Synopsis
Save the errors to a file.
Syntax
save_error(id, filename=None, bkg_id=None, ascii=True, clobber=False) id - int or str, optional filename - str bkg_id - int or str, optional ascii - bool, optional clobber - bool, optional
Description
The total errors for a data set are the quadrature combination of the statistical and systematic errors. The systematic errors can be 0. If the statistical errors have not been set explicitly, then the values calculated by the statistic - such as chi2gehrels or chi2datavar - will be used.
Examples
Example 1
Write out the errors from the default data set to the file 'errs.dat'.
>>> save_error('errs.dat')Example 2
Over-write the file it it already exists, and take the data from the data set "jet":
>>> save_error('jet', 'err.out', clobber=True)Example 3
Write the data out in FITS format:
>>> save_error('err.fits', ascii=False)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` . |
| filename | The name of the file to write the array to. The format is determined by the `ascii` argument. |
| bkg_id | Set if the background should be written out rather than the source. |
| ascii | If False then the data is written as a FITS format binary table. The default is True . The exact format of the output file depends on the I/O library in use (Crates or AstroPy). |
| clobber | If `outfile` is not none , then this flag controls whether an existing file can be overwritten ( True ) or if it raises an exception ( False , the default setting). |
Notes
The function does not follow the normal Python standards for parameter use, since it is designed for easy interactive use. When called with a single un-named argument, it is taken to be the `filename` parameter. If given two un-named arguments, then they are interpreted as the `id` and `filename` parameters, respectively. The remaining parameters are expected to be given as named arguments.
The output file contains the columns x and err .
Bugs
See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.
See Also
- contrib
- save_chart_spectrum, save_marx_spectrum
- data
- copy_data, dataspace1d, dataspace2d, datastack, delete_data, fake, get_axes, get_bkg_chisqr_plot, get_bkg_delchi_plot, get_bkg_fit_plot, get_bkg_model_plot, get_bkg_plot, get_bkg_ratio_plot, get_bkg_resid_plot, get_bkg_source_plot, 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_quality, get_specresp, get_staterror, get_syserror, group, group_adapt, group_adapt_snr, group_bins, group_counts, group_snr, group_width, load_arf, load_arrays, load_ascii, load_bkg, load_bkg_arf, load_bkg_rmf, load_data, load_grouping, load_image, load_multi_arfs, load_multi_rmfs, load_pha, load_quality, load_rmf, load_staterror, load_syserror, load_table, pack_image, pack_pha, pack_table, set_data, set_quality, ungroup, unpack_arf, unpack_arrays, unpack_ascii, unpack_bkg, unpack_data, unpack_image, unpack_pha, unpack_rmf, unpack_table
- filtering
- get_filter, load_filter, set_filter
- info
- get_default_id, list_bkg_ids, list_data_ids, list_response_ids
- modeling
- add_model, add_user_pars, clean, load_table_model, load_template_interpolator, load_template_model, load_user_model, save_model, save_source
- plotting
- plot_data, set_xlinear, set_xlog, set_ylinear, set_ylog
- saving
- restore, save, save_all, save_arrays, save_data, save_delchi, save_filter, save_grouping, save_image, save_pha, save_quality, save_resid, save_staterror, save_syserror, save_table, script
- statistics
- load_user_stat
- utilities
- calc_data_sum, calc_data_sum2d, calc_ftest, calc_kcorr, calc_mlr, calc_model_sum2d, calc_source_sum2d, get_rate
- visualization
- contour, contour_data, contour_ratio, histogram1d, histogram2d, image_data, rebin