get_energy_flux_hist¶
-
sherpa.astro.ui.
get_energy_flux_hist
(lo=None, hi=None, id=None, num=7500, bins=75, correlated=False, numcores=None, bkg_id=None, **kwargs)¶ Return the data displayed by plot_energy_flux.
The get_energy_flux_hist() function calculates a histogram of simulated energy flux values representing the energy flux probability distribution for a model component, accounting for the errors on the model parameters.
Parameters: - lo (number, optional) – The lower limit to use when summing up the signal. If not given then the lower value of the data grid is used.
- hi (optional) – The upper limit to use when summing up the signal. If not guven then the upper value of the data grid is used.
- id (int or string, optional) – The identifier of the data set to use. The default value
(
None
) means that the default identifier, as returned by get_default_id, is used. - num (int, optional) – The number of samples to create. The default is 7500.
- bins (int, optional) – The number of bins to use for the histogram.
- correlated (bool, optional) – If
True
(the default isFalse
) thenscales
is the full covariance matrix, otherwise it is just a 1D array containing the variances of the parameters (the diagonal elements of the covariance matrix). - numcores (optional) – The number of CPU cores to use. The default is to use all the cores on the machine.
- bkg_id (int or string, optional) – The identifier of the background component to use. This should only be set when the line to be measured is in the background model.
- scales (array, optional) – The scales used to define the normal distributions for the
parameters. The form depends on the
correlated
parameter: whenTrue
, the array should be a symmetric positive semi-definite (N,N) array, otherwise a 1D array of length N, where N is the number of free parameters. - recalc (bool, optional) – If
True
, the default, then re-calculate the values rather than use the values from the last time the function was run.
Returns: hist – An object representing the data used to create the plot by plot_energy_flux.
Return type: a sherpa.astro.plot.EnergyFluxHistogram instance
See also
get_photon_flux_hist()
- Return the data displayed by plot_photon_flux.
plot_energy_flux()
- Display the energy flux distribution.
plot_photon_flux()
- Display the photon flux distribution.
sample_energy_flux()
- Return the energy flux distribution of a model.
sample_flux()
- Return the flux distribution of a model.
sample_photon_flux()
- Return the photon flux distribution of a model.
Examples
Get the energy flux distribution for the range 0.5 to 7 for the default data set:
>>> ehist = get_energy_flux_hist(0.5, 7, num=1000) >>> print(ehist)
Compare the 0.5 to 2 energy flux distribution from the “core” data set to the values from the “jet” data set:
>>> ehist1 = get_energy_flux_hist(0.5, 2, id='jet', num=1000) >>> ehist2 = get_energy_flux_hist(0.5, 2, id='core', num=1000)