CPPLapack Code

//=============================================================================
//! Samll Real Double-precision General Dence Matrix Class
template<long M, long N> class dgematrix_small
{
public:
  //////// data ////////
  static const long m =M;
  static const long n =N;
  double array[M*N];
  
  //////// constructor ////////
  dgematrix_small(){;}
  dgematrix_small(const double& x){
    for(long k=0; k<M*N; k++){ array[k]=x; }
  }
  ~dgematrix_small(){;}
  
  //////// function ////////
  double& operator()(const long& i, const long& j);
  double  operator()(const long& i, const long& j)const;
  
  dgematrix_small<M,N>& zero(){
    for(long k=0; k<M*N; k++){ array[k]=0.; }
    return *this;
  }
  dgematrix_small<M,N>& identity(){
    zero();
    for(long k=0; k<std::min(M,N); k++){ (*this)(k,k)=1.; }
    return *this;
  }
  dgematrix_small<M,N>& set(const long& i, const long& j, const double& v){
    (*this)(i,j)=v;
    return *this;
  }  
  
  dcovector_small<M> col(const long& j) const{
    dcovector_small<M> vec;
    for(long i=0; i<M; i++){ vec(i)=(*this)(i,j); }
    return vec;
  }
  
  drovector_small<N> row(const long& i) const{
    drovector_small<N> vec;
    for(long j=0; j<N; j++){ vec(j)=(*this)(i,j); }
    return vec;
  }
  
  void write(const char* filename) const;
  void read(const char* filename);
  
  _dgematrix to_dgematrix() const{
    dgematrix mat(M,N);
    for(long i=0; i<M; i++){
      for(long j=0; j<N; j++){
        mat(i,j)=(*this)(i,j);
      }
    }
    return _(mat);
  }
};