remove core.computation.ops.Div resolves pandas-dev#21374 pandas-dev#58748

Author: Laurent Mutricy

pandas/core/computation/expr.py

@@ -32,7 +32,6 @@
     UNARY_OPS_SYMS,
     BinOp,
     Constant,
-    Div,
     FuncNode,
     Op,
     Term,
@@ -374,6 +373,7 @@ class BaseExprVisitor(ast.NodeVisitor):
         "Add",
         "Sub",
         "Mult",
+        "Div",
         None,
         "Pow",
         "FloorDiv",
@@ -537,9 +537,6 @@ def visit_BinOp(self, node, **kwargs):
         left, right = self._maybe_downcast_constants(left, right)
         return self._maybe_evaluate_binop(op, op_class, left, right)
 
-    def visit_Div(self, node, **kwargs):
-        return lambda lhs, rhs: Div(lhs, rhs)
-
     def visit_UnaryOp(self, node, **kwargs):
         op = self.visit(node.op)
         operand = self.visit(node.operand)

pandas/core/computation/ops.py

@@ -328,31 +328,6 @@ def _not_in(x, y):
     _binary_ops_dict.update(d)
 
 
-def _cast_inplace(terms, acceptable_dtypes, dtype) -> None:
-    """
-    Cast an expression inplace.
-
-    Parameters
-    ----------
-    terms : Op
-        The expression that should cast.
-    acceptable_dtypes : list of acceptable numpy.dtype
-        Will not cast if term's dtype in this list.
-    dtype : str or numpy.dtype
-        The dtype to cast to.
-    """
-    dt = np.dtype(dtype)
-    for term in terms:
-        if term.type in acceptable_dtypes:
-            continue
-
-        try:
-            new_value = term.value.astype(dt)
-        except AttributeError:
-            new_value = dt.type(term.value)
-        term.update(new_value)
-
-
 def is_term(obj) -> bool:
     return isinstance(obj, Term)
 
@@ -509,32 +484,6 @@ def _disallow_scalar_only_bool_ops(self) -> None:
             raise NotImplementedError("cannot evaluate scalar only bool ops")
 
 
-class Div(BinOp):
-    """
-    Div operator to special case casting.
-
-    Parameters
-    ----------
-    lhs, rhs : Term or Op
-        The Terms or Ops in the ``/`` expression.
-    """
-
-    def __init__(self, lhs, rhs) -> None:
-        super().__init__("/", lhs, rhs)
-
-        if not is_numeric_dtype(lhs.return_type) or not is_numeric_dtype(
-            rhs.return_type
-        ):
-            raise TypeError(
-                f"unsupported operand type(s) for {self.op}: "
-                f"'{lhs.return_type}' and '{rhs.return_type}'"
-            )
-
-        # do not upcast float32s to float64 un-necessarily
-        acceptable_dtypes = [np.float32, np.float64]
-        _cast_inplace(com.flatten(self), acceptable_dtypes, np.float64)
-
-
 UNARY_OPS_SYMS = ("+", "-", "~", "not")
 _unary_ops_funcs = (operator.pos, operator.neg, operator.invert, operator.invert)
 _unary_ops_dict = dict(zip(UNARY_OPS_SYMS, _unary_ops_funcs))