How to run an IPython magic from a script (or timing a Python script)

Question

The IPython %timeit magic command does its job well for measuring time required to run some Python code. Now, I want to use something analogous in the Python script. I know about the timeit module, however, it has several disadvantages, for example, how to select the number of runs adaptively? i.e., the default code

import timeit t=timeit.Timer("code(f)", "from __main__ import code,f") t.timeit()  

runs the code million times. The %timeit IPyhton magic command does it automatically. I suggest that I could use something like the MATLAB code http://www.mathworks.com/matlabcentral/fileexchange/18798

that does all the job automatically (and also tells if the overhead of the function is large).

How can I call %timeit magic from a Python script (or maybe there is a better timing solution) ?

Answer 1

It depends a bit on which version of IPython you have. If you have 1.x:

from IPython import get_ipython ipython = get_ipython() 

If you have an older version:

import IPython.core.ipapi   ipython = IPython.core.ipapi.get() 

or

import IPython.ipapi   ipython = IPython.ipapi.get() 

Once that's done, run a magic command like this:

ipython.magic("timeit abs(-42)") 

Note that the script must be run via ipython.