Small improvements to str_cat

pandas/__init__.py

@@ -1,5 +1,6 @@
 # pylint: disable-msg=W0614,W0401,W0611,W0622
 
+# flake8: noqa
 
 __docformat__ = 'restructuredtext'
 

pandas/_version.py

@@ -8,6 +8,8 @@
 # This file is released into the public domain. Generated by
 # versioneer-0.15 (https://github.com/warner/python-versioneer)
 
+# flake8: noqa
+
 import errno
 import os
 import re

pandas/compat/__init__.py

@@ -25,6 +25,8 @@
 * platform checker
 """
 # pylint disable=W0611
+# flake8: noqa
+
 import functools
 import itertools
 from distutils.version import LooseVersion

pandas/compat/chainmap_impl.py

@@ -58,16 +58,19 @@ def __missing__(self, key):
     def __getitem__(self, key):
         for mapping in self.maps:
             try:
-                return mapping[key]             # can't use 'key in mapping' with defaultdict
+                # can't use 'key in mapping' with defaultdict
+                return mapping[key]
             except KeyError:
                 pass
-        return self.__missing__(key)            # support subclasses that define __missing__
+        # support subclasses that define __missing__
+        return self.__missing__(key)
 
     def get(self, key, default=None):
         return self[key] if key in self else default
 
     def __len__(self):
-        return len(set().union(*self.maps))     # reuses stored hash values if possible
+        # reuses stored hash values if possible
+        return len(set().union(*self.maps))
 
     def __iter__(self):
         return iter(set().union(*self.maps))
@@ -89,7 +92,10 @@ def fromkeys(cls, iterable, *args):
         return cls(dict.fromkeys(iterable, *args))
 
     def copy(self):
-        'New ChainMap or subclass with a new copy of maps[0] and refs to maps[1:]'
+        """
+        New ChainMap or subclass with a new copy of maps[0] and refs to
+        maps[1:]
+        """
         return self.__class__(self.maps[0].copy(), *self.maps[1:])
 
     __copy__ = copy
@@ -115,21 +121,29 @@ def __delitem__(self, key):
         try:
             del self.maps[0][key]
         except KeyError:
-            raise KeyError('Key not found in the first mapping: {!r}'.format(key))
+            raise KeyError('Key not found in the first mapping: {!r}'
+                           .format(key))
 
     def popitem(self):
-        'Remove and return an item pair from maps[0]. Raise KeyError is maps[0] is empty.'
+        """
+        Remove and return an item pair from maps[0]. Raise KeyError is maps[0]
+        is empty.
+        """
         try:
             return self.maps[0].popitem()
         except KeyError:
             raise KeyError('No keys found in the first mapping.')
 
     def pop(self, key, *args):
-        'Remove *key* from maps[0] and return its value. Raise KeyError if *key* not in maps[0].'
+        """
+        Remove *key* from maps[0] and return its value. Raise KeyError if
+        *key* not in maps[0].
+        """
         try:
             return self.maps[0].pop(key, *args)
         except KeyError:
-            raise KeyError('Key not found in the first mapping: {!r}'.format(key))
+            raise KeyError('Key not found in the first mapping: {!r}'
+                           .format(key))
 
     def clear(self):
         'Clear maps[0], leaving maps[1:] intact.'

pandas/compat/openpyxl_compat.py

@@ -32,4 +32,4 @@ def is_compat(major_ver=1):
         return LooseVersion(stop_ver) <= ver
     else:
         raise ValueError('cannot test for openpyxl compatibility with ver {0}'
-                .format(major_ver))
+                         .format(major_ver))

pandas/compat/pickle_compat.py

@@ -1,5 +1,7 @@
 """ support pre 0.12 series pickle compatibility """
 
+# flake8: noqa
+
 import sys
 import numpy as np
 import pandas

pandas/computation/align.py

@@ -173,8 +173,8 @@ def _reconstruct_object(typ, obj, axes, dtype):
         ret_value = res_t.type(obj)
     else:
         ret_value = typ(obj).astype(res_t)
-        # The condition is to distinguish 0-dim array (returned in case of scalar)
-        # and 1 element array
+        # 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):

pandas/computation/api.py

@@ -1,2 +1,4 @@
+# flake8: noqa
+
 from pandas.computation.eval import eval
 from pandas.computation.expr import Expr

pandas/computation/engines.py

@@ -1,13 +1,16 @@
 """Engine classes for :func:`~pandas.eval`
 """
 
+# flake8: noqa
+
 import abc
 
 from pandas import compat
 from pandas.compat import DeepChainMap, map
 from pandas.core import common as com
 from pandas.computation.align import _align, _reconstruct_object
-from pandas.computation.ops import UndefinedVariableError, _mathops, _reductions
+from pandas.computation.ops import (UndefinedVariableError,
+                                    _mathops, _reductions)
 
 
 _ne_builtins = frozenset(_mathops + _reductions)
@@ -30,8 +33,8 @@ def _check_ne_builtin_clash(expr):
 
     if overlap:
         s = ', '.join(map(repr, overlap))
-        raise NumExprClobberingError('Variables in expression "%s" overlap with '
-                                     'numexpr builtins: (%s)' % (expr, s))
+        raise NumExprClobberingError('Variables in expression "%s" '
+                                     'overlap with builtins: (%s)' % (expr, s))
 
 
 class AbstractEngine(object):

pandas/computation/expr.py

@@ -2,11 +2,7 @@
 """
 
 import ast
-import operator
-import sys
-import inspect
 import tokenize
-import datetime
 
 from functools import partial
 
@@ -21,7 +17,7 @@
 from pandas.computation.ops import _reductions, _mathops, _LOCAL_TAG
 from pandas.computation.ops import Op, BinOp, UnaryOp, Term, Constant, Div
 from pandas.computation.ops import UndefinedVariableError, FuncNode
-from pandas.computation.scope import Scope, _ensure_scope
+from pandas.computation.scope import Scope
 
 
 def tokenize_string(source):
@@ -381,9 +377,9 @@ def _possibly_evaluate_binop(self, op, op_class, lhs, rhs,
                                                       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)):
+            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._possibly_eval(res, self.binary_ops)
@@ -392,8 +388,8 @@ def _possibly_evaluate_binop(self, op, op_class, lhs, rhs,
             # "in"/"not in" ops are always evaluated in python
             return self._possibly_eval(res, eval_in_python)
         elif self.engine != 'pytables':
-            if (getattr(lhs, 'return_type', None) == object
-                    or getattr(rhs, 'return_type', None) == object):
+            if (getattr(lhs, 'return_type', None) == object or
+                    getattr(rhs, 'return_type', None) == object):
                 # evaluate "==" and "!=" in python if either of our operands
                 # has an object return type
                 return self._possibly_eval(res, eval_in_python +
@@ -517,7 +513,8 @@ def visit_Attribute(self, node, **kwargs):
         raise ValueError("Invalid Attribute context {0}".format(ctx.__name__))
 
     def visit_Call_35(self, node, side=None, **kwargs):
-        """ in 3.5 the starargs attribute was changed to be more flexible, #11097 """
+        """ in 3.5 the starargs attribute was changed to be more flexible,
+        #11097 """
 
         if isinstance(node.func, ast.Attribute):
             res = self.visit_Attribute(node.func)
@@ -541,7 +538,7 @@ def visit_Call_35(self, node, side=None, **kwargs):
 
         if isinstance(res, FuncNode):
 
-            new_args = [ self.visit(arg) for arg in node.args ]
+            new_args = [self.visit(arg) for arg in node.args]
 
             if node.keywords:
                 raise TypeError("Function \"{0}\" does not support keyword "
@@ -551,15 +548,17 @@ def visit_Call_35(self, node, side=None, **kwargs):
 
         else:
 
-            new_args = [ self.visit(arg).value for arg in node.args ]
+            new_args = [self.visit(arg).value for arg in node.args]
 
             for key in node.keywords:
                 if not isinstance(key, ast.keyword):
                     raise ValueError("keyword error in function call "
                                      "'{0}'".format(node.func.id))
 
                 if key.arg:
-                    kwargs.append(ast.keyword(keyword.arg, self.visit(keyword.value)))
+                    # TODO: bug?
+                    kwargs.append(ast.keyword(
+                        keyword.arg, self.visit(keyword.value)))  # noqa
 
             return self.const_type(res(*new_args, **kwargs), self.env)
 

pandas/computation/expressions.py

@@ -16,9 +16,10 @@
     ver = ne.__version__
     _NUMEXPR_INSTALLED = ver >= LooseVersion('2.1')
     if not _NUMEXPR_INSTALLED:
-        warnings.warn("The installed version of numexpr {ver} is not supported "
-                      "in pandas and will be not be used\nThe minimum supported "
-                      "version is 2.1\n".format(ver=ver), UserWarning)
+        warnings.warn(
+            "The installed version of numexpr {ver} is not supported "
+            "in pandas and will be not be used\nThe minimum supported "
+            "version is 2.1\n".format(ver=ver), UserWarning)
 
 except ImportError:  # pragma: no cover
     _NUMEXPR_INSTALLED = False
@@ -96,8 +97,8 @@ def _can_use_numexpr(op, op_str, a, b, dtype_check):
     return False
 
 
-def _evaluate_numexpr(op, op_str, a, b, raise_on_error=False, truediv=True, reversed=False,
-                      **eval_kwargs):
+def _evaluate_numexpr(op, op_str, a, b, raise_on_error=False, truediv=True,
+                      reversed=False, **eval_kwargs):
     result = None
 
     if _can_use_numexpr(op, op_str, a, b, 'evaluate'):
@@ -106,7 +107,7 @@ def _evaluate_numexpr(op, op_str, a, b, raise_on_error=False, truediv=True, reve
             # we were originally called by a reversed op
             # method
             if reversed:
-                a,b = b,a
+                a, b = b, a
 
             a_value = getattr(a, "values", a)
             b_value = getattr(b, "values", b)

pandas/computation/ops.py

@@ -498,12 +498,13 @@ def return_type(self):
         if operand.return_type == np.dtype('bool'):
             return np.dtype('bool')
         if (isinstance(operand, Op) and
-            (operand.op in _cmp_ops_dict or operand.op in _bool_ops_dict)):
+                (operand.op in _cmp_ops_dict or operand.op in _bool_ops_dict)):
             return np.dtype('bool')
         return np.dtype('int')
 
 
 class MathCall(Op):
+
     def __init__(self, func, args):
         super(MathCall, self).__init__(func.name, args)
         self.func = func
@@ -518,9 +519,11 @@ def __unicode__(self):
 
 
 class FuncNode(object):
+
     def __init__(self, name):
         if name not in _mathops:
-            raise ValueError("\"{0}\" is not a supported function".format(name))
+            raise ValueError(
+                "\"{0}\" is not a supported function".format(name))
         self.name = name
         self.func = getattr(np, name)
 

pandas/computation/pytables.py

@@ -7,12 +7,11 @@
 from datetime import datetime, timedelta
 import numpy as np
 import pandas as pd
-from pandas.compat import u, string_types, PY3, DeepChainMap
+from pandas.compat import u, string_types, DeepChainMap
 from pandas.core.base import StringMixin
 import pandas.core.common as com
 from pandas.computation import expr, ops
 from pandas.computation.ops import is_term, UndefinedVariableError
-from pandas.computation.scope import _ensure_scope
 from pandas.computation.expr import BaseExprVisitor
 from pandas.computation.common import _ensure_decoded
 from pandas.tseries.timedeltas import _coerce_scalar_to_timedelta_type
@@ -147,17 +146,17 @@ def is_in_table(self):
     @property
     def kind(self):
         """ the kind of my field """
-        return getattr(self.queryables.get(self.lhs),'kind',None)
+        return getattr(self.queryables.get(self.lhs), 'kind', None)
 
     @property
     def meta(self):
         """ the meta of my field """
-        return getattr(self.queryables.get(self.lhs),'meta',None)
+        return getattr(self.queryables.get(self.lhs), 'meta', None)
 
     @property
     def metadata(self):
         """ the metadata of my field """
-        return getattr(self.queryables.get(self.lhs),'metadata',None)
+        return getattr(self.queryables.get(self.lhs), 'metadata', None)
 
     def generate(self, v):
         """ create and return the op string for this TermValue """
@@ -195,7 +194,7 @@ def stringify(value):
             return TermValue(int(v), v, kind)
         elif meta == u('category'):
             metadata = com._values_from_object(self.metadata)
-            result = metadata.searchsorted(v,side='left')
+            result = metadata.searchsorted(v, side='left')
             return TermValue(result, result, u('integer'))
         elif kind == u('integer'):
             v = int(float(v))
@@ -504,7 +503,7 @@ def __init__(self, where, op=None, value=None, queryables=None,
                 else:
                     w = self.parse_back_compat(w)
                     where[idx] = w
-            where = ' & ' .join(["(%s)" % w for w in where])
+            where = ' & ' .join(["(%s)" % w for w in where])  # noqa
 
         self.expr = where
         self.env = Scope(scope_level + 1, local_dict=local_dict)
@@ -551,12 +550,14 @@ def parse_back_compat(self, w, op=None, value=None):
 
                 # stringify with quotes these values
                 def convert(v):
-                    if isinstance(v, (datetime,np.datetime64,timedelta,np.timedelta64)) or hasattr(v, 'timetuple'):
+                    if (isinstance(v, (datetime, np.datetime64,
+                                       timedelta, np.timedelta64)) or
+                            hasattr(v, 'timetuple')):
                         return "'{0}'".format(v)
                     return v
 
-                if isinstance(value, (list,tuple)):
-                    value = [ convert(v) for v in value ]
+                if isinstance(value, (list, tuple)):
+                    value = [convert(v) for v in value]
                 else:
                     value = convert(value)