csr(4rheolef) csr(4rheolef)

csr - distributed compressed sparse matrix (rheolef-7.2)

Sparse matrix are compressed by rows. In a distributed environment, the distribution follows the row distributor(4).

This class supports the standard linear algebra. Adding or subtracting two matrices simply writes a+b and a-b, respectively. Multiplying a matrix by a scalar writes lambda*a and the matrix-matrix product also writes a*b. Matrix-vector product expresses a*x where x is a vector described by the vec(4) class.

By extension, trans(a) returns the transpose. Multiplying a vector by the transpose matrix writes a.trans_mult(x) and do not requires to build the transpose matrix.

This documentation has been generated from file linalg/lib/csr.h

The csr class is a template class with both the floating type and the memory model as parameters. Here is the interface for the sequential memory model. The distributed case presents a similar interface.

template<class T>
class csr<T,sequential> : public smart_pointer<csr_rep<T,sequential> > {
public:
// typedefs:
    typedef csr_rep<T,sequential>             rep;
    typedef smart_pointer<rep>                base;
    typedef typename rep::memory_type         memory_type;
    typedef typename rep::size_type           size_type;
    typedef typename rep::element_type        element_type;
    typedef typename rep::iterator            iterator;
    typedef typename rep::const_iterator      const_iterator;
    typedef typename rep::data_iterator       data_iterator;
    typedef typename rep::const_data_iterator const_data_iterator;
// allocators/deallocators:
    csr() : base(new_macro(rep())) {}
    template<class A>
    explicit csr(const asr<T,sequential,A>& a) : base(new_macro(rep(a))) {}
    void resize (size_type loc_nrow1 = 0, size_type loc_ncol1 = 0, size_type loc_nnz1 = 0)
        { base::data().resize(loc_nrow1, loc_ncol1, loc_nnz1); }
    void resize (const distributor& row_ownership, const distributor& col_ownership, size_type nnz1 = 0)
        { base::data().resize(row_ownership, col_ownership, nnz1); }
// allocators from initializer list
    csr (const std::initializer_list<details::csr_concat_value<T,sequential> >& init_list);
    csr (const std::initializer_list<details::csr_concat_line<T,sequential> >&  init_list);
// accessors:
    // global sizes
    const distributor& row_ownership() const { return base::data().row_ownership(); }
    const distributor& col_ownership() const { return base::data().col_ownership(); }
    size_type dis_nrow () const              { return row_ownership().dis_size(); }
    size_type dis_ncol () const              { return col_ownership().dis_size(); }
    size_type dis_nnz () const               { return base::data().nnz(); }
    size_type dis_ext_nnz () const           { return 0; }
    bool is_symmetric() const                { return base::data().is_symmetric(); }
    void set_symmetry (bool is_symm) const   { base::data().set_symmetry(is_symm); }
    void set_symmetry_by_check (const T& tol = std::numeric_limits<T>::epsilon()) const
                                             { base::data().set_symmetry_by_check(); }
    bool is_definite_positive() const        { return base::data().is_definite_positive(); }
    void set_definite_positive (bool is_defpos) const { base::data().set_definite_positive(is_defpos); }
    size_type pattern_dimension() const      { return base::data().pattern_dimension(); }
    void set_pattern_dimension(size_type dim) const { base::data().set_pattern_dimension(dim); }
    T max_abs () const                       { return base::data().max_abs(); }
    // local sizes
    size_type nrow () const                  { return base::data().nrow(); }
    size_type ncol () const                  { return base::data().ncol(); }
    size_type nnz () const                   { return base::data().nnz(); }
    
    // range on local memory
    size_type row_first_index () const       { return base::data().row_first_index(); }
    size_type row_last_index () const        { return base::data().row_last_index(); }
    size_type col_first_index () const       { return base::data().col_first_index(); }
    size_type col_last_index () const        { return base::data().col_last_index(); }
    const_iterator begin() const             { return base::data().begin(); }
    const_iterator end()   const             { return base::data().end(); }
    iterator begin_nonconst()                { return base::data().begin(); }
    iterator end_nonconst()                  { return base::data().end(); }
    // accessors, only for distributed (for interface compatibility)
    size_type ext_nnz() const                { return 0; }
    const_iterator ext_begin() const         { return const_iterator(); }
    const_iterator ext_end()   const         { return const_iterator(); }
          iterator ext_begin_nonconst()      { return iterator(); }
          iterator ext_end_nonconst()        { return iterator(); }
    size_type jext2dis_j (size_type jext) const { return 0; }
    int constraint_process_rank() const;
// algebra:
    // y := a*x
    void mult (const vec<element_type,sequential>& x, vec<element_type,sequential>& y) const {
      base::data().mult (x,y);
    }
    vec<element_type,sequential> operator* (const vec<element_type,sequential>& x) const {
      vec<element_type,sequential> y (row_ownership(), element_type());
      mult (x, y);
      return y;
    }
    void trans_mult (const vec<element_type,sequential>& x, vec<element_type,sequential>& y) const {
      base::data().trans_mult (x,y);
    }
    vec<element_type,sequential> trans_mult (const vec<element_type,sequential>& x) const {
      vec<element_type,sequential> y (col_ownership(), element_type());
      trans_mult (x, y);
      return y;
    }
    // a+b, a-b, a*b
    csr<T,sequential> operator+ (const csr<T,sequential>& b) const;
    csr<T,sequential> operator- (const csr<T,sequential>& b) const;
    csr<T,sequential> operator* (const csr<T,sequential>& b) const;
    // lambda*a
    csr<T,sequential>& operator*= (const T& lambda) {
      base::data().operator*= (lambda);
      return *this;
    }
// output:
    void dump (const std::string& name) const { base::data().dump(name); }
};

Pierre Saramito <Pierre.Saramito@imag.fr>

Copyright (C) 2000-2018 Pierre Saramito <Pierre.Saramito@imag.fr> GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>. This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.

Version 7.2 rheolef