FluxPoints

class gammapy.spectrum.FluxPoints(table)

Bases: object

Flux point object.

For a complete documentation see SED, for an usage example see Flux point computation.

Parameters:

table : Table

Input data table, with the following minimal required columns:

• Format 'dnde': 'dnde' and 'e_ref'
• Format 'flux': 'flux', 'e_min', 'e_max'
• Format 'eflux': 'eflux', 'e_min', 'e_max'

Examples

>>> from gammapy.spectrum import FluxPoints
>>> filename = '$GAMMAPY_EXTRA/test_datasets/spectrum/flux_points/flux_points.fits'
>>> flux_points = FluxPoints.read(filename)
>>> flux_points.show()

Attributes Summary

e_max	Upper bound of energy bin.
e_min	Lower bound of energy bin.
e_ref	Reference energy.
sed_type	Flux points sed type.

Methods Summary

drop_ul()	Drop upper limit flux points.
get_energy_err([sed_type])	Compute energy error for given sed type
get_flux_err([sed_type])	Compute flux error for given sed type
info()	Print flux points info.
peek([figsize])	Show flux points.
plot([ax, sed_type, energy_unit, flux_unit, ...])	Plot flux points
read(filename, **kwargs)	Read flux points.
stack(flux_points)	Create a new FluxPoints object by stacking a list of existing flux points.
write(filename, **kwargs)	Write flux points.

Attributes Documentation

e_max

Upper bound of energy bin.

Defined by e_max column in FluxPoints.table.

Returns:

e_max : Quantity

Upper bound of energy bin.

e_min

Lower bound of energy bin.

Defined by e_min column in FluxPoints.table.

Returns:

e_min : Quantity

Lower bound of energy bin.

e_ref

Reference energy.

Defined by e_ref column in FluxPoints.table or computed as log center, if e_min and e_max columns are present in FluxPoints.table.

Returns:

e_ref : Quantity

Reference energy.

sed_type

Flux points sed type.

Returns:

sed_type : str

Can be either ‘dnde’, ‘e2dnde’, ‘flux’ or ‘eflux’.

Methods Documentation

drop_ul()

Drop upper limit flux points.

Returns:

flux_points : FluxPoints

Flux points with upper limit points removed.

Examples

from gammapy.spectrum import FluxPoints

filename = ‘$GAMMAPY_EXTRA/test_datasets/spectrum/flux_points/flux_points.fits’ flux_points = FluxPoints.read(filename)

print(flux_points) print(flux_points.drop_ul())

get_energy_err(sed_type=None)

Compute energy error for given sed type

get_flux_err(sed_type=None)

Compute flux error for given sed type

info()

Print flux points info.

peek(figsize=(8, 5), **kwargs)

Show flux points.

Parameters:

figsize : tuple

Figure size

kwargs : dict

Keyword arguments passed to FluxPoints.plot().

Returns:

ax : Axes

Plotting axes object.

plot(ax=None, sed_type=None, energy_unit='TeV', flux_unit=None, energy_power=0, **kwargs)

Plot flux points

Parameters:

ax : Axes

Axis object to plot on.

sed_type : [‘dnde’, ‘flux’, ‘eflux’]

Which sed type to plot.

energy_unit : str, Unit, optional

Unit of the energy axis

flux_unit : str, Unit, optional

Unit of the flux axis

energy_power : int

Power of energy to multiply y axis with

kwargs : dict

Keyword arguments passed to errorbar()

Returns:

ax : Axes

Axis object

classmethod read(filename, **kwargs)

Read flux points.

Parameters:

filename : str

Filename

kwargs : dict

Keyword arguments passed to read.

classmethod stack(flux_points)

Create a new FluxPoints object by stacking a list of existing flux points.

The first FluxPoints object in the list is taken as a reference to infer column names and units for the stacked object.

Parameters:

flux_points : list of FluxPoints objects

List of flux points to stack.

Returns:

flux_points : FluxPoints

Flux points without upper limit points.

write(filename, **kwargs)

Write flux points.

Parameters:

filename : str

Filename

kwargs : dict

Keyword arguments passed to write.