sherpa.utils.create_expr(vals, mask=None, format='%s', delim='-')[source] [edit on github]

Create a string representation of a filter.

Use the mask to convert the input values into a set of comma-separated filters - low value and high value, separated by the delimeter - that represent the data. If the mask is not given then the values must be “channel” values (that is, two values are consecutive if there difference is 1).

  • vals (sequence) – The values that represent the sequence if mask is not None, otherwise the selected channel numbers (in this case integer values).

  • mask (sequence of bool or None, optional) – The mask setting for the full dataset, without any filtering applied. A value of True indicates the element is included and False means it is excluded.

  • format (str, optional) – The format used to display each value.

  • delim (str, optional) – The separator for a range.


ValueError – If the vals and mask sequences do not match: the length of vals must equal the number of True values in mask.

See also

create_expr_integrated, parse_expr


>>> create_expr([1, 2, 3, 4])
>>> create_expr([1, 2, 4, 5, 7])
>>> create_expr([1, 2, 3, 4], [True, True, True, True])
>>> create_expr([0.1, 0.2, 0.4, 0.8], [True, True, True, True])
>>> create_expr([0.1, 0.2, 0.4, 0.8], [True, True, True, False, False, True])