コード例 #1
0
    def predict(self, shower_seed, energy_seed):
        """Predict method for the ImPACT reconstructor.
        Used to calculate the reconstructed ImPACT shower geometry and energy.

        Parameters
        ----------
        shower_seed: ReconstructedShowerContainer
            Seed shower geometry to be used in the fit
        energy_seed: ReconstructedEnergyContainer
            Seed energy to be used in fit

        Returns
        -------
        ReconstructedShowerContainer, ReconstructedEnergyContainer:
        """
        self.reset_interpolator()

        horizon_seed = SkyCoord(az=shower_seed.az, alt=shower_seed.alt, frame=AltAz())
        nominal_seed = horizon_seed.transform_to(self.nominal_frame)

        source_x = nominal_seed.fov_lon.to_value(u.rad)
        source_y = nominal_seed.fov_lat.to_value(u.rad)
        ground = GroundFrame(x=shower_seed.core_x, y=shower_seed.core_y, z=0 * u.m)
        tilted = ground.transform_to(
            TiltedGroundFrame(pointing_direction=self.array_direction)
        )
        tilt_x = tilted.x.to(u.m).value
        tilt_y = tilted.y.to(u.m).value
        zenith = 90 * u.deg - self.array_direction.alt

        seeds = spread_line_seed(
            self.hillas_parameters,
            self.tel_pos_x,
            self.tel_pos_y,
            source_x,
            source_y,
            tilt_x,
            tilt_y,
            energy_seed.energy.value,
            shift_frac=[1],
        )[0]

        # Perform maximum likelihood fit
        fit_params, errors, like = self.minimise(
            params=seeds[0],
            step=seeds[1],
            limits=seeds[2],
            minimiser_name=self.minimiser_name,
        )

        # Create a container class for reconstructed shower
        shower_result = ReconstructedShowerContainer()

        # Convert the best fits direction and core to Horizon and ground systems and
        # copy to the shower container
        nominal = SkyCoord(
            fov_lon=fit_params[0] * u.rad,
            fov_lat=fit_params[1] * u.rad,
            frame=self.nominal_frame,
        )
        horizon = nominal.transform_to(AltAz())

        shower_result.alt, shower_result.az = horizon.alt, horizon.az
        tilted = TiltedGroundFrame(
            x=fit_params[2] * u.m,
            y=fit_params[3] * u.m,
            pointing_direction=self.array_direction,
        )
        ground = project_to_ground(tilted)

        shower_result.core_x = ground.x
        shower_result.core_y = ground.y

        shower_result.is_valid = True

        # Currently no errors not available to copy NaN
        shower_result.alt_uncert = np.nan
        shower_result.az_uncert = np.nan
        shower_result.core_uncert = np.nan

        # Copy reconstructed Xmax
        shower_result.h_max = fit_params[5] * self.get_shower_max(
            fit_params[0],
            fit_params[1],
            fit_params[2],
            fit_params[3],
            zenith.to(u.rad).value,
        )

        shower_result.h_max *= np.cos(zenith)
        shower_result.h_max_uncert = errors[5] * shower_result.h_max

        shower_result.goodness_of_fit = like

        # Create a container class for reconstructed energy
        energy_result = ReconstructedEnergyContainer()
        # Fill with results
        energy_result.energy = fit_params[4] * u.TeV
        energy_result.energy_uncert = errors[4] * u.TeV
        energy_result.is_valid = True

        return shower_result, energy_result
コード例 #2
0
    def predict(self,
                hillas_dict,
                inst,
                array_pointing,
                telescopes_pointings=None):
        """
        The function you want to call for the reconstruction of the
        event. It takes care of setting up the event and consecutively
        calls the functions for the direction and core position
        reconstruction.  Shower parameters not reconstructed by this
        class are set to np.nan

        Parameters
        -----------
        hillas_dict: dict
            dictionary with telescope IDs as key and
            HillasParametersContainer instances as values
        inst : ctapipe.io.InstrumentContainer
            instrumental description
        array_pointing: SkyCoord[AltAz]
            pointing direction of the array
        telescopes_pointings: dict[SkyCoord[AltAz]]
            dictionary of pointing direction per each telescope

        Raises
        ------
        TooFewTelescopesException
            if len(hillas_dict) < 2
        InvalidWidthException
            if any width is np.nan or 0
        """

        # filter warnings for missing obs time. this is needed because MC data has no obs time
        warnings.filterwarnings(action='ignore',
                                category=MissingFrameAttributeWarning)

        # stereoscopy needs at least two telescopes
        if len(hillas_dict) < 2:
            raise TooFewTelescopesException(
                "need at least two telescopes, have {}".format(
                    len(hillas_dict)))

        # check for np.nan or 0 width's as these screw up weights
        if any(
            [np.isnan(hillas_dict[tel]['width'].value)
             for tel in hillas_dict]):
            raise InvalidWidthException(
                "A HillasContainer contains an ellipse of width==np.nan")

        if any([hillas_dict[tel]['width'].value == 0 for tel in hillas_dict]):
            raise InvalidWidthException(
                "A HillasContainer contains an ellipse of width==0")

        # use the single telescope pointing also for parallel pointing: code is more general
        if telescopes_pointings is None:
            telescopes_pointings = {
                tel_id: array_pointing
                for tel_id in hillas_dict.keys()
            }
        else:
            self.divergent_mode = True
            self.corrected_angle_dict = {}

        self.initialize_hillas_planes(hillas_dict, inst.subarray,
                                      telescopes_pointings, array_pointing)

        # algebraic direction estimate
        direction, err_est_dir = self.estimate_direction()

        # array pointing is needed to define the tilted frame
        core_pos = self.estimate_core_position(hillas_dict, array_pointing)

        # container class for reconstructed showers
        result = ReconstructedShowerContainer()
        _, lat, lon = cartesian_to_spherical(*direction)

        # estimate max height of shower
        h_max = self.estimate_h_max()

        # astropy's coordinates system rotates counter-clockwise.
        # Apparently we assume it to be clockwise.
        result.alt, result.az = lat, -lon
        result.core_x = core_pos[0]
        result.core_y = core_pos[1]
        result.core_uncert = np.nan

        result.tel_ids = [h for h in hillas_dict.keys()]
        result.average_intensity = np.mean(
            [h.intensity for h in hillas_dict.values()])
        result.is_valid = True

        result.alt_uncert = err_est_dir
        result.az_uncert = np.nan

        result.h_max = h_max
        result.h_max_uncert = np.nan

        result.goodness_of_fit = np.nan

        return result
コード例 #3
0
    def predict(self, hillas_dict, inst, array_pointing, telescopes_pointings=None):
        """

        Parameters
        ----------
        hillas_dict: dict
            Dictionary containing Hillas parameters for all telescopes
            in reconstruction
        inst : ctapipe.io.InstrumentContainer
            instrumental description
        array_pointing: SkyCoord[AltAz]
            pointing direction of the array
        telescopes_pointings: dict[SkyCoord[AltAz]]
            dictionary of pointing direction per each telescope

        Returns
        -------
        ReconstructedShowerContainer:

        """

        # filter warnings for missing obs time. this is needed because MC data has no obs time
        warnings.filterwarnings(action='ignore', category=MissingFrameAttributeWarning)

        # stereoscopy needs at least two telescopes
        if len(hillas_dict) < 2:
            raise TooFewTelescopesException(
                "need at least two telescopes, have {}"
                .format(len(hillas_dict)))

        # check for np.nan or 0 width's as these screw up weights
        if any([np.isnan(hillas_dict[tel]['width'].value) for tel in hillas_dict]):
            raise InvalidWidthException(
                "A HillasContainer contains an ellipse of width==np.nan")

        if any([hillas_dict[tel]['width'].value == 0 for tel in hillas_dict]):
            raise InvalidWidthException(
                "A HillasContainer contains an ellipse of width==0")

        if telescopes_pointings is None:
            telescopes_pointings = {tel_id: array_pointing for tel_id in hillas_dict.keys()}

        tilted_frame = TiltedGroundFrame(pointing_direction=array_pointing)

        ground_positions = inst.subarray.tel_coords
        grd_coord = GroundFrame(x=ground_positions.x,
                                y=ground_positions.y,
                                z=ground_positions.z)

        tilt_coord = grd_coord.transform_to(tilted_frame)

        tel_x = {tel_id: tilt_coord.x[tel_id-1] for tel_id in list(hillas_dict.keys())}
        tel_y = {tel_id: tilt_coord.y[tel_id-1] for tel_id in list(hillas_dict.keys())}

        nom_frame = NominalFrame(origin=array_pointing)

        hillas_dict_mod = copy.deepcopy(hillas_dict)

        for tel_id, hillas in hillas_dict_mod.items():
            # prevent from using rads instead of meters as inputs
            assert hillas.x.to(u.m).unit == u.Unit('m')

            focal_length = inst.subarray.tel[tel_id].optics.equivalent_focal_length

            camera_frame = CameraFrame(
                telescope_pointing=telescopes_pointings[tel_id],
                focal_length=focal_length,
            )
            cog_coords = SkyCoord(x=hillas.x, y=hillas.y, frame=camera_frame)
            cog_coords_nom = cog_coords.transform_to(nom_frame)
            hillas.x = cog_coords_nom.delta_alt
            hillas.y = cog_coords_nom.delta_az

        src_x, src_y, err_x, err_y = self.reconstruct_nominal(hillas_dict_mod)
        core_x, core_y, core_err_x, core_err_y = self.reconstruct_tilted(
            hillas_dict_mod, tel_x, tel_y)

        err_x *= u.rad
        err_y *= u.rad

        nom = SkyCoord(
            delta_az=src_x * u.rad,
            delta_alt=src_y * u.rad,
            frame=nom_frame
        )
        # nom = sky_pos.transform_to(nom_frame)
        sky_pos = nom.transform_to(array_pointing.frame)

        result = ReconstructedShowerContainer()
        result.alt = sky_pos.altaz.alt.to(u.rad)
        result.az = sky_pos.altaz.az.to(u.rad)

        tilt = SkyCoord(
            x=core_x * u.m,
            y=core_y * u.m,
            frame=tilted_frame,
        )
        grd = project_to_ground(tilt)
        result.core_x = grd.x
        result.core_y = grd.y

        x_max = self.reconstruct_xmax(
            nom.delta_az,
            nom.delta_alt,
            tilt.x, tilt.y,
            hillas_dict_mod,
            tel_x, tel_y,
            90 * u.deg - array_pointing.alt,
        )

        result.core_uncert = np.sqrt(core_err_x**2 + core_err_y**2) * u.m

        result.tel_ids = [h for h in hillas_dict_mod.keys()]
        result.average_intensity = np.mean([h.intensity for h in hillas_dict_mod.values()])
        result.is_valid = True

        src_error = np.sqrt(err_x**2 + err_y**2)
        result.alt_uncert = src_error.to(u.rad)
        result.az_uncert = src_error.to(u.rad)
        result.h_max = x_max
        result.h_max_uncert = np.nan
        result.goodness_of_fit = np.nan

        return result