SpectrumDataset#

class gammapy.datasets.SpectrumDataset(models=None, counts=None, exposure=None, background=None, psf=None, edisp=None, mask_safe=None, mask_fit=None, gti=None, meta_table=None, name=None, meta=None)[source]#

Bases: PlotMixin, MapDataset

Main dataset for spectrum fitting (1D analysis). It bundles together binned counts, background, IRFs into RegionNDMap (a Map with only one spatial bin). A safe mask and a fit mask can be added to exclude bins during the analysis. If models are assigned to it, it can compute the predicted number of counts and the statistic function, here the Cash statistic (see cash).

For more information see Datasets (DL4).

Attributes Summary

`background`	A lazy FITS data descriptor.
`background_model`
`counts`	A lazy FITS data descriptor.
`data_shape`	Shape of the counts or background data (tuple).
`edisp`	A lazy FITS data descriptor.
`energy_range`	Energy range maps defined by the mask_safe and mask_fit.
`energy_range_fit`	Energy range maps defined by the mask_fit only.
`energy_range_safe`	Energy range maps defined by the mask_safe only.
`energy_range_total`	Largest energy range among all pixels, defined by mask_safe and mask_fit.
`evaluators`	Model evaluators.
`excess`	Observed excess: counts-background.
`exposure`	A lazy FITS data descriptor.
`geoms`	Map geometries.
`gti`
`mask`	Combined fit and safe mask.
`mask_fit`	A lazy FITS data descriptor.
`mask_fit_image`	Reduced fit mask.
`mask_image`	Reduced mask.
`mask_safe`	A lazy FITS data descriptor.
`mask_safe_edisp`	Safe mask for edisp maps.
`mask_safe_image`	Reduced safe mask.
`mask_safe_psf`	Safe mask for PSF maps.
`meta`
`meta_table`
`models`	Models set on the dataset (`Models`).
`name`
`psf`	A lazy FITS data descriptor.
`stat_type`
`tag`

Methods Summary

`copy`([name])	A deep copy.
`create`(geom[, energy_axis_true, migra_axis, ...])	Create a MapDataset object with zero filled maps.
`cutout`(args, *kwargs)	Not supported for `SpectrumDataset`
`downsample`(factor[, axis_name, name])	Downsample map dataset.
`fake`([random_state])	Simulate fake counts for the current model and reduced IRFs.
`from_dict`(data[, lazy, cache])	Create from dicts and models list generated from YAML serialization.
`from_geoms`(geom[, geom_exposure, geom_psf, ...])	Create a MapDataset object with zero filled maps according to the specified geometries.
`from_hdulist`(hdulist[, name, lazy, format])	Create map dataset from list of HDUs.
`info_dict`([in_safe_data_range])	Info dict with summary statistics, summed over energy.
`npred`()	Total predicted source and background counts.
`npred_background`()	Predicted background counts.
`npred_signal`([model_names, stack])	Model predicted signal counts.
`pad`(pad_width[, mode, name])	Pad the spatial dimensions of the dataset.
`peek`([figsize])	Quick-look summary plots.
`plot_counts`([ax, kwargs_counts, ...])	Plot counts and background.
`plot_excess`([ax, kwargs_excess, ...])	Plot excess and predicted signal.
`plot_fit`([ax_spectrum, ax_residuals, ...])	Plot spectrum and residuals in two panels.
`plot_masks`([ax, kwargs_fit, kwargs_safe])	Plot safe mask and fit mask.
`plot_residuals`([ax_spatial, ax_spectral, ...])	Plot spatial and spectral residuals in two panels.
`plot_residuals_spatial`(args, *kwargs)	Not supported for `SpectrumDataset`
`plot_residuals_spectral`([ax, method, region])	Plot spectral residuals.
`read`(filename[, name, lazy, cache, format, ...])	Read a dataset from file.
`resample_energy_axis`(energy_axis[, name])	Resample MapDataset over new reco energy axis.
`reset_data_cache`()	Reset data cache to free memory space.
`residuals`([method])	Compute residuals map.
`slice_by_energy`([energy_min, energy_max, name])	Select and slice datasets in energy range.
`slice_by_idx`(slices[, name])	Slice sub dataset.
`stack`(other[, nan_to_num])	Stack another dataset in place.
`stat_array`()	Statistic function value per bin given the current model parameters.
`stat_sum`()	Total statistic function value given the current model parameters and priors.
`to_dict`()	Convert to dict for YAML serialization.
`to_hdulist`()	Convert map dataset to list of HDUs.
`to_image`([name])	Create images by summing over the reconstructed energy axis.
`to_masked`([name, nan_to_num])	Return masked dataset.
`to_region_map_dataset`(region[, name])	Integrate the map dataset in a given region.
`to_spectrum_dataset`(args, *kwargs)	Not supported for `SpectrumDataset`
`write`(filename[, overwrite, checksum])	Write Dataset to file.

Attributes Documentation

background#

A lazy FITS data descriptor.

Parameters:

cachebool: Whether to cache the data.

background_model#

counts#

A lazy FITS data descriptor.

Parameters:

cachebool: Whether to cache the data.

data_shape#: Shape of the counts or background data (tuple).

edisp#

A lazy FITS data descriptor.

Parameters:

cachebool: Whether to cache the data.

energy_range#: Energy range maps defined by the mask_safe and mask_fit.

energy_range_fit#: Energy range maps defined by the mask_fit only.

energy_range_safe#: Energy range maps defined by the mask_safe only.

energy_range_total#: Largest energy range among all pixels, defined by mask_safe and mask_fit.

evaluators#: Model evaluators.

excess#: Observed excess: counts-background.

exposure#

A lazy FITS data descriptor.

Parameters:

cachebool: Whether to cache the data.

geoms#

Map geometries.

Returns:

geomsdict: Dictionary of map geometries involved in the dataset.

gti = None#

mask#: Combined fit and safe mask.

mask_fit#

A lazy FITS data descriptor.

Parameters:

cachebool: Whether to cache the data.

mask_fit_image#: Reduced fit mask.

mask_image#: Reduced mask.

mask_safe#

A lazy FITS data descriptor.

Parameters:

cachebool: Whether to cache the data.

mask_safe_edisp#: Safe mask for edisp maps.

mask_safe_image#: Reduced safe mask.

mask_safe_psf#: Safe mask for PSF maps.

meta#

meta_table = None#

models#: Models set on the dataset (Models).

name#

psf#

A lazy FITS data descriptor.

Parameters:

cachebool: Whether to cache the data.

stat_type = 'cash'#

tag = 'SpectrumDataset'#

Methods Documentation

copy(name=None)#

A deep copy.

Parameters:

namestr, optional: Name of the copied dataset. Default is None.

Returns:

datasetDataset: Copied datasets.

classmethod create(geom, energy_axis_true=None, migra_axis=None, rad_axis=None, binsz_irf=<Quantity 0.2 deg>, reference_time='2000-01-01', name=None, meta_table=None, reco_psf=False, **kwargs)#

Create a MapDataset object with zero filled maps.

Parameters:

geomWcsGeom: Reference target geometry in reco energy, used for counts and background maps.
energy_axis_trueMapAxis, optional: True energy axis used for IRF maps. Default is None.
migra_axisMapAxis, optional: If set, this provides the migration axis for the energy dispersion map. If not set, an EDispKernelMap is produced instead. Default is None.
rad_axisMapAxis, optional: Rad axis for the PSF map. Default is None.
binsz_irffloat: IRF Map pixel size in degrees. Default is BINSZ_IRF_DEFAULT.
reference_timeTime: The reference time to use in GTI definition. Default is “2000-01-01”.
namestr, optional: Name of the returned dataset. Default is None.
meta_tableTable, optional: Table listing information on observations used to create the dataset. One line per observation for stacked datasets. Default is None.
reco_psfbool: Use reconstructed energy for the PSF geometry. Default is False.

Returns:

empty_mapsMapDataset: A MapDataset containing zero filled maps.

Examples

>>> from gammapy.datasets import MapDataset
>>> from gammapy.maps import WcsGeom, MapAxis

>>> energy_axis = MapAxis.from_energy_bounds(1.0, 10.0, 4, unit="TeV")
>>> energy_axis_true = MapAxis.from_energy_bounds(
...            0.5, 20, 10, unit="TeV", name="energy_true"
...        )
>>> geom = WcsGeom.create(
...            skydir=(83.633, 22.014),
...            binsz=0.02, width=(2, 2),
...            frame="icrs",
...            proj="CAR",
...            axes=[energy_axis]
...        )
>>> empty = MapDataset.create(geom=geom, energy_axis_true=energy_axis_true, name="empty")

cutout(*args, **kwargs)[source]#: Not supported for SpectrumDataset

downsample(factor, axis_name=None, name=None)#

Downsample map dataset.

The PSFMap and EDispKernelMap are not downsampled, except if a corresponding axis is given.

Parameters:

factorint: Downsampling factor.
axis_namestr, optional: Which non-spatial axis to downsample. By default only spatial axes are downsampled. Default is None.
namestr, optional: Name of the downsampled dataset. Default is None.

Returns:

datasetMapDataset or SpectrumDataset: Downsampled map dataset.

fake(random_state='random-seed')#

Simulate fake counts for the current model and reduced IRFs.

This method overwrites the counts defined on the dataset object.

Parameters:

random_state{int, ‘random-seed’, ‘global-rng’, RandomState}: Defines random number generator initialisation. Passed to get_random_state. Default is “random-seed”.

classmethod from_dict(data, lazy=False, cache=True)#: Create from dicts and models list generated from YAML serialization.

classmethod from_geoms(geom, geom_exposure=None, geom_psf=None, geom_edisp=None, reference_time='2000-01-01', name=None, **kwargs)#

Create a MapDataset object with zero filled maps according to the specified geometries.

Parameters:

geomGeom: Geometry for the counts and background maps.
geom_exposureGeom: Geometry for the exposure map. Default is None.
geom_psfGeom: Geometry for the PSF map. Default is None.
geom_edispGeom: Geometry for the energy dispersion kernel map. If geom_edisp has a migra axis, this will create an EDispMap instead. Default is None.
reference_timeTime: The reference time to use in GTI definition. Default is “2000-01-01”.
namestr: Name of the returned dataset. Default is None.
kwargsdict, optional: Keyword arguments to be passed.

Returns:

datasetMapDataset or SpectrumDataset: A dataset containing zero filled maps.

classmethod from_hdulist(hdulist, name=None, lazy=False, format='gadf')#

Create map dataset from list of HDUs.

Parameters:

hdulistHDUList: List of HDUs.
namestr, optional: Name of the new dataset. Default is None.
lazybool: Whether to lazy load data into memory. Default is False.
format{“gadf”}: Format the hdulist is given in. Default is “gadf”.

Returns:

datasetMapDataset: Map dataset.

info_dict(in_safe_data_range=True)#

Info dict with summary statistics, summed over energy.

Parameters:

in_safe_data_rangebool: Whether to sum only in the safe energy range. Default is True.

Returns:

info_dictdict: Dictionary with summary info.

npred()#

Total predicted source and background counts.

Returns:

npredMap: Total predicted counts.

npred_background()#

Predicted background counts.

The predicted background counts depend on the parameters of the FoVBackgroundModel defined in the dataset.

Returns:

npred_backgroundMap: Predicted counts from the background.

npred_signal(model_names=None, stack=True)#

Model predicted signal counts.

If a list of model name is passed, predicted counts from these components are returned. If stack is set to True, a map of the sum of all the predicted counts is returned. If stack is set to False, a map with an additional axis representing the models is returned.

Parameters:

model_nameslist of str: List of name of SkyModel for which to compute the npred. If none, all the SkyModel predicted counts are computed.
stackbool: Whether to stack the npred maps upon each other.

Returns:

npred_siggammapy.maps.Map: Map of the predicted signal counts.

pad(pad_width, mode='constant', name=None)#

Pad the spatial dimensions of the dataset.

The padding only applies to counts, masks, background and exposure.

Counts, background and masks are padded with zeros, exposure is padded with edge value.

Parameters:

pad_width{sequence, array_like, int}: Number of pixels padded to the edges of each axis.
modestr: Pad mode. Default is “constant”.
namestr, optional: Name of the padded dataset. Default is None.

Returns:

datasetMapDataset: Padded map dataset.

peek(figsize=(16, 4))#

Quick-look summary plots.

Parameters:

figsizetuple: Size of the figure. Default is (16, 4).

plot_counts(ax=None, kwargs_counts=None, kwargs_background=None, **kwargs)#

Plot counts and background.

Parameters:

axAxes, optional: Axes to plot on. Default is None.
kwargs_countsdict, optional: Keyword arguments passed to hist for the counts. Default is None.
kwargs_backgrounddict, optional: Keyword arguments passed to hist for the background. Default is None.
**kwargsdict, optional: Keyword arguments passed to both hist.

Returns:

axAxes: Axes object.

plot_excess(ax=None, kwargs_excess=None, kwargs_npred_signal=None, **kwargs)#

Plot excess and predicted signal.

The error bars are computed with a symmetric assumption on the excess.

Parameters:

axAxes, optional: Axes to plot on. Default is None.
kwargs_excessdict, optional: Keyword arguments passed to errorbar for the excess. Default is None.
kwargs_npred_signaldict, optional: Keyword arguments passed to hist for the predicted signal. Default is None.
**kwargsdict, optional: Keyword arguments passed to both plot methods.

Returns:

axAxes: Axes object.

Examples

>>> #Creating a spectral dataset
>>> from gammapy.datasets import SpectrumDatasetOnOff
>>> from gammapy.modeling.models import PowerLawSpectralModel, SkyModel
>>> filename = "$GAMMAPY_DATA/joint-crab/spectra/hess/pha_obs23523.fits"
>>> dataset = SpectrumDatasetOnOff.read(filename)
>>> p = PowerLawSpectralModel()
>>> dataset.models = SkyModel(spectral_model=p)
>>> #Plot the excess in blue and the npred in black dotted lines
>>> kwargs_excess = {"color": "blue", "markersize":8, "marker":'s', }
>>> kwargs_npred_signal = {"color": "black", "ls":"--"}
>>> dataset.plot_excess(kwargs_excess=kwargs_excess, kwargs_npred_signal=kwargs_npred_signal)  

plot_fit(ax_spectrum=None, ax_residuals=None, kwargs_spectrum=None, kwargs_residuals=None)#

Plot spectrum and residuals in two panels.

Calls plot_excess and plot_residuals_spectral.

Parameters:

ax_spectrumAxes, optional: Axes to plot spectrum on. Default is None.
ax_residualsAxes, optional: Axes to plot residuals on. Default is None.
kwargs_spectrumdict, optional: Keyword arguments passed to plot_excess. Default is None.
kwargs_residualsdict, optional: Keyword arguments passed to plot_residuals_spectral. Default is None.

Returns:

ax_spectrum, ax_residualsAxes: Spectrum and residuals plots.

Examples

>>> #Creating a spectral dataset
>>> from gammapy.datasets import SpectrumDatasetOnOff
>>> from gammapy.modeling.models import PowerLawSpectralModel, SkyModel
>>> filename = "$GAMMAPY_DATA/joint-crab/spectra/hess/pha_obs23523.fits"
>>> dataset = SpectrumDatasetOnOff.read(filename)
>>> p = PowerLawSpectralModel()
>>> dataset.models = SkyModel(spectral_model=p)
>>> # optional configurations
>>> kwargs_excess = {"color": "blue", "markersize":8, "marker":'s', }
>>> kwargs_npred_signal = {"color": "black", "ls":"--"}
>>> kwargs_spectrum = {"kwargs_excess":kwargs_excess, "kwargs_npred_signal":kwargs_npred_signal}
>>> kwargs_residuals = {"color": "black", "markersize":4, "marker":'s', }
>>> dataset.plot_fit(kwargs_residuals=kwargs_residuals, kwargs_spectrum=kwargs_spectrum)  

plot_masks(ax=None, kwargs_fit=None, kwargs_safe=None)#

Plot safe mask and fit mask.

Parameters:

axAxes, optional: Axes to plot on. Default is None.
kwargs_fitdict, optional: Keyword arguments passed to plot_mask() for mask fit. Default is None.
kwargs_safedict, optional: Keyword arguments passed to plot_mask() for mask safe. Default is None.

Returns:

axAxes: Axes object.

Examples

>>> # Reading a spectral dataset
>>> from gammapy.datasets import SpectrumDatasetOnOff
>>> filename = "$GAMMAPY_DATA/joint-crab/spectra/hess/pha_obs23523.fits"
>>> dataset = SpectrumDatasetOnOff.read(filename)
>>> dataset.mask_fit = dataset.mask_safe.copy()
>>> dataset.mask_fit.data[40:46] = False  # setting dummy mask_fit for illustration
>>> # Plot the masks on top of the counts histogram
>>> kwargs_safe = {"color":"green", "alpha":0.2} #optinonal arguments to configure
>>> kwargs_fit = {"color":"pink", "alpha":0.2}
>>> ax=dataset.plot_counts()  
>>> dataset.plot_masks(ax=ax, kwargs_fit=kwargs_fit, kwargs_safe=kwargs_safe)  

plot_residuals(ax_spatial=None, ax_spectral=None, kwargs_spatial=None, kwargs_spectral=None)#

Plot spatial and spectral residuals in two panels.

Calls plot_residuals_spatial and plot_residuals_spectral. The spectral residuals are extracted from the provided region, and the normalization used for its computation can be controlled using the method parameter. The region outline is overlaid on the residuals map. If no region is passed, the residuals are computed for the entire map.

Parameters:

ax_spatialWCSAxes, optional: Axes to plot spatial residuals on. Default is None.
ax_spectralAxes, optional: Axes to plot spectral residuals on. Default is None.
kwargs_spatialdict, optional: Keyword arguments passed to plot_residuals_spatial. Default is None.
kwargs_spectraldict, optional: Keyword arguments passed to plot_residuals_spectral. The region should be passed as a dictionary key. Default is None.

Returns:

ax_spatial, ax_spectralWCSAxes, Axes: Spatial and spectral residuals plots.

Examples

>>> from regions import CircleSkyRegion
>>> from astropy.coordinates import SkyCoord
>>> import astropy.units as u
>>> from gammapy.datasets import MapDataset
>>> dataset = MapDataset.read("$GAMMAPY_DATA/cta-1dc-gc/cta-1dc-gc.fits.gz")
>>> reg = CircleSkyRegion(SkyCoord(0,0, unit="deg", frame="galactic"), radius=1.0 * u.deg)
>>> kwargs_spatial = {"cmap": "RdBu_r", "vmin":-5, "vmax":5, "add_cbar": True}
>>> kwargs_spectral = {"region":reg, "markerfacecolor": "blue", "markersize": 8, "marker": "s"}
>>> dataset.plot_residuals(kwargs_spatial=kwargs_spatial, kwargs_spectral=kwargs_spectral) 

plot_residuals_spatial(*args, **kwargs)[source]#: Not supported for SpectrumDataset

plot_residuals_spectral(ax=None, method='diff', region=None, **kwargs)#

Plot spectral residuals.

The residuals are extracted from the provided region, and the normalization used for its computation can be controlled using the method parameter.

The error bars are computed using the uncertainty on the excess with a symmetric assumption.

Parameters:

axAxes, optional: Axes to plot on. Default is None.
method{“diff”, “diff/sqrt(model)”}: Normalization used to compute the residuals, see SpectrumDataset.residuals. Default is “diff”.
regionSkyRegion (required): Target sky region. Default is None.
**kwargsdict, optional: Keyword arguments passed to errorbar.

Returns:

axAxes: Axes object.

Examples

>>> from gammapy.datasets import MapDataset
>>> dataset = MapDataset.read("$GAMMAPY_DATA/cta-1dc-gc/cta-1dc-gc.fits.gz")
>>> kwargs = {"markerfacecolor": "blue", "markersize":8, "marker":'s'}
>>> dataset.plot_residuals_spectral(method="diff/sqrt(model)", **kwargs) 

classmethod read(filename, name=None, lazy=False, cache=True, format='gadf', checksum=False)#

Read a dataset from file.

Parameters:

filenamestr: Filename to read from.
namestr, optional: Name of the new dataset. Default is None.
lazybool: Whether to lazy load data into memory. Default is False.
cachebool: Whether to cache the data after loading. Default is True.
format{“gadf”}: Format of the dataset file. Default is “gadf”.
checksumbool: If True checks both DATASUM and CHECKSUM cards in the file headers. Default is False.

Returns:

datasetMapDataset: Map dataset.

resample_energy_axis(energy_axis, name=None)#

Resample MapDataset over new reco energy axis.

Counts are summed taking into account safe mask.

Parameters:

energy_axisMapAxis: New reconstructed energy axis.
namestr, optional: Name of the new dataset. Default is None.

Returns:

datasetMapDataset or SpectrumDataset: Resampled dataset.

reset_data_cache()#: Reset data cache to free memory space.

residuals(method='diff', **kwargs)#

Compute residuals map.

Parameters:

method{“diff”, “diff/model”, “diff/sqrt(model)”}

Method used to compute the residuals. Available options are:

“diff” (default): data - model.
“diff/model”: (data - model) / model.
“diff/sqrt(model)”: (data - model) / sqrt(model).

Default is “diff”.

**kwargsdict, optional

Keyword arguments forwarded to Map.smooth().

Returns:

residualsgammapy.maps.Map: Residual map.

slice_by_energy(energy_min=None, energy_max=None, name=None)#

Select and slice datasets in energy range.

Parameters:

energy_min, energy_maxQuantity, optional: Energy bounds to compute the flux point for. Default is None.
namestr, optional: Name of the sliced dataset. Default is None.

Returns:

datasetMapDataset: Sliced Dataset.

Examples

>>> from gammapy.datasets import MapDataset
>>> dataset = MapDataset.read("$GAMMAPY_DATA/cta-1dc-gc/cta-1dc-gc.fits.gz")
>>> sliced = dataset.slice_by_energy(energy_min="1 TeV", energy_max="5 TeV")
>>> sliced.data_shape
(3, np.int64(240), np.int64(320))

slice_by_idx(slices, name=None)#

Slice sub dataset.

The slicing only applies to the maps that define the corresponding axes.

Parameters:

slicesdict: Dictionary of axes names and integers or slice object pairs. Contains one element for each non-spatial dimension. For integer indexing the corresponding axes is dropped from the map. Axes not specified in the dict are kept unchanged.
namestr, optional: Name of the sliced dataset. Default is None.

Returns:

datasetMapDataset or SpectrumDataset: Sliced dataset.

Examples

>>> from gammapy.datasets import MapDataset
>>> dataset = MapDataset.read("$GAMMAPY_DATA/cta-1dc-gc/cta-1dc-gc.fits.gz")
>>> slices = {"energy": slice(0, 3)} #to get the first 3 energy slices
>>> sliced = dataset.slice_by_idx(slices)
>>> print(sliced.geoms["geom"])
WcsGeom

    axes       : ['lon', 'lat', 'energy']
    shape      : (np.int64(320), np.int64(240), 3)
    ndim       : 3
    frame      : galactic
    projection : CAR
    center     : 0.0 deg, 0.0 deg
    width      : 8.0 deg x 6.0 deg
    wcs ref    : 0.0 deg, 0.0 deg

stack(other, nan_to_num=True)#

Stack another dataset in place. The original dataset is modified.

Safe mask is applied to the other dataset to compute the stacked counts data. Counts outside the safe mask are lost.

Note that the masking is not applied to the current dataset. If masking needs to be applied to it, use to_masked() first.

The stacking of 2 datasets is implemented as follows. Here, \(k\) denotes a bin in reconstructed energy and \(j = {1,2}\) is the dataset number.

The mask_safe of each dataset is defined as:

\[\begin{split}\epsilon_{jk} =\left\{\begin{array}{cl} 1, & \mbox{if bin k is inside the thresholds}\\ 0, & \mbox{otherwise} \end{array}\right.\end{split}\]

Then the total counts and model background bkg are computed according to:

\[ \begin{align}\begin{aligned}\overline{\mathrm{n_{on}}}_k = \mathrm{n_{on}}_{1k} \cdot \epsilon_{1k} + \mathrm{n_{on}}_{2k} \cdot \epsilon_{2k}.\\\overline{bkg}_k = bkg_{1k} \cdot \epsilon_{1k} + bkg_{2k} \cdot \epsilon_{2k}.\end{aligned}\end{align} \]

The stacked safe_mask is then:

\[\overline{\epsilon_k} = \epsilon_{1k} OR \epsilon_{2k}.\]

For details, see Stacking Multiple Datasets.

Parameters:

otherMapDataset or MapDatasetOnOff: Map dataset to be stacked with this one. If other is an on-off dataset alpha * counts_off is used as a background model.
nan_to_numbool: Non-finite values are replaced by zero if True. Default is True.

stat_array()#: Statistic function value per bin given the current model parameters.

stat_sum()#: Total statistic function value given the current model parameters and priors.

to_dict()#: Convert to dict for YAML serialization.

to_hdulist()#

Convert map dataset to list of HDUs.

Returns:

hdulistHDUList: Map dataset list of HDUs.

to_image(name=None)#

Create images by summing over the reconstructed energy axis.

Parameters:

namestr, optional: Name of the new dataset. Default is None.

Returns:

datasetMapDataset or SpectrumDataset: Dataset integrated over non-spatial axes.

to_masked(name=None, nan_to_num=True)#

Return masked dataset.

Parameters:

namestr, optional: Name of the masked dataset. Default is None.
nan_to_numbool: Non-finite values are replaced by zero if True. Default is True.

Returns:

datasetMapDataset or SpectrumDataset: Masked dataset.

to_region_map_dataset(region, name=None)#

Integrate the map dataset in a given region.

Counts and background of the dataset are integrated in the given region, taking the safe mask into account. The exposure is averaged in the region again taking the safe mask into account. The PSF and energy dispersion kernel are taken at the center of the region.

Parameters:

regionSkyRegion: Region from which to extract the spectrum.
namestr, optional: Name of the new dataset. Default is None.

Returns:

datasetMapDataset: The resulting reduced dataset.

to_spectrum_dataset(*args, **kwargs)[source]#: Not supported for SpectrumDataset

write(filename, overwrite=False, checksum=False)#

Write Dataset to file.

A MapDataset is serialised using the GADF format with a WCS geometry. A SpectrumDataset uses the same format, with a RegionGeom.

Parameters:

filenamestr: Filename to write to.
overwritebool, optional: Overwrite existing file. Default is False.
checksumbool: When True adds both DATASUM and CHECKSUM cards to the headers written to the file. Default is False.