def interp_calendar(
        self,
        target: pd.DatetimeIndex | CFTimeIndex | DataArray,
        dim: str = "time",
    ) -> Self:
        """Interpolates the DataArray to another calendar based on decimal year measure.

        Each timestamp in `source` and `target` are first converted to their decimal
        year equivalent then `source` is interpolated on the target coordinate.
        The decimal year of a timestamp is its year plus its sub-year component
        converted to the fraction of its year. For example "2000-03-01 12:00" is
        2000.1653 in a standard calendar or 2000.16301 in a `"noleap"` calendar.

        This method should only be used when the time (HH:MM:SS) information of
        time coordinate is not important.

        Parameters
        ----------
        target: DataArray or DatetimeIndex or CFTimeIndex
            The target time coordinate of a valid dtype
            (np.datetime64 or cftime objects)
        dim : str
            The time coordinate name.

        Return
        ------
        DataArray
            The source interpolated on the decimal years of target,
        """
        return interp_calendar(self, target, dim=dim)
Interpolates the DataArray to another calendar based on decimal year measure.

        Each timestamp in `source` and `target` are first converted to their decimal
        year equivalent then `source` is interpolated on the target coordinate.
        The decimal year of a timestamp is its year plus its sub-year component
        converted to the fraction of its year. For example "2000-03-01 12:00" is
        2000.1653 in a standard calendar or 2000.16301 in a `"noleap"` calendar.

        This method should only be used when the time (HH:MM:SS) information of
        time coordinate is not important.

        Parameters
        ----------
        target: DataArray or DatetimeIndex or CFTimeIndex
            The target time coordinate of a valid dtype
            (np.datetime64 or cftime objects)
        dim : str
            The time coordinate name.

        Return
        ------
        DataArray
            The source interpolated on the decimal years of target,
        
xarray/core/dataarray.py