Source code for gammapy.estimators.points.core

# Licensed under a 3-clause BSD style license - see LICENSE.rst
import logging
from copy import deepcopy
import numpy as np
from scipy import stats
from scipy.interpolate import interp1d
from scipy.optimize import minimize
from astropy.io import fits
from astropy.io.registry import IORegistryError
from astropy.table import Table, vstack
from astropy.time import Time
from astropy.visualization import quantity_support
import matplotlib.pyplot as plt
from gammapy.data import GTI
from gammapy.maps import Map, MapAxis, Maps, RegionNDMap, TimeMapAxis
from gammapy.maps.axes import UNIT_STRING_FORMAT, flat_if_equal
from gammapy.modeling.models import TemplateSpectralModel
from gammapy.modeling.models.spectral import scale_plot_flux
from gammapy.modeling.scipy import stat_profile_ul_scipy
from gammapy.utils.interpolation import interpolate_profile
from gammapy.utils.scripts import make_path
from gammapy.utils.table import table_standardise_units_copy
from gammapy.utils.time import time_ref_to_dict
from ..map.core import DEFAULT_UNIT, FluxMaps

__all__ = ["FluxPoints"]

log = logging.getLogger(__name__)


def squash_fluxpoints(flux_point, axis):
    """Squash a FluxPoints object into one point.
    The log-likelihoods profiles in each bin are summed
    to compute the resultant quantities. Stat profiles
    must be present on the fluxpoints object for
    this method to work.
    """

    value_scan = flux_point.stat_scan.geom.axes["norm"].center
    stat_scan = np.sum(flux_point.stat_scan.data, axis=0).ravel()
    f = interp1d(value_scan, stat_scan, kind="quadratic", bounds_error=False)
    f = interpolate_profile(value_scan, stat_scan)
    minimizer = minimize(
        f,
        x0=value_scan[
            int(len(value_scan) / 2),
        ],
        bounds=[(value_scan[0], value_scan[-1])],
        method="L-BFGS-B",
    )

    maps = Maps()
    geom = flux_point.geom.to_image()
    if axis.name != "energy":
        geom = geom.to_cube([flux_point.geom.axes["energy"]])

    maps["norm"] = Map.from_geom(geom, data=minimizer.x)
    maps["norm_err"] = Map.from_geom(geom, data=np.sqrt(minimizer.hess_inv.todense()))
    maps["n_dof"] = Map.from_geom(geom, data=flux_point.geom.axes[axis.name].nbin)

    if "norm_ul" in flux_point.available_quantities:
        delta_ts = flux_point.meta.get("n_sigma_ul", 2) ** 2
        ul = stat_profile_ul_scipy(value_scan, stat_scan, delta_ts=delta_ts)
        maps["norm_ul"] = Map.from_geom(geom, data=ul.value)

    maps["stat"] = Map.from_geom(geom, data=f(minimizer.x))

    maps["stat_scan"] = Map.from_geom(
        geom=geom.to_cube([MapAxis.from_nodes(value_scan, name="norm")]), data=stat_scan
    )
    try:
        maps["stat_null"] = Map.from_geom(geom, data=np.sum(flux_point.stat_null.data))
        maps["ts"] = maps["stat_null"] - maps["stat"]
    except AttributeError:
        log.info(
            "Stat null info not present on original FluxPoints object. TS not computed"
        )

    maps["success"] = Map.from_geom(geom=geom, data=minimizer.success, dtype=bool)

    combined_fp = FluxPoints.from_maps(
        maps=maps,
        sed_type=flux_point.sed_type_init,
        reference_model=flux_point.reference_model,
        gti=flux_point.gti,
        meta=flux_point.meta,
    )
    return combined_fp


[docs]class FluxPoints(FluxMaps): """Flux points container. The supported formats are described here: :ref:`gadf:flux-points`. In summary, the following formats and minimum required columns are: * Format ``dnde``: columns ``e_ref`` and ``dnde`` * Format ``e2dnde``: columns ``e_ref``, ``e2dnde`` * Format ``flux``: columns ``e_min``, ``e_max``, ``flux`` * Format ``eflux``: columns ``e_min``, ``e_max``, ``eflux`` Parameters ---------- table : `~astropy.table.Table` Table with flux point data. Attributes ---------- table : `~astropy.table.Table` Table with flux point data. Examples -------- The `FluxPoints` object is most easily created by reading a file with flux points given in one of the formats documented above:: >>> from gammapy.estimators import FluxPoints >>> filename = '$GAMMAPY_DATA/hawc_crab/HAWC19_flux_points.fits' >>> flux_points = FluxPoints.read(filename) >>> flux_points.plot() #doctest: +SKIP An instance of `FluxPoints` can also be created by passing an instance of `astropy.table.Table`, which contains the required columns, such as `'e_ref'` and `'dnde'`. The corresponding `sed_type` has to be defined in the meta data of the table:: >>> import numpy as np >>> from astropy import units as u >>> from astropy.table import Table >>> from gammapy.estimators import FluxPoints >>> from gammapy.modeling.models import PowerLawSpectralModel >>> table = Table() >>> pwl = PowerLawSpectralModel() >>> e_ref = np.geomspace(1, 100, 7) * u.TeV >>> table["e_ref"] = e_ref >>> table["dnde"] = pwl(e_ref) >>> table["dnde_err"] = pwl.evaluate_error(e_ref)[0] >>> table.meta["SED_TYPE"] = "dnde" >>> flux_points = FluxPoints.from_table(table) >>> flux_points.plot(sed_type="flux") #doctest: +SKIP If you have flux points in a different data format, the format can be changed by renaming the table columns and adding meta data:: >>> from astropy import units as u >>> from astropy.table import Table >>> from gammapy.estimators import FluxPoints >>> from gammapy.utils.scripts import make_path >>> filename = make_path('$GAMMAPY_DATA/tests/spectrum/flux_points/flux_points_ctb_37b.txt') >>> table = Table.read(filename ,format='ascii.csv', delimiter=' ', comment='#') >>> table.rename_column('Differential_Flux', 'dnde') >>> table['dnde'].unit = 'cm-2 s-1 TeV-1' >>> table.rename_column('lower_error', 'dnde_errn') >>> table['dnde_errn'].unit = 'cm-2 s-1 TeV-1' >>> table.rename_column('upper_error', 'dnde_errp') >>> table['dnde_errp'].unit = 'cm-2 s-1 TeV-1' >>> table.rename_column('E', 'e_ref') >>> table['e_ref'].unit = 'TeV' >>> flux_points = FluxPoints.from_table(table, sed_type="dnde") >>> flux_points.plot(sed_type="e2dnde") #doctest: +SKIP Note: In order to reproduce the example you need the tests datasets folder. You may download it with the command ``gammapy download datasets --tests --out $GAMMAPY_DATA`` """
[docs] @classmethod def read( cls, filename, sed_type=None, format=None, reference_model=None, checksum=False, **kwargs, ): """Read precomputed flux points. Parameters ---------- filename : str Filename. sed_type : {"dnde", "flux", "eflux", "e2dnde", "likelihood"} SED type. format : {"gadf-sed", "lightcurve", "profile"}, optional Format string. If None, the format is extracted from the input. Default is None. reference_model : `SpectralModel` Reference spectral model. checksum : bool If True checks both DATASUM and CHECKSUM cards in the file headers. Default is False. **kwargs : dict, optional Keyword arguments passed to `astropy.table.Table.read`. Returns ------- flux_points : `FluxPoints` Flux points. """ filename = make_path(filename) gti = None kwargs.setdefault("format", "ascii.ecsv") try: table = Table.read(filename, **kwargs) except (IORegistryError, UnicodeDecodeError): with fits.open(filename, checksum=checksum) as hdulist: if "FLUXPOINTS" in hdulist: fp = hdulist["FLUXPOINTS"] else: fp = hdulist[""] # to handle older files table = Table.read(fp) if "GTI" in hdulist: gti = GTI.from_table_hdu(hdulist["GTI"]) return cls.from_table( table=table, sed_type=sed_type, reference_model=reference_model, format=format, gti=gti, )
[docs] def write( self, filename, sed_type=None, format=None, overwrite=False, checksum=False ): """Write flux points. Parameters ---------- filename : str Filename. sed_type : {"dnde", "flux", "eflux", "e2dnde", "likelihood"}, optional SED type. Default is None. format : {"gadf-sed", "lightcurve", "binned-time-series", "profile"}, optional Format specification. The following formats are supported: * "gadf-sed": format for SED flux points see :ref:`gadf:flux-points` for details * "lightcurve": Gammapy internal format to store energy dependent lightcurves. Basically a generalisation of the "gadf" format, but currently there is no detailed documentation available. * "binned-time-series": table format support by Astropy's `~astropy.timeseries.BinnedTimeSeries`. * "profile": Gammapy internal format to store energy dependent flux profiles. Basically a generalisation of the "gadf" format, but currently there is no detailed documentation available. If None, the format will be guessed by looking at the axes that are present in the object. Default is None. overwrite : bool, optional Overwrite existing file. Default is False. checksum : bool, optional When True adds both DATASUM and CHECKSUM cards to the headers written to the file. Default is False. """ filename = make_path(filename) if sed_type is None: sed_type = self.sed_type_init table = self.to_table(sed_type=sed_type, format=format) # TODO: rather ugly - better method? if ".fits" not in filename.suffixes: table.write(filename) return primary_hdu = fits.PrimaryHDU() hdu_evt = fits.BinTableHDU(table, name="FLUXPOINTS") hdu_all = fits.HDUList([primary_hdu, hdu_evt]) if self.gti: hdu_all.append(self.gti.to_table_hdu()) hdu_all.writeto(filename, overwrite=overwrite, checksum=checksum)
@staticmethod def _convert_loglike_columns(table): # TODO: check sign and factor 2 here # https://github.com/gammapy/gammapy/pull/2546#issuecomment-554274318 # The idea below is to support the format here: # https://gamma-astro-data-formats.readthedocs.io/en/latest/spectra/flux_points/index.html#likelihood-columns # but internally to go to the uniform "stat" if "loglike" in table.colnames and "stat" not in table.colnames: table["stat"] = 2 * table["loglike"] if "loglike_null" in table.colnames and "stat_null" not in table.colnames: table["stat_null"] = 2 * table["loglike_null"] if "dloglike_scan" in table.colnames and "stat_scan" not in table.colnames: table["stat_scan"] = 2 * table["dloglike_scan"] return table @staticmethod def _table_guess_format(table): """Format of the table to be transformed to FluxPoints.""" names = table.colnames if "time_min" in names: return "lightcurve" elif "x_min" in names: return "profile" else: return "gadf-sed"
[docs] @classmethod def from_table( cls, table, sed_type=None, format=None, reference_model=None, gti=None ): """Create flux points from a table. The table column names must be consistent with the sed_type. Parameters ---------- table : `~astropy.table.Table` Table. sed_type : {"dnde", "flux", "eflux", "e2dnde", "likelihood"}, optional SED type. Default is None. format : {"gadf-sed", "lightcurve", "profile"}, optional Table format. If None, it is extracted from the table column content. Default is None. reference_model : `SpectralModel`, optional Reference spectral model. Default is None. gti : `GTI`, optional Good time intervals. Default is None. Returns ------- flux_points : `FluxPoints` Flux points. """ table = table_standardise_units_copy(table) if format is None: format = cls._table_guess_format(table) log.info("Inferred format: " + format) if sed_type is None: sed_type = table.meta.get("SED_TYPE", None) if sed_type is None: sed_type = cls._guess_sed_type(table.colnames) if sed_type is None: raise ValueError("Specifying the SED type is required") if sed_type == "likelihood": table = cls._convert_loglike_columns(table) if reference_model is None: reference_model = TemplateSpectralModel( energy=flat_if_equal(table["e_ref"].quantity), values=flat_if_equal(table["ref_dnde"].quantity), ) maps = Maps() table.meta.setdefault("SED_TYPE", sed_type) for name in cls.all_quantities(sed_type=sed_type): if name in table.colnames: maps[name] = RegionNDMap.from_table( table=table, colname=name, format=format ) meta = cls._get_meta_gadf(table) return cls.from_maps( maps=maps, reference_model=reference_model, meta=meta, sed_type=sed_type, gti=gti, )
@staticmethod def _get_meta_gadf(table): meta = {} meta.update(table.meta) conf_ul = table.meta.get("UL_CONF") if conf_ul: n_sigma_ul = np.round(stats.norm.isf(0.5 * (1 - conf_ul)), 1) meta["n_sigma_ul"] = n_sigma_ul meta["sed_type_init"] = table.meta.get("SED_TYPE") return meta @staticmethod def _format_table(table): """Format table.""" for column in table.colnames: if column.startswith(("dnde", "eflux", "flux", "e2dnde", "ref")): table[column].format = ".3e" elif column.startswith( ("e_min", "e_max", "e_ref", "sqrt_ts", "norm", "ts", "stat") ): table[column].format = ".3f" return table def _guess_format(self): """Format of the FluxPoints object.""" names = self.geom.axes.names if "time" in names: return "lightcurve" elif "projected-distance" in names: return "profile" else: return "gadf-sed"
[docs] def to_table(self, sed_type=None, format=None, formatted=False): """Create table for a given SED type. Parameters ---------- sed_type : {"likelihood", "dnde", "e2dnde", "flux", "eflux"} SED type to convert to. Default is `likelihood`. format : {"gadf-sed", "lightcurve", "binned-time-series", "profile"}, optional Format specification. The following formats are supported: * "gadf-sed": format for SED flux points see :ref:`gadf:flux-points` for details * "lightcurve": Gammapy internal format to store energy dependent lightcurves. Basically a generalisation of the "gadf" format, but currently there is no detailed documentation available. * "binned-time-series": table format support by Astropy's `~astropy.timeseries.BinnedTimeSeries`. * "profile": Gammapy internal format to store energy dependent flux profiles. Basically a generalisation of the "gadf" format, but currently there is no detailed documentation available. If None, the format will be guessed by looking at the axes that are present in the object. Default is None. formatted : bool Formatted version with column formats applied. Numerical columns are formatted to .3f and .3e respectively. Default is False. Returns ------- table : `~astropy.table.Table` Flux points table. Examples -------- This is how to read and plot example flux points: >>> from gammapy.estimators import FluxPoints >>> fp = FluxPoints.read("$GAMMAPY_DATA/hawc_crab/HAWC19_flux_points.fits") >>> table = fp.to_table(sed_type="flux", formatted=True) >>> print(table[:2]) e_ref e_min e_max flux flux_err flux_ul ts sqrt_ts is_ul TeV TeV TeV 1 / (s cm2) 1 / (s cm2) 1 / (s cm2) ----- ----- ----- ----------- ----------- ----------- -------- ------- ----- 1.334 1.000 1.780 1.423e-11 3.135e-13 nan 2734.000 52.288 False 2.372 1.780 3.160 5.780e-12 1.082e-13 nan 4112.000 64.125 False """ if sed_type is None: sed_type = self.sed_type_init if format is None: format = self._guess_format() log.info("Inferred format: " + format) if format == "gadf-sed": # TODO: what to do with GTI info? if not self.geom.axes.names == ["energy"]: raise ValueError( "Only flux points with a single energy axis " "can be converted to 'gadf-sed'" ) idx = (Ellipsis, 0, 0) table = self.energy_axis.to_table(format="gadf-sed") table.meta["SED_TYPE"] = sed_type if not self.is_convertible_to_flux_sed_type: table.remove_columns(["e_min", "e_max"]) if self.n_sigma_ul: table.meta["UL_CONF"] = np.round( 1 - 2 * stats.norm.sf(self.n_sigma_ul), 7 ) if sed_type == "likelihood": table["ref_dnde"] = self.dnde_ref[idx] table["ref_flux"] = self.flux_ref[idx] table["ref_eflux"] = self.eflux_ref[idx] for quantity in self.all_quantities(sed_type=sed_type): data = getattr(self, quantity, None) if data: table[quantity] = data.quantity[idx] if self.has_stat_profiles: norm_axis = self.stat_scan.geom.axes["norm"] table["norm_scan"] = norm_axis.center.reshape((1, -1)) table["stat"] = self.stat.data[idx] table["stat_scan"] = self.stat_scan.data[idx] table["is_ul"] = self.is_ul.data[idx] if not self.has_ul: table.remove_columns("is_ul") elif format == "lightcurve": time_axis = self.geom.axes["time"] tables = [] for idx, (time_min, time_max) in enumerate(time_axis.iter_by_edges): table_flat = Table() table_flat["time_min"] = [time_min.mjd] table_flat["time_max"] = [time_max.mjd] fp = self.slice_by_idx(slices={"time": idx}) table = fp.to_table(sed_type=sed_type, format="gadf-sed") for column in table.columns: table_flat[column] = table[column][np.newaxis] tables.append(table_flat) table = vstack(tables) # serialize with reference time set to mjd=0.0 ref_time = Time(0.0, format="mjd", scale=time_axis.reference_time.scale) table.meta.update(time_ref_to_dict(ref_time, scale=ref_time.scale)) table.meta["TIMEUNIT"] = "d" elif format == "binned-time-series": message = ( "Format 'binned-time-series' support a single time axis " f"only. Got {self.geom.axes.names}" ) if not self.geom.axes.is_unidimensional: raise ValueError(message) axis = self.geom.axes.primary_axis if not isinstance(axis, TimeMapAxis): raise ValueError(message) table = Table() table["time_bin_start"] = axis.time_min table["time_bin_size"] = axis.time_delta for quantity in self.all_quantities(sed_type=sed_type): data = getattr(self, quantity, None) if data: table[quantity] = data.quantity.squeeze() elif format == "profile": x_axis = self.geom.axes["projected-distance"] tables = [] for idx, (x_min, x_max) in enumerate(x_axis.iter_by_edges): table_flat = Table() table_flat["x_min"] = [x_min] table_flat["x_max"] = [x_max] table_flat["x_ref"] = [(x_max + x_min) / 2] fp = self.slice_by_idx(slices={"projected-distance": idx}) table = fp.to_table(sed_type=sed_type, format="gadf-sed") for column in table.columns: table_flat[column] = table[column][np.newaxis] tables.append(table_flat) table = vstack(tables) else: raise ValueError(f"Not a supported format {format}") if formatted: table = self._format_table(table=table) return table
@staticmethod def _energy_ref_lafferty(model, energy_min, energy_max): """Helper for `to_sed_type`. Compute energy_ref that the value at energy_ref corresponds to the mean value between energy_min and energy_max. """ flux = model.integral(energy_min, energy_max) dnde_mean = flux / (energy_max - energy_min) return model.inverse(dnde_mean) def _plot_get_flux_err(self, sed_type=None): """Compute flux error for given SED type""" y_errn, y_errp = None, None if "norm_err" in self.available_quantities: # symmetric error y_errn = getattr(self, sed_type + "_err") y_errp = y_errn.copy() if "norm_errp" in self.available_quantities: y_errn = getattr(self, sed_type + "_errn") y_errp = getattr(self, sed_type + "_errp") return y_errn, y_errp
[docs] def plot(self, ax=None, sed_type=None, energy_power=0, time_format="iso", **kwargs): """Plot flux points. Parameters ---------- ax : `~matplotlib.axes.Axes`, optional Axis object to plot on. Default is None. sed_type : {"dnde", "flux", "eflux", "e2dnde"}, optional SED type. Default is None. energy_power : float, optional Power of energy to multiply flux axis with. Default is 0. time_format : {"iso", "mjd"} Used time format is a time axis is present. Default is "iso". **kwargs : dict, optional Keyword arguments passed to `~RegionNDMap.plot`. Returns ------- ax : `~matplotlib.axes.Axes` Axis object. """ if sed_type is None: sed_type = self.sed_type_plot_default if not self.norm.geom.is_region: raise ValueError("Plotting only supported for region based flux points") if ax is None: ax = plt.gca() flux_unit = DEFAULT_UNIT[sed_type] flux = getattr(self, sed_type) # get errors and ul y_errn, y_errp = self._plot_get_flux_err(sed_type=sed_type) is_ul = self.is_ul.data if self.has_ul and y_errn and is_ul.any(): flux_ul = getattr(self, sed_type + "_ul").quantity y_errn.data[is_ul] = np.clip( 0.5 * flux_ul[is_ul].to_value(y_errn.unit), 0, np.inf ) y_errp.data[is_ul] = 0 flux.data[is_ul] = flux_ul[is_ul].to_value(flux.unit) kwargs.setdefault("uplims", is_ul) # set flux points plotting defaults if y_errp and y_errn: y_errp = np.clip( scale_plot_flux(y_errp, energy_power=energy_power).quantity, 0, np.inf ) y_errn = np.clip( scale_plot_flux(y_errn, energy_power=energy_power).quantity, 0, np.inf ) kwargs.setdefault("yerr", (y_errn, y_errp)) else: kwargs.setdefault("yerr", None) flux = scale_plot_flux(flux=flux.to_unit(flux_unit), energy_power=energy_power) if "time" in flux.geom.axes_names: flux.geom.axes["time"].time_format = time_format ax = flux.plot(ax=ax, **kwargs) ax.set_ylabel(f"{sed_type} [{ax.yaxis.units.to_string(UNIT_STRING_FORMAT)}]") ax.set_yscale("log") return ax
[docs] def plot_ts_profiles( self, ax=None, sed_type=None, add_cbar=True, **kwargs, ): """Plot fit statistic SED profiles as a density plot. Parameters ---------- ax : `~matplotlib.axes.Axes`, optional Axis object to plot on. Default is None. sed_type : {"dnde", "flux", "eflux", "e2dnde"}, optional SED type. Default is None. add_cbar : bool, optional Whether to add a colorbar to the plot. Default is True. **kwargs : dict, optional Keyword arguments passed to `~matplotlib.pyplot.pcolormesh`. Returns ------- ax : `~matplotlib.axes.Axes` Axis object. """ if ax is None: ax = plt.gca() if sed_type is None: sed_type = self.sed_type_plot_default if not self.norm.geom.is_region: raise ValueError("Plotting only supported for region based flux points") if not self.geom.axes.is_unidimensional: raise ValueError( "Profile plotting is only supported for unidimensional maps" ) axis = self.geom.axes.primary_axis if isinstance(axis, TimeMapAxis) and not axis.is_contiguous: axis = axis.to_contiguous() if ax.yaxis.units is None: yunits = DEFAULT_UNIT[sed_type] else: yunits = ax.yaxis.units ax.yaxis.set_units(yunits) flux_ref = getattr(self, sed_type + "_ref").to(yunits) ts = self.ts_scan norm_min, norm_max = ts.geom.axes["norm"].bounds.to_value("") flux = MapAxis.from_bounds( norm_min * flux_ref.value.min(), norm_max * flux_ref.value.max(), nbin=500, interp=axis.interp, unit=flux_ref.unit, ) norm = flux.center / flux_ref.reshape((-1, 1)) coords = ts.geom.get_coord() coords["norm"] = norm coords[axis.name] = axis.center.reshape((-1, 1)) z = ts.interp_by_coord(coords, values_scale="stat-profile") kwargs.setdefault("vmax", 0) kwargs.setdefault("vmin", -4) kwargs.setdefault("zorder", 0) kwargs.setdefault("cmap", "Blues") kwargs.setdefault("linewidths", 0) kwargs.setdefault("shading", "auto") # clipped values are set to NaN so that they appear white on the plot z[-z < kwargs["vmin"]] = np.nan with quantity_support(): caxes = ax.pcolormesh(axis.as_plot_edges, flux.edges, -z.T, **kwargs) axis.format_plot_xaxis(ax=ax) ax.set_ylabel(f"{sed_type} [{ax.yaxis.units.to_string(UNIT_STRING_FORMAT)}]") ax.set_yscale("log") if add_cbar: label = "Fit statistic difference" ax.figure.colorbar(caxes, ax=ax, label=label) return ax
[docs] def recompute_ul(self, n_sigma_ul=2, **kwargs): """Recompute upper limits corresponding to the given value. The pre-computed statistic profiles must exist for the re-computation. Parameters ---------- n_sigma_ul : int Number of sigma to use for upper limit computation. Default is 2. **kwargs : dict, optional Keyword arguments passed to `~scipy.optimize.brentq`. Returns ------- flux_points : `~gammapy.estimators.FluxPoints` A new FluxPoints object with modified upper limits. Examples -------- >>> from gammapy.estimators import FluxPoints >>> filename = '$GAMMAPY_DATA/tests/spectrum/flux_points/binlike.fits' >>> flux_points = FluxPoints.read(filename) >>> flux_points_recomputed = flux_points.recompute_ul(n_sigma_ul=3) >>> print(flux_points.meta["n_sigma_ul"], flux_points.flux_ul.data[0]) 2.0 [[3.95451985e-09]] >>> print(flux_points_recomputed.meta["n_sigma_ul"], flux_points_recomputed.flux_ul.data[0]) 3 [[6.22245374e-09]] """ if not self.has_stat_profiles: raise ValueError( "Stat profiles not present. Upper limit computation is not possible" ) delta_ts = n_sigma_ul**2 flux_points = deepcopy(self) value_scan = self.stat_scan.geom.axes["norm"].center shape_axes = self.stat_scan.geom._shape[slice(3, None)] for idx in np.ndindex(shape_axes): stat_scan = np.abs( self.stat_scan.data[idx].squeeze() - self.stat.data[idx].squeeze() ) flux_points.norm_ul.data[idx] = stat_profile_ul_scipy( value_scan, stat_scan, delta_ts=delta_ts, **kwargs ) flux_points.meta["n_sigma_ul"] = n_sigma_ul return flux_points
[docs] def resample_axis(self, axis_new): """Rebin the flux point object along the new axis. The log-likelihoods profiles in each bin are summed to compute the resultant quantities. Stat profiles must be present on the fluxpoints object for this method to work. For now, works only for flat fluxpoints. Parameters ---------- axis_new : `MapAxis` or `TimeMapAxis` The new axis to resample along Returns ------- flux_points : `~gammapy.estimators.FluxPoints` A new FluxPoints object with modified axis. """ if not self.has_stat_profiles: raise ValueError("Stat profiles not present, rebinning is not possible") fluxpoints = [] for edge_min, edge_max in zip(axis_new.edges_min, axis_new.edges_max): if isinstance(axis_new, TimeMapAxis): edge_min = edge_min + axis_new.reference_time edge_max = edge_max + axis_new.reference_time fp = self.slice_by_coord({axis_new.name: slice(edge_min, edge_max)}) fp_new = squash_fluxpoints(fp, axis_new) fluxpoints.append(fp_new) return self.__class__.from_stack(fluxpoints, axis=axis_new)