NAME¶

librsb - rsblib/rsb.hpp - Classes RsbLib and RsbMatrix provide native C++ access to librsb.

DESCRIPTION¶

SYNOPSIS¶

Detailed Description¶

Classes RsbLib and RsbMatrix provide native C++ access to librsb.

Most of the librsb functionality is available via C++ classes RsbLib and RsbMatrix.
These classes are defined in header file <rsb.hpp>, which wraps functionality of librsb's C interface <rsb.h>.
The RsbMatrix class can manipulate sparse matrices of several numerical types (same ones as librsb: matrix_supported_numerical_types_section).
Before using RsbMatrix, the library must be initialized by having a RsbLib object.
To avoid problems when including this header, don't define preprocessor macros prefixed with RSB_ or RSBP_.

For a quick start, check out examples/example.cpp or other examples in its directory.

/*
Copyright (C) 2020-2022 Michele Martone
This file is part of librsb.
librsb is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published
by the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
librsb is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
License for more details.
You should have received a copy of the GNU Lesser General Public
License along with librsb; see the file COPYING.
If not, see <http://www.gnu.org/licenses/>.
*/
/*!


 \ingroup rsb::examples


  @author Michele Martone


 @brief C++ example based on <rsb.hpp> using RsbMatrix.spmm().


 Using a a sblib does not differ conceptually much 


 Errors caught by ced and trigger an exception instead.


 Memory management of matrices and the library state itself follow the usual C++ RAII rules:


 the \c mtx object is freed first via RsbMatrix's destructor;


 then s finalized via RsbLib()'s destructor .


 \include example.cpp


 */
#include <rsb.hpp>
using namespace rsb;
#ifdef RSB_NUMERICAL_TYPE_DOUBLE
#if RSBP_WANT_CPP20
#include <vector>
#include <array>
/* If your compiler is C++20 compatible, the std::span-based interface is available like: */
auto main() -> int {


  RsbLib rsblib;


  const rsb_nnz_idx_t nnzA { 7 };


  const rsb_coo_idx_t nrA { 6 }, ncA { 6 }, nrhs { 2 };


  const rsb_coo_idx_t IA [nnzA] {0,1,2,3,4,5,1};


  std::array<rsb_coo_idx_t,7> JA {0,1,2,3,4,5,0};


  std::vector<double> VA {1,1,1,1,1,1,2}, X(nrhs*ncA,1);


  std::vector<double> Y(nrhs*nrA,0);


  const double alpha {2}, beta {1};


  rsb_int_t tn {0};


  rsb_real_t sf {0}; // speedup factor (tune_spmm output)


  const rsb_flags_t order {RSB_FLAG_WANT_COLUMN_MAJOR_ORDER};


  // IA,JA,VA are respectively from a C array, std::vector, std::array;


  // here using the C++20's std::span interface:


  RsbMatrix<double> mtx(IA,JA,VA);


  mtx.file_save(); // rsb_file_mtx_save


  mtx.tune_spmm(sf,RSB_TRANSPOSITION_N,alpha,nrhs,order,X,beta,Y); // rsb_tune_spmm


  mtx.spmm(RSB_TRANSPOSITION_N,alpha,nrhs,order,X,beta,Y); // rsb_spmv
}
#else
#include <vector>
/* The pointer-based interface is available as well: */
auto main() -> int {


  RsbLib rsblib;


  const rsb_nnz_idx_t nnzA { 7 };


  const rsb_coo_idx_t nrA { 6 }, ncA { 6 }, nrhs { 1 };


  const std::vector<rsb_coo_idx_t> IA {0,1,2,3,4,5,1}, JA {0,1,2,3,4,5,0};


  const std::vector<double> VA {1,1,1,1,1,1,2}, X(ncA,1);


  std::vector<double> Y(nrA,0);


  const double alpha {2}, beta {1};


  rsb_int_t tn {0};


  rsb_real_t sf {0}; // speedup factor (tune_spmm output)


  RsbMatrix<double> mtx(IA.data(),JA.data(),VA.data(),nnzA);


  mtx.file_save(nullptr); // rsb_file_mtx_save


  mtx.tune_spmm(&sf,&tn,0,0.0,RSB_TRANSPOSITION_N,alpha,nrhs,RSB_FLAG_WANT_COLUMN_MAJOR_ORDER,X.data(),ncA,beta,Y.data(),nrA); // rsb_tune_spmm


  mtx.spmv(RSB_TRANSPOSITION_N, alpha, X.data(), beta, Y.data()); // rsb_spmv
}
#endif
#else
auto main() { }
#endif

Author

Macro Definition Documentation¶

Author¶

librsb was written by Michele Martone; this documentation has been generated by Doxygen.

SEE ALSO¶

rsb-examples rsb-spblas.h rsb.h rsb.hpp