pandas.errors.UndefinedVariableError

exception pandas.errors.UndefinedVariableError(name, is_local=None)

Exception raised by query or eval when using an undefined variable name.

It will also specify whether the undefined variable is local or not.

Parameters:

namestr

The name of the undefined variable.

is_localbool or None, optional

Indicates whether the undefined variable is considered a local variable. If True, the error message specifies it as a local variable. If False or None, the variable is treated as a non-local name.

See also

DataFrame.query

Query the columns of a DataFrame with a boolean expression.

DataFrame.eval

Evaluate a string describing operations on DataFrame columns.

Examples

>>> df = pd.DataFrame({"A": [1, 1, 1]})
>>> df.query("A > x")
... # UndefinedVariableError: name 'x' is not defined
>>> df.query("A > @y")
... # UndefinedVariableError: local variable 'y' is not defined
>>> pd.eval("x + 1")
... # UndefinedVariableError: name 'x' is not defined