Class DateConverter

lib/matplotlib/dates.py:1728–1786

Converter for `datetime.date` and `datetime.datetime` data, or for date/time data represented as it would be converted by `date2num`. The 'unit' tag for such data is None or a `~datetime.tzinfo` instance.

class DateConverter(units.ConversionInterface):
    """
    Converter for `datetime.date` and `datetime.datetime` data, or for
    date/time data represented as it would be converted by `date2num`.

    The 'unit' tag for such data is None or a `~datetime.tzinfo` instance.
    """

    def __init__(self, *, interval_multiples=True):
        self._interval_multiples = interval_multiples
        super().__init__()

    def axisinfo(self, unit, axis):
        """
        Return the `~matplotlib.units.AxisInfo` for *unit*.

        *unit* is a `~datetime.tzinfo` instance or None.
        The *axis* argument is required but not used.
        """
        tz = unit

        majloc = AutoDateLocator(tz=tz,
                                 interval_multiples=self._interval_multiples)
        majfmt = AutoDateFormatter(majloc, tz=tz)
        datemin = datetime.date(1970, 1, 1)
        datemax = datetime.date(1970, 1, 2)

        return units.AxisInfo(majloc=majloc, majfmt=majfmt, label='',
                              default_limits=(datemin, datemax))

    @staticmethod
    def convert(value, unit, axis):
        """
        If *value* is not already a number or sequence of numbers, convert it
        with `date2num`.

        The *unit* and *axis* arguments are not used.
        """
        return date2num(value)

    @staticmethod
    def default_units(x, axis):
        """
        Return the `~datetime.tzinfo` instance of *x* or of its first element,
        or None
        """
        if isinstance(x, np.ndarray):
            x = x.ravel()

        try:
            x = cbook._safe_first_finite(x)
        except (TypeError, StopIteration):
            pass

        try:
            return x.tzinfo
        except AttributeError:
            pass