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().

        Using a librsb  program via rsblib does not differ conceptually much librsb.

        Errors caught by librsb 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  then librsb 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