EDispKernelMap#

class gammapy.irf.EDispKernelMap(edisp_kernel_map, exposure_map=None)[source]#

Bases: IRFMap

Energy dispersion kernel map.

Parameters:

edisp_kernel_mapMap: The input energy dispersion kernel map. Should be a Map with 2 non-spatial axes. Reconstructed and true energy axes should be given in this specific order.
exposure_mapMap, optional: Associated exposure map. Needs to have a consistent map geometry.

Attributes Summary

`edisp_map`
`mask_safe_image`	Mask safe for the map.
`required_axes`
`tag`

Methods Summary

`copy`()	Copy IRF map.
`cutout`(position, width[, mode])	Cutout IRF map.
`downsample`(factor[, axis_name, weights])	Downsample the spatial dimension by a given factor.
`from_diagonal_response`(energy_axis, ...[, geom])	Create an energy dispersion map with diagonal response.
`from_edisp_kernel`(edisp[, geom])	Create an energy dispersion map from the input 1D kernel.
`from_gauss`(energy_axis, energy_axis_true, ...)	Create an energy dispersion map from the input 1D kernel.
`from_geom`(geom)	Create energy dispersion map from geometry.
`from_hdulist`(hdulist[, hdu, hdu_bands, ...])	Create from `HDUList`.
`get_edisp_kernel`([position, energy_axis])	Get energy dispersion at a given position.
`peek`([figsize])	Quick-look summary plots.
`read`(filename[, format, hdu, checksum])	Read an IRF_map from file and create corresponding object.
`resample_energy_axis`(energy_axis[, weights])	Return a resampled `EDispKernelMap`.
`slice_by_idx`(slices)	Slice sub dataset.
`stack`(other[, weights, nan_to_num])	Stack IRF map with another one in place.
`to_hdulist`([format])	Convert to `HDUList`.
`to_image`([weights])	Return a 2D EdispKernelMap by summing over the reconstructed energy axis.
`to_region_nd_map`(region)	Extract IRFMap in a given region or position.
`write`(filename[, overwrite, format, checksum])	Write IRF map to fits.

Attributes Documentation

edisp_map#

mask_safe_image#: Mask safe for the map.

required_axes = ['energy', 'energy_true']#

tag = 'edisp_kernel_map'#

Methods Documentation

copy()#: Copy IRF map.

cutout(position, width, mode='trim')#

Cutout IRF map.

Parameters:

positionSkyCoord: Center position of the cutout region.
widthtuple of Angle: Angular sizes of the region in (lon, lat) in that specific order. If only one value is passed, a square region is extracted.
mode{‘trim’, ‘partial’, ‘strict’}, optional: Mode option for Cutout2D, for details see Cutout2D. Default is “trim”.

Returns:

cutoutIRFMap: Cutout IRF map.

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

Downsample the spatial dimension by a given factor.

Parameters:

factorint: Downsampling factor.
axis_namestr: Axis to downsample. By default, spatial axes are downsampled.
weightsMap, optional: Map with weights downsampling. Default is None.

Returns:

mapIRFMap: Downsampled IRF map.

classmethod from_diagonal_response(energy_axis, energy_axis_true, geom=None)[source]#

Create an energy dispersion map with diagonal response.

Parameters:

energy_axisMapAxis: Energy axis.
energy_axis_trueMapAxis: True energy axis
geomGeom, optional: The (2D) geometry object to use. If None, an all sky geometry with 2 bins is created. Default is None.

Returns:

edisp_mapEDispKernelMap: Energy dispersion kernel map.

classmethod from_edisp_kernel(edisp, geom=None)[source]#

Create an energy dispersion map from the input 1D kernel.

The kernel will be duplicated over all spatial bins.

Parameters:

edispEDispKernel: The input 1D kernel.
geomGeom, optional: The (2D) geometry object to use. If None, an all sky geometry with 2 bins is created. Default is None.

Returns:

edisp_mapEDispKernelMap: Energy dispersion kernel map.

classmethod from_gauss(energy_axis, energy_axis_true, sigma, bias, pdf_threshold=1e-06, geom=None)[source]#

Create an energy dispersion map from the input 1D kernel.

The kernel will be duplicated over all spatial bins.

Parameters:

energy_axis_trueQuantity: Bin edges of true energy axis.
energy_axisQuantity: Bin edges of reconstructed energy axis.
biasfloat or ndarray: Center of Gaussian energy dispersion, bias.
sigmafloat or ndarray: RMS width of Gaussian energy dispersion, resolution.
pdf_thresholdfloat, optional: Zero suppression threshold. Default is 1e-6.
geomGeom, optional: The (2D) geometry object to use. If None, an all sky geometry with 2 bins is created. Default is None.

Returns:

edisp_mapEDispKernelMap: Energy dispersion kernel map.

classmethod from_geom(geom)[source]#

Create energy dispersion map from geometry.

By default, a diagonal energy dispersion matrix is created.

Parameters:

geomGeom: Energy dispersion map geometry.

Returns:

edisp_mapEDispKernelMap: Energy dispersion kernel map.

classmethod from_hdulist(hdulist, hdu=None, hdu_bands=None, exposure_hdu=None, exposure_hdu_bands=None, format='gadf')#

Create from HDUList.

Parameters:

hdulistHDUList: HDU list.
hdustr, optional: Name or index of the HDU with the IRF map. Default is None.
hdu_bandsstr, optional: Name or index of the HDU with the IRF map BANDS table. Default is None.
exposure_hdustr, optional: Name or index of the HDU with the exposure map data. Default is None.
exposure_hdu_bandsstr, optional: Name or index of the HDU with the exposure map BANDS table. Default is None.
format{“gadf”, “gtpsf”}, optional: File format. Default is “gadf”.

Returns:

irf_mapIRFMap: IRF map.

get_edisp_kernel(position=None, energy_axis=None)[source]#

Get energy dispersion at a given position.

Parameters:

positionSkyCoord or SkyRegion, optional: The target position. Should be a single coordinates. Default is None.
energy_axisMapAxis, optional: Reconstructed energy axis, only used for checking. Default is None.

Returns:

edispEnergyDispersion: The energy dispersion (i.e. rmf object).

peek(figsize=(15, 5))[source]#

Quick-look summary plots.

Plots corresponding to the center of the map.

Parameters:

figsizetuple, optional: Size of the figure. Default is (15, 5).

classmethod read(filename, format='gadf', hdu=None, checksum=False)#

Read an IRF_map from file and create corresponding object.

Parameters:

filenamestr or Path: File name.
format{“gadf”, “gtpsf”}, optional: File format. Default is “gadf”.
hdustr or int: HDU location. Default is None.
checksumbool: If True checks both DATASUM and CHECKSUM cards in the file headers. Default is False.

Returns:

irf_mapPSFMap, EDispMap or EDispKernelMap: IRF map.

resample_energy_axis(energy_axis, weights=None)[source]#

Return a resampled EDispKernelMap.

Bins are grouped according to the edges of the reconstructed energy axis provided. The true energy is left unchanged.

Parameters:

energy_axisMapAxis: The reconstructed energy axis to use for the grouping.
weights: `~gammapy.maps.Map`, optional: Weights to be applied. Default is None.

Returns:

edispEDispKernelMap: Energy dispersion kernel map.

slice_by_idx(slices)#

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 dictionary are kept unchanged.

Returns:

map_outIRFMap: Sliced IRF map object.

stack(other, weights=None, nan_to_num=True)#

Stack IRF map with another one in place.

Parameters:

otherIRFMap: IRF map to be stacked with this one.
weightsMap, optional: Map with stacking weights. Default is None.
nan_to_num: bool, optional: Non-finite values are replaced by zero if True. Default is True.

to_hdulist(format='gadf')#

Convert to HDUList.

Parameters:

format{“gadf”, “gtpsf”}, optional: File format. Default is “gadf”.

Returns:

hdu_listHDUList: HDU list.

to_image(weights=None)[source]#

Return a 2D EdispKernelMap by summing over the reconstructed energy axis.

Parameters:

weights: `~gammapy.maps.Map`, optional: Weights to be applied. Default is None.

Returns:

edispEDispKernelMap: Energy dispersion kernel map.

to_region_nd_map(region)#

Extract IRFMap in a given region or position.

If a region is given a mean IRF is computed, if a position is given the IRF is interpolated.

Parameters:

regionSkyRegion or SkyCoord: Region or position where to get the map.

Returns:

irfIRFMap: IRF map with region geometry.

write(filename, overwrite=False, format='gadf', checksum=False)#

Write IRF map to fits.

Parameters:

filenamestr or Path: Filename to write to.
overwritebool, optional: Overwrite existing file. Default is False.
format{“gadf”, “gtpsf”}, optional: File format. Default is “gadf”.
checksumbool, optional: When True adds both DATASUM and CHECKSUM cards to the headers written to the file. Default is False.