TsparseMatrix-class          package:Matrix          R Documentation

_C_l_a_s_s "_T_s_p_a_r_s_e_M_a_t_r_i_x" _o_f _S_p_a_r_s_e _M_a_t_r_i_c_e_s _i_n _T_r_i_p_l_e_t _F_o_r_m

_D_e_s_c_r_i_p_t_i_o_n:

     The '"TsparseMatrix"' class is the virtual class of all sparse
     matrices coded in triplet form.  Since it is a virtual class, no
     objects may be created from it.  See 'showClass("TsparseMatrix")'
     for its subclasses.

_S_l_o_t_s:


     '_D_i_m', '_D_i_m_n_a_m_e_s': from the '"Matrix"' class,

     '_i': Object of class '"integer"' - the row indices of non-zero
          entries _in 0-base_, i.e., must be in '0:(nrow(.)-1)'.

     '_j': Object of class '"integer"' - the column indices of non-zero
          entries.  Must be the same length as slot 'i' and _0-based_
          as well, i.e., in '0:(ncol(.)-1)'.   For numeric Tsparse
          matrices, '(i,j)' pairs can occur more than once, see
          'dgTMatrix'.


_E_x_t_e_n_d_s:

     Class '"sparseMatrix"', directly. Class '"Matrix"', by class
     '"sparseMatrix"'.

_M_e_t_h_o_d_s:

     Extraction ('"["') methods, see '[-methods'.

_N_o_t_e:

     Most operations with sparse matrices are performed using the
     compressed, column-oriented or 'CsparseMatrix' representation. 
     The triplet representation is convenient for creating a sparse
     matrix or for reading and writing such matrices.  Once it is
     created, however, the matrix is generally coerced to a
     'CsparseMatrix' for further operations.

     For convenience, methods for some operations such as '%*%' and
     'crossprod' are defined for 'TsparseMatrix' objects.  These
     methods simply coerce the 'TsparseMatrix' object to a
     'CsparseMatrix' object then perform the operation.

_S_e_e _A_l_s_o:

     its superclass, 'sparseMatrix', and the 'dgTMatrix' class, for the
     links to other classes.

_E_x_a_m_p_l_e_s:

     showClass("TsparseMatrix")
     ## or just the subclasses' names
     names(getClass("TsparseMatrix")@subclasses)