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From: Nick Cash <nick.cash@npcinternational.com>
To: "python-list@python.org" <python-list@python.org>
Subject: RE: Does Python optimize low-power functions?
Thread-Topic: Does Python optimize low-power functions?
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Date: Fri, 6 Dec 2013 19:32:00 +0000
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Xref: csiph.com comp.lang.python:61179

>My question is, what do Python interpreters do with power operators where =
the power is a small constant, like 2?  Do they know to take the shortcut?

Nope:

Python 3.3.0 (default, Sep 25 2013, 19:28:08)=20
[GCC 4.7.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import dis
>>> dis.dis(lambda x: x*x)
  1           0 LOAD_FAST                0 (x)=20
              3 LOAD_FAST                0 (x)=20
              6 BINARY_MULTIPLY     =20
              7 RETURN_VALUE        =20
>>> dis.dis(lambda x: x**2)
  1           0 LOAD_FAST                0 (x)=20
              3 LOAD_CONST               1 (2)=20
              6 BINARY_POWER        =20
              7 RETURN_VALUE        =20


The reasons why have already been answered, I just wanted to point out that=
 Python makes it extremely easy to check these sorts of things for yourself=
.