def agedepth(self, d):
        """Get calendar age for a depth

        Parameters
        ----------
        d : float
            Sediment depth (in cm).

        Returns
        -------
        Numeric giving true age at given depth.
        """
        # TODO(brews): Function cannot handle hiatus
        # See lines 77 - 100 of hist2.cpp
        x = self.mcmcfit.sediment_rate
        theta0 = self.mcmcfit.headage  # Age abscissa (in yrs).  If array, dimension should be iterations or realizations of the sediment
        deltac = self.thick
        c0 = min(self.depth)  # Uniform depth segment abscissa (in cm).
        assert d > c0 or np.isclose(c0, d, atol = 1e-4)
        out = theta0.astype(float)
        i = int(np.floor((d - c0) / deltac))
        for j in range(i):
            out += x[j] * deltac
        ci = c0 + i * deltac
        assert ci < d or np.isclose(ci, d, atol = 1e-4)
        try:
            next_x = x[i]
        except IndexError:
            # Extrapolating
            next_x = x[i - 1]
        out += next_x * (d - ci)
        return out
Get calendar age for a depth

        Parameters
        ----------
        d : float
            Sediment depth (in cm).

        Returns
        -------
        Numeric giving true age at given depth.