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I'm trying to capture the resulting object of IPython Notebook magic function. Specifically %timeit

So the following code...

import time def say_hello(n): time.sleep(n) print "hello" t = %timeit say_hello(5)

Prints to stdout:

1 loops, best of 3: 5 s per loop

However, I'd like to capture the result of %timeit say_hello(5) in the variable t.

A resulting object called TimeitResult is generated by %timeit, but I can't figure out how to access it from within a Notebook.

I'd like a cleaner solution than having to manually capture stdout using sys.stdout tricks (this code will be part of a presentation so I'm trying to keep it as straight forward as possible). Anyone have any ideas?

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In the source file you linked to, the docstring shows the options for running the timeit magic function; one of which is returning an object result:

-o: return a TimeitResult that can be stored in a variable to inspect the result in more details.

So, if you run

obj = %timeit -o somefunc()

obj will reference the result object that was returned (hint: use tab completion on the object, that will show you the attributes it has).

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3 Comments

Awesome, was exactly what I was looking for!
Is there any documentation of the TimeitResult object so that I don't have to use the tab completion trick and figure out all attributes myself?
Couldn't find any official docs, but the docstring in the source shows all of the attributes.
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Complementing @dsemi's answer: Use -o to save the timeit result into a variable, e.g.:

obj = %timeit -o somefunc()

The docstring documentation of the TimeitResult when using tab completion shows the available attributes:

Object returned by the timeit magic with info about the run. Contains the following attributes : loops: (int) number of loops done per measurement repeat: (int) number of times the measurement has been repeated best: (float) best execution time / number all_runs: (list of float) execution time of each run (in s) compile_time: (float) time of statement compilation (s)
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An example of consuming the TimeItResult output:

myarray = (3,2,1) sorttime = %timeit -n1 -r3 -o myarray.sort() print(sorttime.best)

Look here for the other TimeItResult attributes: https://ipython.org/ipython-doc/2/api/generated/IPython.core.magics.execution.html

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