sherpa.ui.load_data(id, filename=None, ncols=2, colkeys=None, dstype=<class 'sherpa.data.Data1D'>, sep=' ', comment='#', require_floats=True)

Load a data set from an ASCII file.

  • id (int or str) – The identifier for the data set to use.

  • filename (str) – The name of the ASCII file to read in.

  • ncols (int, optional) – The number of columns to read in (the first ncols columns in the file).

  • colkeys (array of str, optional) – An array of the column name to read in. The default is None.

  • dstype (data class to use, optional) – What type of data is to be used. Supported values include Data1D (the default), Data1DInt, Data2D, and Data2DInt.

  • sep (str, optional) – The separator character. The default is ' '.

  • comment (str, optional) – The comment character. The default is '#'.

  • require_floats (bool, optional) – If True (the default), non-numeric data values will raise a ValueError.


ValueError – If a column value can not be converted into a numeric value and the require_floats parameter is True.

See also


Return the data set by identifier.


Create a data set from array values.


Create a sherpa data object from arrays of data.


Create a sherpa data object from a file.


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.

See unpack_data for a description of the supported file format.


>>> load_data('tbl.dat')
>>> load_data('hist.dat', dstype=Data1DInt)
>>> cols = ['rmid', 'sur_bri', 'sur_bri_err']
>>> load_data(2, 'profile.dat', colkeys=cols)