Roy Smith <ro*@panix.com> writes:
I'm playing with the timeit module, and can't figure out how to time a
function call. I tried:
def foo ():
x = 4
return x
t = timeit.Timer ("foo()")
print t.timeit()
and quickly figured out that the environment the timed code runs under
is not what I expected:
Traceback (most recent call last):
File "./d.py", line 10, in ?
print t.timeit()
File "/usr/local/lib/python2.3/timeit.py", line 158, in timeit
return self.inner(it, self.timer)
File "<timeit-src>", line 6, in inner
NameError: global name 'foo' is not defined
In fact, trying to time "print dir()" gets you:
['_i', '_it', '_t0', '_timer']
It seems kind of surprising that I can't time functions. Am I just not
seeing something obvious?
Like the documentation for Timer? :-)
class Timer([stmt='pass' [, setup='pass' [, timer=<timer function>]]])
You can't use statements defined elsewhere, you have to define them in
the setup arguments (as a string). Like this:
define_foo = '''
def foo():
x = 4
return x
'''
t = timeit.Timer("foo()" setup=define_foo)
print t.timeit()
One common idiom I've seen is to put your definition of foo() in a
module (say x.py), then, from the command line:
$ python -m timeit -s 'from x import foo' 'foo()'
(the -m is for python 2.4 to run the timeit module; use the full path
to timeit.py instead for earlier pythons)
Alternatively, the examples for the timeit module has another way to
time functions defined in a module.
--
|>|\/|<
/--------------------------------------------------------------------------\
|David M. Cooke
|cookedm(at)physics(dot)mcmaster(dot)ca
