nlte.py 文件源码

def neighbours(self, effective_temperature, surface_gravity, metallicity, N,
        scales=None):
        """
        Return indices of the `N`th-nearest neighbours in the grid. The three
        parameters are scaled by the peak-to-peak range in the grid, unless
        `scales` are indicates.

        :param effective_temperature:
            The effective temperature of the star.

        :param surface_gravity:
            The surface gravity of the star.

        :param metallicity:
            The metallicity of the star.

        :param N:
            The number of neighbouring indices to return.

        :returns:
            An array of length `N` that contains the indices of the closest
            neighbours in the grid.
        """

        point = np.array([effective_temperature, surface_gravity, metallicity])
        if scales is None:
            scales = np.ptp(self._grid, axis=0)

        distance = np.sum(((self._grid - point)/scales)**2, axis=1)

        return np.argsort(distance)[:N]