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Jupyter Notebooks Cheat Sheet
MAGIC COMMANDS
%quickref Display the IPython Quick Reference Card
%magic Display detailed documentation for all of the available magic commands
%debug Enter the interactive debugger at the bottom of the last exception trace-back
%hist Print command input (and optionally output) history
%pdb Automatically enter debugger after any exception
%paste Execute pre-formatted Python code from clipboard
%cpaste Open a special prompt for manually pasting Python code to be executed
%reset Delete all variables / names defined in interactive namespace
%page OBJECT Pretty print the object and display it through a pager
%run script.py Run a Python script inside IPython
%prun statement Execute statement with cProfile and report the profiler output
%time statement Report the execution time of single statement
%timeit statement Run a statement multiple times to compute an ensemble average execution time. Useful for timing code with very short execution time
%who, %who_ls, %whos Display variables defined in interactive namespace, with varying levels of information / verbosity
%xdel variable Delete a variable and attempt to clear any references to the object in the IPython internals
INTERACTING WITH THE OPERATING SYSTEM
!cmd Execute cmd in the system shell
output = !cmd args Run cmd and store the stdout in output
%alias alias_name cmd Define an alias for a system (shell) command
%bookmark Utilize IPython's directory bookmarking system
%cd directory Change system working directory to passed directory
%pwd Return the current system working directory
%pushd directory Place current directory on stack and change to target directory
%popd Change to directory popped off the top of the stack
%dirs Return a list containing the current directory stack
%dhist Print the history of visited directories
%env Return the system environment variables as a dict
Input variables are stored in variables named like iX, where X is the input line number
IPython is capable of logging the entire console session including input and output
Logging is turned on by typing %logstart
Starting a line in IPython with an exclamation point !, or bang, tells IPython to execute everything after the bang in the system shell
The console output of a shell command can be stored in a variable by assigning the !-escaped expression to a variable
TIMING CODE
%time runs a statement once, reporting the total execution time
%timeit given an arbitrary statement, it has a heuristic to run a statement multiple times to produce a fairly accurate average runtime