cs_matrix initializer

compressed.py

class _cs_matrix(_data_matrix, _minmax_mixin, IndexMixin):
    """base matrix class for compressed row and column oriented matrices"""

    def __init__(self, arg1, shape=None, dtype=None, copy=False):
        _data_matrix.__init__(self)

        if isspmatrix(arg1):
            ...

        elif isinstance(arg1, tuple):
            ...

        else:
            # must be dense
            try:
                arg1 = np.asarray(arg1)
            except Exception:
                raise ValueError("unrecognized {}_matrix constructor usage"
                                 "".format(self.format))
            from .coo import coo_matrix
            self._set_self(self.__class__(coo_matrix(arg1, dtype=dtype)))

        # Read matrix dimensions given, if any
        if shape is not None:
            self._shape = check_shape(shape)
        else:
            ...

        self.check_format(full_check=False)