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Last modified: December 2013

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AHELP for CIAO 4.9 Sherpa v1


Context: plotting


Create a trace plot of iteration number vs. sampled value.


plot_trace(points [, name="x", replot=False, overplot=False,


The plot_trace() function creates trace plot of the input array of data values (a NumPy ndarray), with iteration number along the x-axis and sampled value along the y-axis. The x-axis is labeled "iteration", and the y-axis and plot title are named "x" by default (may be changed with 'name' argument).

Argument Default Description
points NumPy ndarray of histogram data values
name "x" label to assign to the y-axis of sampled values, and title to assign to the plot
replot False Should previously-calculated arrays be used to create the plot?
overplot False If True, then add the data to the current plot, otherwise erase the frame and create a new plot.
clearwindow True If True, then do not delete any existing frames in the current ChIPS window. Note that the plots will be created in a new ChIPS frame even when this argument is set.

Example 1

plot_trace(x, name="Energy Flux")

Create the trace plot for a simulated energy flux distribution returned by the sample_energy_flux() command (see 'ahelp sample_energy_flux'), using a custom y-axis label (also sets plot title).

sherpa> a = sample_energy_flux(0.5,7.,num=1000)
sherpa> plot_energy_flux()
sherpa> x = a[:,0]
sherpa> plot_trace(x, name="Energy Flux")

Example 2


Define a histogram in the variable "x" and create the corresponding trace plot of iteration number versus sampled value, with default settings.

sherpa> mu, sigma = 100, 15
sherpa> x = mu + sigma*np.random.randn(10000)
sherpa> plot_trace(x)


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

See Also

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_arf_plot, get_bkg_plot
list_model_ids, show_bkg_model, show_bkg_source
add_model, add_user_pars, clean, create_model_component, delete_bkg_model, delete_model, delete_model_component, get_model, get_model_autoassign_func, 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_source, get_source_component_image, get_source_component_plot, image_model, image_model_component, image_source, image_source_component, integrate, integrate1d, link, load_table_model, load_template_model, load_user_model, normal_sample, reset, save_model, save_source, set_bkg_model, set_full_model, set_model_autoassign_func, set_pileup_model, set_source, set_xsabund, set_xscosmo, set_xsxsect, set_xsxset, t_sample, uniform_sample
get_energy_flux_hist, get_lrt_plot, get_lrt_results, get_photon_flux_hist, get_pvalue_plot, get_pvalue_results, get_split_plot, plot, plot_arf, plot_bkg, plot_cdf, plot_chisqr, plot_data, plot_delchi, plot_energy_flux, plot_fit, plot_model, plot_model_component, plot_order, plot_pdf, plot_photon_flux, plot_pvalue, plot_ratio, plot_resid, plot_scatter, plot_source, plot_source_component, set_xlinear, set_xlog, set_ylinear, set_ylog
delete_psf, load_conv, plot_kernel
save_delchi, save_resid
get_chisqr_plot, get_delchi_plot
calc_chisqr, calc_energy_flux, calc_model_sum, calc_photon_flux, calc_source_sum, calc_stat, eqwidth
contour_model, contour_ratio, contour_resid, get_ratio, get_resid

Last modified: December 2013
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