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
Returns: ret : ndarray, scalar, or pandas object
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')