//  @@ All Rights Reserved @@
//  This file is part of the RDKit.
//  The contents are covered by the terms of the BSD license
//  which is included in the file license.txt, found at the root
//  of the RDKit source tree.
//
#ifndef RD_FPBREADER_H_DEC2015
#define RD_FPBREADER_H_DEC2015
/*! \file FPBReader.h

  \brief contains a simple class for reading and searching FPB files
*/

#include <iostream>
#include <fstream>
#include <sstream>
#include <string>
#include <RDGeneral/BadFileException.h>
#include <DataStructs/ExplicitBitVect.h>

#include <boost/cstdint.hpp>
#include <boost/shared_ptr.hpp>
#include <boost/shared_array.hpp>

namespace RDKit {
namespace detail {
struct FPBReader_impl;
}

//! class for reading and searching FPB files
/*!
  basic usage:
  \code
  FPBReader reader("foo.fpb");
  reader.init();
  boost::shared_ptr<ExplicitBitVect> ebv = reader.getFP(95);
  std::vector<std::pair<double, unsigned int> > nbrs =
      reader.getTanimotoNeighbors(*ebv.get(), 0.70);
  \endcode

*/
class FPBReader {
 public:
  FPBReader()
      : dp_istrm(NULL),
        dp_impl(NULL),
        df_owner(false),
        df_init(false),
        df_lazyRead(false){};
  //! ctor for reading from a named file
  /*!
  \param fname the name of the file to reads
  \param lazyRead if set to \c false all fingerprints from the file will be read
  into memory when \c init() is called.
  */
  FPBReader(const char *fname, bool lazyRead = false) {
    _initFromFilename(fname, lazyRead);
  };
  //! \overload
  FPBReader(const std::string &fname, bool lazyRead = false) {
    _initFromFilename(fname.c_str(), lazyRead);
  };
  //! ctor for reading from an open istream
  /*!
  \param inStream the stream to read from
  \param takeOwnership if set, we will take over ownership of the stream pointer
  \param lazyRead if set to \c false all fingerprints from the file will be read
  into memory when \c init() is called.

  Some additional notes:
    - if \c lazyRead is set, \c inStream must support the \c seekg() and \c
  tellg() operations.

  */
  FPBReader(std::istream *inStream, bool takeOwnership = true,
            bool lazyRead = false)
      : dp_istrm(inStream),
        df_owner(takeOwnership),
        df_init(false),
        df_lazyRead(lazyRead){};
  ~FPBReader() {
    destroy();
    if (df_owner) delete dp_istrm;
    dp_istrm = NULL;
    df_init = false;
  };

  //! Read the data from the file and initialize internal data structures
  /*!
  This must be called before most of the other methods of this clases.

  Some notes:
  \li if \c lazyRead is not set, all fingerprints will be read into memory. This
  can require substantial amounts of memory for large files.
  \li For large files, this can take a long time.
  \li If \c lazyRead and \c takeOwnership are both \c false it is safe to close
  and delete inStream after calling \c init()
  */
  void init();
  //! returns the requested fingerprint as an \c ExplicitBitVect
  boost::shared_ptr<ExplicitBitVect> getFP(unsigned int idx) const;
  //! returns the requested fingerprint as an array of bytes
  boost::shared_array<boost::uint8_t> getBytes(unsigned int idx) const;

  //! returns the id of the requested fingerprint
  std::string getId(unsigned int idx) const;
  //! returns the fingerprint and id of the requested fingerprint
  std::pair<boost::shared_ptr<ExplicitBitVect>, std::string> operator[](
      unsigned int idx) const {
    return std::make_pair(getFP(idx), getId(idx));
  };

  //! returns beginning and end indices of fingerprints having on-bit counts
  //! within the range (including end points)
  std::pair<unsigned int, unsigned int> getFPIdsInCountRange(
      unsigned int minCount, unsigned int maxCount);

  //! returns the number of fingerprints
  unsigned int length() const;
  //! returns the number of bits in our fingerprints
  unsigned int nBits() const;

  //! returns the tanimoto similarity between the specified fingerprint and the
  //! provided fingerprint
  double getTanimoto(unsigned int idx, const boost::uint8_t *bv) const;
  //! \overload
  double getTanimoto(unsigned int idx,
                     boost::shared_array<boost::uint8_t> bv) const {
    return getTanimoto(idx, bv.get());
  };
  //! \overload
  double getTanimoto(unsigned int idx, const ExplicitBitVect &ebv) const;

  //! returns tanimoto neighbors that are within a similarity threshold
  /*!
  The result vector of (similarity,index) pairs is sorted in order
  of decreasing similarity
  */
  std::vector<std::pair<double, unsigned int> > getTanimotoNeighbors(
      const boost::uint8_t *bv, double threshold = 0.7) const;
  //! \overload
  std::vector<std::pair<double, unsigned int> > getTanimotoNeighbors(
      boost::shared_array<boost::uint8_t> bv, double threshold = 0.7) const {
    return getTanimotoNeighbors(bv.get(), threshold);
  };
  //! \overload
  std::vector<std::pair<double, unsigned int> > getTanimotoNeighbors(
      const ExplicitBitVect &ebv, double threshold = 0.7) const;

  //! returns indices of all fingerprints that completely contain this one
  /*! (i.e. where all the bits set in the query are also set in the db
   molecule)
   */
  std::vector<unsigned int> getContainingNeighbors(
      const boost::uint8_t *bv) const;
  //! \overload
  std::vector<unsigned int> getContainingNeighbors(
      boost::shared_array<boost::uint8_t> bv) const {
    return getContainingNeighbors(bv.get());
  };
  //! \overload
  std::vector<unsigned int> getContainingNeighbors(
      const ExplicitBitVect &ebv) const;

 private:
  std::istream *dp_istrm;
  detail::FPBReader_impl *dp_impl;  // implementation details
  bool df_owner;
  bool df_init;
  bool df_lazyRead;

  // disable automatic copy constructors and assignment operators
  // for this class and its subclasses.  They will likely be
  // carrying around stream pointers and copying those is a recipe
  // for disaster.
  FPBReader(const FPBReader &);
  FPBReader &operator=(const FPBReader &);
  void destroy();
  void _initFromFilename(const char *fname, bool lazyRead) {
    std::istream *tmpStream = static_cast<std::istream *>(
        new std::ifstream(fname, std::ios_base::binary));
    if (!tmpStream || (!(*tmpStream)) || (tmpStream->bad())) {
      std::ostringstream errout;
      errout << "Bad input file " << fname;
      throw BadFileException(errout.str());
    }
    dp_istrm = tmpStream;
    df_owner = true;
    df_init = false;
    df_lazyRead = lazyRead;
  }
};
}
#endif