Last modified: December 2020

URL: https://cxc.cfa.harvard.edu/sherpa/ahelp/get_exposure.html
AHELP for CIAO 4.13 Sherpa v1

get_exposure

Context: data

Synopsis

Return the exposure time of a PHA data set.

Syntax

get_exposure(id=None, bkg_id=None)

id - int or str, optional
bkg_id - int or str, optional

Description

The exposure time of a PHA data set is taken from the EXPTIME keyword in its header, but it can be changed once the file has been loaded.


Examples

Example 1

Return the exposure time for the default data set.

>>> t = get_exposure()

Example 2

Return the exposure time for the data set with identifier 2:

>>> t2 = get_exposure(2)

Example 3

Return the exposure time for the first background component of data set "core":

>>> tbkg = get_exposure('core', bkg_id=1)

PARAMETERS

The parameters for this function are:

Parameter Definition
id The identifier for the data set to use. If not given then the default identifier is used, as returned by `get_default_id` .
bkg_id Set to identify which background component to use. The default value ( none ) means that the time is for the source component of the data set.

Return value

The return value from this function is:

exposure -- The exposure time, in seconds.


Bugs

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

See Also

confidence
get_conf, get_conf_results, get_covar, get_covar_opt, get_covar_results, get_covariance_results, get_int_proj, get_int_unc, get_proj, get_proj_opt, get_proj_results, get_projection_results, get_reg_proj, get_reg_unc
contrib
get_chart_spectrum, get_marx_spectrum
data
get_areascal, get_arf, get_arf_plot, get_axes, get_backscal, get_bkg, get_bkg_arf, get_bkg_chisqr_plot, get_bkg_delchi_plot, get_bkg_fit_plot, get_bkg_model, get_bkg_model_plot, get_bkg_plot, get_bkg_ratio_plot, get_bkg_resid_plot, get_bkg_rmf, get_bkg_scale, get_bkg_source, get_bkg_source_plot, get_coord, get_counts, get_data, get_data_contour, get_data_contour_prefs, get_data_image, get_data_plot, get_data_plot_prefs, get_dep, get_dims, get_error, get_grouping, get_indep, get_quality, get_rmf, get_specresp, get_staterror, get_syserror, set_exposure
filtering
get_filter
fitting
calc_stat_info, get_stat_info
info
get_default_id, list_stats
methods
get_draws, get_iter_method_name, get_iter_method_opt, get_method, get_method_name, get_method_opt
modeling
get_model, get_model_component, get_model_component_image, get_model_component_plot, get_model_plot, get_num_par, get_num_par_frozen, get_num_par_thawed, get_order_plot, get_par, get_pileup_model, get_response, get_source, get_source_component_image, get_source_component_plot, get_source_contour, get_source_image, get_source_plot, image_source
plotting
get_split_plot
psfs
get_psf, get_psf_contour, get_psf_image, get_psf_plot
statistics
get_chisqr_plot, get_delchi_plot, get_prior, get_sampler, get_stat, get_stat_name
utilities
get_analysis, get_rate
visualization
image_getregion