Method append

tables/table.py:2333–2401

Append a sequence of rows to the end of the table. The rows argument may be any object which can be converted to a structured array compliant with the table structure (otherwise, a ValueError is raised). This includes NumPy structured arrays, lists of tuples or arra

(self, rows: list | np.ndarray)

                self._mark_columns_as_dirty(self.colpathnames)

    def append(self, rows: list | np.ndarray) -> None:
        """Append a sequence of rows to the end of the table.

        The rows argument may be any object which can be converted to
        a structured array compliant with the table structure
        (otherwise, a ValueError is raised).  This includes NumPy
        structured arrays, lists of tuples or array records, and a
        string or Python buffer.

        Examples
        --------
        ::

            import tables as tb

            class Particle(tb.IsDescription):
                name        = tb.StringCol(16, pos=1) # 16-character String
                lati        = tb.IntCol(pos=2)        # integer
                longi       = tb.IntCol(pos=3)        # integer
                pressure    = tb.Float32Col(pos=4)  # float  (single-precision)
                temperature = tb.FloatCol(pos=5)    # double (double-precision)

            fileh = tb.open_file('test4.h5', mode='w')
            table = fileh.create_table(fileh.root, 'table', Particle,
                                       "A table")

            # Append several rows in only one call
            table.append([("Particle:     10", 10, 0, 10 * 10, 10**2),
                          ("Particle:     11", 11, -1, 11 * 11, 11**2),
                          ("Particle:     12", 12, -2, 12 * 12, 12**2)])
            fileh.close()

        """
        self._g_check_open()
        self._v_file._check_writable()

        if not self._chunked:
            raise HDF5ExtError(
                "You cannot append rows to a non-chunked table.", h5bt=False
            )

        if (
            hasattr(rows, "dtype")
            and not self.description._v_is_nested
            and rows.dtype == self.dtype
        ):
            # Shortcut for compliant arrays
            # (for some reason, not valid for nested types)
            wbuf_ra = rows
        else:
            # Try to convert the object into a recarray compliant with table
            try:
                iflavor = flavor_of(rows)
                if iflavor != "python":
                    rows = array_as_internal(rows, iflavor)
                # Works for Python structures and always copies the original,
                # so the resulting object is safe for in-place conversion.
                wbuf_ra = np.rec.array(rows, dtype=self._v_dtype)