save_staterror

sherpa.ui.save_staterror(id, filename=None, clobber=False, sep=' ', comment='#', linebreak='\n', format='%g')

Save the statistical errors to a file.

If the statistical errors have not been set explicitly, then the values calculated by the statistic - such as chi2gehrels or chi2datavar - will be used.

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.
  • clobber (bool, optional) – If filename 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).
  • sep (str, optional) – The separator character. The default is ' '.
  • comment (str, optional) – The comment character. The default is '#'.
  • linebreak (str, optional) – Indicate a new line. The default is '\n'.
  • format (str, optional) – The format used to write out the numeric values. The default is '%g%'.
Raises:

sherpa.utils.err.IOErr – If filename already exists and clobber is False.

See also

load_staterror()
Load the statistical errors from a file.
save_error()
Save the errors to a file.
save_syserror()
Save the systematic 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 X and STAT_ERR.

Examples

Write out the statistical errors from the default data set to the file ‘errs.dat’.

>>> save_staterror('errs.dat')

Over-write the file it it already exists, and take the data from the data set “jet”:

>>> save_staterror('jet', 'err.out', clobber=True)