NAME

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

DESCRIPTION

SYNOPSIS

   Data Structures
       class RsbLib
           Class initializing/finalizing librsb state.
       class RsbMatrix< NT >
           Represent a sparse matrix in RSB format by means of librsb.

   Macros
       #define RSBP_DEPRECATED
           Internal attribute specifier for deprecated member functions.
       #define RSBP_NODISCARD
           Internal attribute.
       #define RSBP_WANT_REV   0
           If this is defined to 1 before including <rsb.hpp>, rsb_err_t is the default return
           type. Otherwise the default is void.
       #define RSBP_RVT   template <typename Err_t=void>
           No return type.
       #define RSBP_MSLVRV   10201
           Minimal supported librsb version (value of RSB_LIBRSB_VER, defined via rsb.h)

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().
                                 sblib does not differ conceptually much rsb.
        Using a rsb  program via

        Errors caught by rsb shall not go unnoticed 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 rsb is 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
           Michele Martone

Macro Definition Documentation

   #define RSBP_DEPRECATED
       Internal attribute specifier for deprecated member functions. Header-only (rsb.hpp)
       wrapper classes for librsb (http://librsb.sf.net).

   #define RSBP_MSLVRV   10201
       Minimal supported librsb version (value of RSB_LIBRSB_VER, defined via rsb.h)

   #define RSBP_NODISCARD
       Internal attribute.

   #define RSBP_RVT   template <typename Err_t=void>
       No return type.

   #define RSBP_WANT_REV   0
       If this is defined to 1 before including <rsb.hpp>, rsb_err_t is the default return type.
       Otherwise the default is void.

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