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Last modified: December 2010

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AHELP for CIAO 4.3 Sherpa v1


Context: data


Return the data and preferences defining an ARF plot


get_arf_plot( [id, resp_id] )


The get_arf_plot() command returns the data and preferences which define a plot of ARF (auxiliary response function) data in a Sherpa session. Once an ARF associated with a data set is loaded, this command can be used to list the x, y, x error, and y error data arrays used in the ARF plot created with plot_arf() or plot(), in addition to the values for the x label, y label, title, and other plotting preferences. The information returned by get_arf_plot() may be stored in a variable, or printed to the screen, as shown in the examples section.

  • id - the id of the dataset to use; if not given, uses the default dataset id (id=1 by default, see "ahelp get_default_id")
  • resp_id - the id of the ARF to use, e.g. if more than one is associated with the data set; default is the first ARF loaded for the given data set ID (resp_id=1)


  • title - title of plot
  • xlabel - x axis label
  • ylabel - y axis label
  • units - units of grid
  • xlo - grid array, low bins
  • xhi - grid array, high bins
  • flux - unconvolved counts
  • y - convolved counts
  • plot_prefs - dictionary of plotting preferences

Example 1

sherpa> print(get_arf_plot())

When called with no arguments within the print() command, get_arf_plot() returns the data and preferences associated with the plot of the first ARF loaded for data set 1.

sherpa> print(get_arf_plot())
x      = [  0.305   0.315   0.325 ...,  10.975  10.985  10.995]
y      = [ 24.6003  59.3127  73.6197 ...,   0.6435   0.6227   0.6021]
yerr   = None
xerr   = [ 0.01  0.01  0.01 ...,  0.01  0.01  0.01]
xlabel = Energy (keV)
ylabel = cm^2
title  = source.arf
plot_prefs = {'symbolstyle': 0, 'linethickness': 3, 'linestyle': 1, 'linecolor': 'red'}

Example 2

sherpa> arf_plot=get_arf_plot(3, 2)

This command stores to the variable "arf_plot" the data and preferences defining the plot of the second ARF loaded for data set 3. The contents may be printed with 'print(arf_plot)'.

Example 3

sherpa> get_arf_plot().plot_prefs

This command lists the library of plotting preferences available for get_arf_plot(), and can be used to modify the plot settings:

sherpa> get_arf_plot().plot_prefs
            {'linecolor': 'red', 'linestyle': 1, 'linethickness': 3, 'symbolstyle': 0}

sherpa> get_arf_plot().plot_prefs["linestyle"]=3

sherpa> get_arf_plot().plot_prefs
            {'linecolor': 'red', 'linestyle': 3, 'linethickness': 3, 'symbolstyle': 0}


See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.

See Also

get_conf, get_covar, get_int_proj, get_int_unc, get_proj, get_reg_proj, get_reg_unc
get_chart_spectrum, get_data_prof, get_data_prof_prefs, get_delchi_prof, get_delchi_prof_prefs, get_fit_prof, get_model_prof, get_model_prof_prefs, get_resid_prof, get_resid_prof_prefs, get_source_prof, get_source_prof_prefs, plot_chart_spectrum, prof_data, prof_delchi, prof_fit, prof_fit_delchi, prof_fit_resid, prof_model, prof_resid, prof_source
get_areascal, get_arf, get_axes, get_backscal, get_bkg, get_bkg_plot, get_bkg_scale, get_coord, get_counts, get_data, get_data_plot, get_dep, get_dims, get_error, get_exposure, get_grouping, get_indep, get_quality, get_rmf, get_specresp, get_staterror, get_syserror
calc_stat_info, get_fit, get_stat_info
get_default_id, list_stats
get_iter_method_name, get_iter_method_opt, get_method
get_model, get_model_component, get_model_component_image, get_model_component_plot, get_model_plot, get_num_par, get_order_plot, get_par, get_pileup_model, get_response, get_source, get_source_component_image, get_source_component_plot, image_source
get_energy_flux_hist, get_photon_flux_hist, get_split_plot, plot, plot_arf, plot_bkg, plot_chisqr, plot_data, plot_delchi, plot_energy_flux, plot_fit, plot_model, plot_model_component, plot_order, plot_photon_flux, plot_ratio, plot_resid, plot_source, plot_source_component, set_xlinear, set_xlog, set_ylinear, set_ylog
get_kernel, get_psf, plot_kernel
get_chisqr_plot, get_delchi_plot, get_stat
get_analysis, get_rate
contour_resid, get_ratio, get_resid, image_getregion

Last modified: December 2010
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