class_docstr: base matrix class for compressed row and column oriented matrices
class_docstr_tok: ["base","matrix","class","for","compressed","row","and","column","oriented","matrices"]
code: def _add_dense(self, other):
      if other.shape != self.shape:
          raise ValueError("Incompatible shapes.")
      dtype = upcast_char(self.dtype.char, other.dtype.char)
      order = self._swap("CF")[0]
      result = np.array(other, dtype=dtype, order=order, copy=True)
      M, N = self._swap(self.shape)
      y = result if result.flags.c_contiguous else result.T
      _sparsetools.csr_todense(
          M, N, self.indptr, self.indices, self.data, y
      )
      return matrix(result, copy=False)
  
imports: from __future__ import division, print_function, absolute_import
  from warnings import warn
  import operator
  import numpy
  from scipy._lib.six import zip
  from scipy._lib._util import _prune_array
  from .base import spmatrix, isspmatrix, SparseEfficiencyWarning
  from .data import _data_matrix, _minmax_mixin
  from .dia import dia_matrix
  from .None import _sparsetools
  from .sputils import upcast, upcast_char, to_native, isdense, isshape, getdtype, isscalarlike, IndexMixin, get_index_dtype, downcast_intp_index, get_sum_dtype, check_shape, matrix, asmatrix
label_desc: Use image node_id 13 for calling the _cs_matrix obj's underlying member method code with example usage: obj._add_dense(other) and returns: matrix