EDispKernelMap

class gammapy.irf.EDispKernelMap(edisp_kernel_map, exposure_map=None)

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
has_single_spatial_bin
mask_safe_image	Mask safe for the map.
required_axes
tag

Methods Summary

copy()	Copy IRF map.
cutout(position, width[, mode, min_npix])	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 EDispKernelMap 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

has_single_spatial_bin

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', min_npix=3)

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”.

min_npixbool, optional

Force width to a minimmum number of pixels. Default is 3. The default is 3 pixels so interpolation is done correctly if the binning of the IRF is larger than the width of the analysis region.

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)

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)

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)

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)

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)

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))

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 EDispKernelMap from file and create corresponding object.

Parameters:

filenamestr or Path

File name.

format{“gadf”, “gtdrm”}, optional

File format. Default is “gadf”. Format “gtdrm” creates an EDispKernelMap including a single EDispKernel.

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:

edispEDispKernelMap

Energy dispersion kernel map.

resample_energy_axis(energy_axis, weights=None)

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)

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.