text: /*
   *  Copyright 2016 NVIDIA Corporation
   *
   *  Licensed under the Apache License, Version 2.0 (the "License");
   *  you may not use this file except in compliance with the License.
   *  You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   *  Unless required by applicable law or agreed to in writing, software
   *  distributed under the License is distributed on an "AS IS" BASIS,
   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   *  See the License for the specific language governing permissions and
   *  limitations under the License.
   */
  #pragma once
  #include "vector.h"
  #include "matrix.h"
  
  void matvec(const matrix& A, const vector& x, const vector &y) {
  
    unsigned int num_rows=A.num_rows;
    unsigned int *row_offsets=A.row_offsets;
    unsigned int *cols=A.cols;
    double *Acoefs=A.coefs;
    double *xcoefs=x.coefs;
    double *ycoefs=y.coefs;
  
    for(int i=0;i<num_rows;i++) {
      double sum=0;
      int row_start=row_offsets[i];
      int row_end=row_offsets[i+1];
      for(int j=row_start;j<row_end;j++) {
        unsigned int Acol=cols[j];
        double Acoef=Acoefs[j];
        double xcoef=xcoefs[Acol];
        sum+=Acoef*xcoef;
      }
      ycoefs[i]=sum;
    }
  }
  