From 607529700a371b3ed2f67a942ef3fb491e6346ea Mon Sep 17 00:00:00 2001
From: Marco Gorelli <m.e.gorelli@gmail.com>
Date: Mon, 2 Nov 2020 14:14:18 +0000
Subject: [PATCH] refactor core/computation
---
pandas/core/computation/align.py | 12 +++++++-----
pandas/core/computation/eval.py | 11 +++++------
pandas/core/computation/expr.py | 17 ++++++++---------
pandas/core/computation/pytables.py | 16 ++++++++--------
pandas/core/computation/scope.py | 3 +--
5 files changed, 29 insertions(+), 30 deletions(-)
diff --git a/pandas/core/computation/align.py b/pandas/core/computation/align.py
index 82867cf9dcd29..8a8b0d564ea49 100644
--- a/pandas/core/computation/align.py
+++ b/pandas/core/computation/align.py
@@ -38,8 +38,7 @@ def _align_core_single_unary_op(
def _zip_axes_from_type(
typ: Type[FrameOrSeries], new_axes: Sequence[int]
) -> Dict[str, int]:
- axes = {name: new_axes[i] for i, name in enumerate(typ._AXIS_ORDERS)}
- return axes
+ return {name: new_axes[i] for i, name in enumerate(typ._AXIS_ORDERS)}
def _any_pandas_objects(terms) -> bool:
@@ -186,8 +185,11 @@ def reconstruct_object(typ, obj, axes, dtype):
# The condition is to distinguish 0-dim array (returned in case of
# scalar) and 1 element array
# e.g. np.array(0) and np.array([0])
- if len(obj.shape) == 1 and len(obj) == 1:
- if not isinstance(ret_value, np.ndarray):
- ret_value = np.array([ret_value]).astype(res_t)
+ if (
+ len(obj.shape) == 1
+ and len(obj) == 1
+ and not isinstance(ret_value, np.ndarray)
+ ):
+ ret_value = np.array([ret_value]).astype(res_t)
return ret_value
diff --git a/pandas/core/computation/eval.py b/pandas/core/computation/eval.py
index b77204861f0a4..12f16343362e2 100644
--- a/pandas/core/computation/eval.py
+++ b/pandas/core/computation/eval.py
@@ -52,12 +52,11 @@ def _check_engine(engine: Optional[str]) -> str:
# TODO: validate this in a more general way (thinking of future engines
# that won't necessarily be import-able)
# Could potentially be done on engine instantiation
- if engine == "numexpr":
- if not NUMEXPR_INSTALLED:
- raise ImportError(
- "'numexpr' is not installed or an unsupported version. Cannot use "
- "engine='numexpr' for query/eval if 'numexpr' is not installed"
- )
+ if engine == "numexpr" and not NUMEXPR_INSTALLED:
+ raise ImportError(
+ "'numexpr' is not installed or an unsupported version. Cannot use "
+ "engine='numexpr' for query/eval if 'numexpr' is not installed"
+ )
return engine
diff --git a/pandas/core/computation/expr.py b/pandas/core/computation/expr.py
index 8c56f02c8d3cc..c971551a7f400 100644
--- a/pandas/core/computation/expr.py
+++ b/pandas/core/computation/expr.py
@@ -496,15 +496,14 @@ def _maybe_evaluate_binop(
f"'{lhs.type}' and '{rhs.type}'"
)
- if self.engine != "pytables":
- if (
- res.op in CMP_OPS_SYMS
- and getattr(lhs, "is_datetime", False)
- or getattr(rhs, "is_datetime", False)
- ):
- # all date ops must be done in python bc numexpr doesn't work
- # well with NaT
- return self._maybe_eval(res, self.binary_ops)
+ if self.engine != "pytables" and (
+ res.op in CMP_OPS_SYMS
+ and getattr(lhs, "is_datetime", False)
+ or getattr(rhs, "is_datetime", False)
+ ):
+ # all date ops must be done in python bc numexpr doesn't work
+ # well with NaT
+ return self._maybe_eval(res, self.binary_ops)
if res.op in eval_in_python:
# "in"/"not in" ops are always evaluated in python
diff --git a/pandas/core/computation/pytables.py b/pandas/core/computation/pytables.py
index dd622ed724e8f..6ec637a8b4845 100644
--- a/pandas/core/computation/pytables.py
+++ b/pandas/core/computation/pytables.py
@@ -378,14 +378,14 @@ def prune(self, klass):
operand = self.operand
operand = operand.prune(klass)
- if operand is not None:
- if issubclass(klass, ConditionBinOp):
- if operand.condition is not None:
- return operand.invert()
- elif issubclass(klass, FilterBinOp):
- if operand.filter is not None:
- return operand.invert()
-
+ if operand is not None and (
+ issubclass(klass, ConditionBinOp)
+ and operand.condition is not None
+ or not issubclass(klass, ConditionBinOp)
+ and issubclass(klass, FilterBinOp)
+ and operand.filter is not None
+ ):
+ return operand.invert()
return None
diff --git a/pandas/core/computation/scope.py b/pandas/core/computation/scope.py
index 2925f583bfc56..7a9b8caa985e3 100644
--- a/pandas/core/computation/scope.py
+++ b/pandas/core/computation/scope.py
@@ -144,8 +144,7 @@ def __init__(
def __repr__(self) -> str:
scope_keys = _get_pretty_string(list(self.scope.keys()))
res_keys = _get_pretty_string(list(self.resolvers.keys()))
- unicode_str = f"{type(self).__name__}(scope={scope_keys}, resolvers={res_keys})"
- return unicode_str
+ return f"{type(self).__name__}(scope={scope_keys}, resolvers={res_keys})"
@property
def has_resolvers(self) -> bool: