pandas.DataFrame.eval

DataFrame.eval(expr, inplace=False, **kwargs) [source]

Evaluate an expression in the context of the calling DataFrame instance.

Parameters:	expr : string The expression string to evaluate. inplace : bool, default False If the expression contains an assignment, whether to perform the operation inplace and mutate the existing DataFrame. Otherwise, a new DataFrame is returned. New in version 0.18.0. kwargs : dict See the documentation for eval() for complete details on the keyword arguments accepted by query().
Returns:	ret : ndarray, scalar, or pandas object

See also

pandas.DataFrame.query, pandas.DataFrame.assign, pandas.eval

Notes

For more details see the API documentation for eval(). For detailed examples see enhancing performance with eval.

Examples

>>> from numpy.random import randn
>>> from pandas import DataFrame
>>> df = DataFrame(randn(10, 2), columns=list('ab'))
>>> df.eval('a + b')
>>> df.eval('c = a + b')