'BinOp' object has no attribute 'value' Issue while calling global functions in eval and importing numpy

[anjsudh]

import pandas as pd
from  numpy import *
pd.eval("floor(1)")
Output: 1.0
pd.eval("floor(1+2)")
Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "/Users/sanjana/simulation-service/venv/lib/python3.7/site-packages/pandas/core/computation/eval.py", line 291, in eval
    truediv=truediv)
  File "/Users/sanjana/simulation-service/venv/lib/python3.7/site-packages/pandas/core/computation/expr.py", line 739, in __init__
    self.terms = self.parse()
  File "/Users/sanjana/simulation-service/venv/lib/python3.7/site-packages/pandas/core/computation/expr.py", line 756, in parse
    return self._visitor.visit(self.expr)
  File "/Users/sanjana/simulation-service/venv/lib/python3.7/site-packages/pandas/core/computation/expr.py", line 321, in visit
    return visitor(node, **kwargs)
  File "/Users/sanjana/simulation-service/venv/lib/python3.7/site-packages/pandas/core/computation/expr.py", line 327, in visit_Module
    return self.visit(expr, **kwargs)
  File "/Users/sanjana/simulation-service/venv/lib/python3.7/site-packages/pandas/core/computation/expr.py", line 321, in visit
    return visitor(node, **kwargs)
  File "/Users/sanjana/simulation-service/venv/lib/python3.7/site-packages/pandas/core/computation/expr.py", line 330, in visit_Expr
    return self.visit(node.value, **kwargs)
  File "/Users/sanjana/simulation-service/venv/lib/python3.7/site-packages/pandas/core/computation/expr.py", line 321, in visit
    return visitor(node, **kwargs)
  File "/Users/sanjana/simulation-service/venv/lib/python3.7/site-packages/pandas/core/computation/expr.py", line 579, in visit_Call_35
    new_args = [self.visit(arg).value for arg in node.args]
  File "/Users/sanjana/simulation-service/venv/lib/python3.7/site-packages/pandas/core/computation/expr.py", line 579, in <listcomp>
    new_args = [self.visit(arg).value for arg in node.args]
AttributeError: 'BinOp' object has no attribute 'value'

[WillAyd]

Thanks for the report. Investigation and PRs are always welcome

[SurajH1]

take

[SurajH1]

After looking at the documentation, I noticed that evaluating global functions is not an explicit property of pd.eval(). However, it does seem like a useful addition and something that should be a property of the function. @WillAyd can we also add a request to update documentation?

[mroeschke]

This looks to work on master, I suppose it could use a test.

In [19]: pd.__version__
Out[19]: '1.1.0.dev0+1390.gf3fdab389'

In [20]: pd.eval("floor(1)")
    ...:
Out[20]: 1.0

In [21]: pd.eval("floor(1+2)")
Out[21]: 3.0

[vmuriart]

@mroeschke I downloaded and setup the latest master branch locally to test this, and didn't get it to work.

Using:

import pandas as pd
from  numpy import *

print("Version:", pd.__version__)
print()

r = pd.eval("floor(1)")
print("Test1:", r)

r = pd.eval("floor(1+5)")
print("Test2:", r)

I still get the original error:

Version: 1.1.0.dev0+1575.gee1efb6d9

Test1: 1.0
Traceback (most recent call last):
  File "test_pd_parse.py", line 10, in <module>
    r = pd.eval("floor(1+5)")
  File "c:\users\vmuriart\desktop\pandas\pandas\pandas\core\computation\eval.py", line 341, in eval
    parsed_expr = Expr(expr, engine=engine, parser=parser, env=env)
  File "c:\users\vmuriart\desktop\pandas\pandas\pandas\core\computation\expr.py", line 787, in __init__
    self.terms = self.parse()
  File "c:\users\vmuriart\desktop\pandas\pandas\pandas\core\computation\expr.py", line 806, in parse
    return self._visitor.visit(self.expr)
  File "c:\users\vmuriart\desktop\pandas\pandas\pandas\core\computation\expr.py", line 398, in visit
    return visitor(node, **kwargs)
  File "c:\users\vmuriart\desktop\pandas\pandas\pandas\core\computation\expr.py", line 404, in visit_Module
    return self.visit(expr, **kwargs)
  File "c:\users\vmuriart\desktop\pandas\pandas\pandas\core\computation\expr.py", line 398, in visit
    return visitor(node, **kwargs)
  File "c:\users\vmuriart\desktop\pandas\pandas\pandas\core\computation\expr.py", line 407, in visit_Expr
    return self.visit(node.value, **kwargs)
  File "c:\users\vmuriart\desktop\pandas\pandas\pandas\core\computation\expr.py", line 398, in visit
    return visitor(node, **kwargs)
  File "c:\users\vmuriart\desktop\pandas\pandas\pandas\core\computation\expr.py", line 677, in visit_Call
    new_args = [self.visit(arg).value for arg in node.args]
  File "c:\users\vmuriart\desktop\pandas\pandas\pandas\core\computation\expr.py", line 677, in <listcomp>
    new_args = [self.visit(arg).value for arg in node.args]
AttributeError: 'BinOp' object has no attribute 'value'

[SurajH1]

@mroeschke The issue is raised if you include the line:

from numpy import *
but there is no error if you do not import the library.

[mirekphd]

I've just found out that this issue can be caused by trying to parse formulas referring to an empty pandas df column (i.e. column entirely composed of NaN's):

pd.eval('df.INNOCENT1 * df.INNOCENT2 * df.GUILTY1 * df.GUILTY2', parser="python", target=df, inplace=False)

raises

*** AttributeError: 'BinOp' object has no attribute 'type'

if:

ipdb> df.GUILTY1.value_counts(dropna=False)
NaN    10000

# or:

ipdb> df.GUILTY2.value_counts(dropna=False)
NaN    10000