CPPLapack Code

//=============================================================================
/*! _dgematrix+dgbmatrix operator */
inline _dgematrix operator+(const _dgematrix& matA, const dgbmatrix& matB)
{CPPL_VERBOSE_REPORT;
#ifdef  CPPL_DEBUG
  if(matA.n!=matB.n || matA.m!=matB.m){
    ERROR_REPORT;
    std::cerr << "These two matrises can not make a summation." << std::endl
              << "Your input was (" << matA.m << "x" << matA.n << ") + (" << matB.m << "x" << matB.n << ")." << std::endl;
    exit(1);
  }
#endif//CPPL_DEBUG
  
  for(long i=0; i<matB.m; i++){
    const long jmax =std::min(matB.n,i+matB.ku+1);
    for(long j=std::max(0l,i-matB.kl); j<jmax; j++){
      matA(i,j) += matB(i,j);
    }
  }
  
  return matA;
}

//=============================================================================
/*! _dgematrix-dgbmatrix operator */
inline _dgematrix operator-(const _dgematrix& matA, const dgbmatrix& matB)
{CPPL_VERBOSE_REPORT;
#ifdef  CPPL_DEBUG
  if(matA.n!=matB.n || matA.m!=matB.m){
    ERROR_REPORT;
    std::cerr << "These two matrises can not make a summation." << std::endl
              << "Your input was (" << matA.m << "x" << matA.n << ") + (" << matB.m << "x" << matB.n << ")." << std::endl;
    exit(1);
  }
#endif//CPPL_DEBUG
  
  for(long i=0; i<matB.m; i++){
    const long jmax =std::min(matB.n,i+matB.ku+1);
    for(long j=std::max(0l,i-matB.kl); j<jmax; j++){
      matA(i,j) -= matB(i,j);
    }
  }
  
  return matA;
}

//=============================================================================
/*! _dgematrix*dgbmatrix operator */
inline _dgematrix operator*(const _dgematrix& matA, const dgbmatrix& matB)
{CPPL_VERBOSE_REPORT;
#ifdef  CPPL_DEBUG
  if(matA.n!=matB.m){
    ERROR_REPORT;
    std::cerr << "These two matrises can not make a product." << std::endl
              << "Your input was (" << matA.m << "x" << matA.n << ") * (" << matB.m << "x" << matB.n << ")." << std::endl;
    exit(1);
  }
#endif//CPPL_DEBUG
  
  dgematrix newmat( matA.m, matB.n );
  newmat.zero();
  
  for(long i=0; i<newmat.m; i++){
    for(long j=0; j<newmat.n; j++){
      const long kmax =std::min(matB.m,j+matB.kl+1);
      for(long k=std::max(0l,j-matB.ku); k<kmax; k++){
        newmat(i,j) += matA(i,k)*matB(k,j);
      }
    }
  }
  
  matA.destroy();
  return _(newmat);
}