Initiating ipython shell in terminal ipython

Initiating Jupyter notebook in terminal jupyter notebook

help(len) = len?

To get the source code len??

Both of this even works for the functions that you have created.

Tab completion is awesome. len.<tab>

Tab completion is great in conjunction with from pandas import <tab> and import <tab> to list out the objects and libraries.

* with ? for wildcard matching. *warning? and str.*find*?

ctrl + u copy from beginning, ctrl + y paste

ctrl + p previous command in history, ctrl + r history command

ctrl + l clear, ctrl + d Exit

%paste paste without indentation problem

%run test.py run a .py file in the same folder, and functions of that file is now available in the shell, and you can call them.

%timeit for single line execution, and %%timeit for multiline codes.

%magic and %lsmagic to get a list of magic functions.

Everything you input is stored in In which is a list (Input number is index number) and Everything you output is stored in Out as a dictionary (Output number is Key).

For easy access to output use print(_) , 1 underscore is the last one, 2 underscore as in print(__) for the 2nd last Out or output result.

Out[2] = _2

for not displaying an output end the statement with a semicolon. math.e;

%history -n 1-4 return history input, -n for index number, 1-4 for limiting the return statement.

shell commands work in ipython by prefixing them with ! , i.e. !ls

We can also assign variables to the output of this ipython shell commands i.e. files = !ls , which returns a special kind of list.

You can also use python variables as shell variables by using {varname} i.e. !echo {message}

You can cd by magic command %cd or simply cd . This works for every shell command.

%xmode limits the exception (/error) message. %xmode takes a single argument of the three, Plain (less information), Context (Default), and Verbose (More information). i.e. %xmode Plain .

python’s standard debugger pdb , and ipython's is ipdb . We enter into debugging with %debug . Then start giving commands ( print , type etc.) to check, and quit .

To run a file in debugging mode %run -d test.py

In the debugger help . help <specific command> .

This summary is based on the book Python Data Science Handbook by Jake VanderPlas