save_syserror¶
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sherpa.astro.ui.save_syserror(id, filename=None, bkg_id=None, ascii=True, clobber=False)¶ Save the systematic errors to a file.
Parameters: - id (int or str, optional) – The identifier for the data set to use. If not given then the default identifier is used, as returned by get_default_id.
- filename (str) – The name of the file to write the array to. The format is determined by the ascii argument.
- bkg_id (int or str, optional) – Set if the background should be written out rather than the source.
- ascii (bool, optional) – If
Falsethen the data is written as a FITS format binary table. The default isTrue. The exact format of the output file depends on the I/O library in use (Crates or AstroPy). - clobber (bool, optional) – 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).
Raises: sherpa.utils.err.IOErr– If the data set does not contain any systematic errors.sherpa.utils.err.DataErr– If filename already exists and clobber isFalse.
See also
load_syserror()- Load the systematic errors from a file.
save_error()- Save the errors to a file.
save_staterror()- Save the statistical errors to a file.
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
XandSYS_ERR.Examples
Write out the systematic errors from the default data set to the file ‘errs.dat’.
>>> save_syserror('errs.dat')
Over-write the file it it already exists, and take the data from the data set “jet”:
>>> save_syserror('jet', 'err.out', clobber=True)
Write the data out in FITS format:
>>> save_syserror('syserr.fits', ascii=False)