Class Cols

tables/table.py:3244–3510

Container for columns in a table or nested column. This class is used as an *accessor* to the columns in a table or nested column. It supports the *natural naming* convention, so that you can access the different columns as attributes which lead to Column instances (for non-nested

class Cols:
    """Container for columns in a table or nested column.

    This class is used as an *accessor* to the columns in a table or nested
    column.  It supports the *natural naming* convention, so that you can
    access the different columns as attributes which lead to Column instances
    (for non-nested columns) or other Cols instances (for nested columns).

    For instance, if table.cols is a Cols instance with a column named col1
    under it, the later can be accessed as table.cols.col1. If col1 is nested
    and contains a col2 column, this can be accessed as table.cols.col1.col2
    and so on. Because of natural naming, the names of members start with
    special prefixes, like in the Group class (see :ref:`GroupClassDescr`).

    Like the Column class (see :ref:`ColumnClassDescr`), Cols supports item
    access to read and write ranges of values in the table or nested column.


    .. rubric:: Cols attributes

    .. attribute:: _v_colnames

        A list of the names of the columns hanging directly
        from the associated table or nested column.  The order of
        the names matches the order of their respective columns in
        the containing table.

    .. attribute:: _v_colpathnames

        A list of the pathnames of all the columns under the
        associated table or nested column (in preorder).  If it does
        not contain nested columns, this is exactly the same as the
        :attr:`Cols._v_colnames` attribute.

    .. attribute:: _v_desc

        The associated Description instance (see
        :ref:`DescriptionClassDescr`).

    """

    @property
    def _v_table(self) -> Table:
        """Return the parent Table instance (see :ref:`TableClassDescr`)."""
        return self._v__tableFile._get_node(self._v__tablePath)

    def __init__(self, table: Table, desc: Description) -> None:
        dict_ = self.__dict__
        dict_["_v__tableFile"] = table._v_file
        dict_["_v__tablePath"] = table._v_pathname
        dict_["_v_desc"] = desc
        dict_["_v_colnames"] = desc._v_names
        dict_["_v_colpathnames"] = table.description._v_pathnames
        # Put the column in the local dictionary
        for name in desc._v_names:
            if name in desc._v_types:
                dict_[name] = Column(table, name, desc)
            else: