Command-line use

You start IPython with the command:

$ ipython [options] files

If invoked with no options, it executes all the files listed in sequence and drops you into the interpreter while still acknowledging any options you may have set in your ipythonrc file. This behavior is different from standard Python, which when called as python -i will only execute one file and ignore your configuration setup.

Please note that some of the configuration options are not available at the command line, simply because they are not practical here. Look into your ipythonrc configuration file for details on those. This file typically installed in the $HOME/.ipython directory. For Windows users, $HOME resolves to C:\\Documents and Settings\\YourUserName in most instances. In the rest of this text, we will refer to this directory as IPYTHONDIR.

Options

All options can be abbreviated to their shortest non-ambiguous form and are case-sensitive. One or two dashes can be used. Some options have an alternate short form, indicated after a |.

Most options can also be set from your ipythonrc configuration file. See the provided example for more details on what the options do. Options given at the command line override the values set in the ipythonrc file.

All options with a no| prepended can be specified in 'no' form (-nooption instead of -option) to turn the feature off.

• [-help:]print a help message and exit.
• [-no|automagic:]make magic commands automatic (without needing their first character to be @). Type @magic at the IPython prompt for more information.
• [-no|banner:]Print the initial information banner (default on).
• [-c <command>:]execute the given command string, and set sys.argv to ['c']. This is similar to the -c option in the normal Python interpreter.
• [-cache_size|cs <n>:]size of the output cache (maximum number of entries to hold in memory). The default is 1000, you can change it permanently in your config file. Setting it to 0 completely disables the caching system, and the minimum value accepted is 20 (if you provide a value less than 20, it is reset to 0 and a warning is issued) This limit is defined because otherwise you'll spend more time re-flushing a too small cache than working.
• [-classic|cl:]Gives IPython a similar feel to the classic Python prompt.
• [-colors <scheme>:]Color scheme for prompts and exception reporting. Currently implemented: NoColor, Linux and LightBG.
• [-no|color_info:]IPython can display information about objects via a set of functions, and optionally can use colors for this, syntax highlighting source code and various other elements. However, because this information is passed through a pager (like 'less') and many pagers get confused with color codes, this option is off by default. You can test it and turn it on permanently in your ipythonrc file if it works for you. As a reference, the 'less' pager supplied with Mandrake 8.2 works ok, but that in RedHat 7.2 doesn't.
• [ ]Test it and turn it on permanently if it works with your system. The magic function @color_info allows you to toggle this interactively for testing.
• [-no|debug:]Show information about the loading process. Very useful to pin down problems with your configuration files or to get details about session restores.
• [-no|deep_reload:]IPython can use the deep_reload module which reloads changes in modules recursively (it replaces the reload() function, so you don't need to change anything to use it). deep_reload() forces a full reload of modules whose code may have changed, which the default reload() function does not.
• [ ]When deep_reload is off, IPython will use the normal reload(), but deep_reload will still be available as dreload(). This feature is off by default [which means that you have both normal reload() and dreload()].
• [-editor <name>:]Which editor to use with the @edit command. By default, IPython will honor your EDITOR environment variable (if not set, vi is the Unix default and notepad the Windows one). Since this editor is invoked on the fly by IPython and is meant for editing small code snippets, you may want to use a small, lightweight editor here (in case your default EDITOR is something like Emacs).
• [-ipythondir <name>:]name of your IPython configuration directory IPYTHONDIR. This can also be specified through the environment variable IPYTHONDIR.
• [-log|l:]generate a log file of all input. Defaults to $IPYTHONDIR/log. You can use this to later restore a session by loading your logfile as a file to be executed with option -logplay (see below).
• [-logfile|lf <name>:]specify the name of your logfile.
• [-logplay|lp <name>:]you can replay a previous log. For restoring a session as close as possible to the state you left it in, use this option (don't just run the logfile). With -logplay, IPython will try to reconstruct the previous working environment in full, not just execute the commands in the logfile.
• [ ]When a session is restored, logging is automatically turned on again with the name of the logfile it was invoked with (it is read from the log header). So once you've turned logging on for a session, you can quit IPython and reload it as many times as you want and it will continue to log its history and restore from the beginning every time.
• [ ]Caveats: there are limitations in this option. The history variables _i*,_* and _dh don't get restored properly. In the future we will try to implement full session saving by writing and retrieving a 'snapshot' of the memory state of IPython. But our first attempts failed because of inherent limitations of Python's Pickle module, so this may have to wait.
• [-no|messages:]Print messages which IPython collects about its startup process (default on).
• [-no|pdb:]Automatically call the pdb debugger after every uncaught exception. If you are used to debugging using pdb, this puts you automatically inside of it after any call (either in IPython or in code called by it) which triggers an exception which goes uncaught.
• [-no|pprint:]ipython can optionally use the pprint (pretty printer) module for displaying results. pprint tends to give a nicer display of nested data structures. If you like it, you can turn it on permanently in your config file (default off).
• [-profile|p]<name>: assume that your config file is ipythonrc-<name> (looks in current dir first, then in IPYTHONDIR). This is a quick way to keep and load multiple config files for different tasks, especially if you use the include option of config files. You can keep a basic IPYTHONDIR/ipythonrc file and then have other 'profiles' which include this one and load extra things for particular tasks. For example:
• [ ]1. $HOME/.ipython/ipythonrc : load basic things you always want.
• [ ]2. $HOME/.ipython/ipythonrc-math : load (1) and basic math-related modules.
• [ ]3. $HOME/.ipython/ipythonrc-numeric : load (1) and Numeric and plotting modules.
• [ ]Since it is possible to create an endless loop by having circular file inclusions, IPython will stop if it reaches 15 recursive inclusions.
• [-prompt_in1|pi1 <string>:]Specify the string used for input prompts. Note that if you are using numbered prompts, the number is represented with a '%n' in the string. Don't forget to quote strings with spaces embedded in them. Default: 'In [%n]:'
• [-prompt_in2|pi2 <string>:]Similar to the previous option, but used for the continuation prompts. In this case, the number (%n) is replaced by as many dots as there are digits in the number (so you can have your continuation prompt aligned with your input prompt). Default: '   .%n.:' (note three spaces at the start for alignment with 'In [%n]')
• [-prompt_out|po <string>:]String used for output prompts, also uses numbers like prompt_in1. Default: 'Out[%n]:'
• [-quick:]start in bare bones mode (no config file loaded).
• [-rcfile <name>:]name of your IPython resource configuration file. Normally IPython loads ipythonrc (from current directory) or IPYTHONDIR/ipythonrc.
• [ ]If the loading of your config file fails, IPython starts with a bare bones configuration (no modules loaded at all).
• [-no|readline:]use the readline library, which is needed to support name completion and command history, among other things. It is enabled by default, but may cause problems for users of X/Emacs in Python comint or shell buffers.
• [ ]Note that X/Emacs 'eterm' buffers (opened with M-x term) support IPython's readline and syntax coloring fine, only 'emacs' (M-x shell and C-c !) buffers do not.
• [-screen_length|sl <n>:]number of lines of your screen. This is used to control printing of very long strings. Strings longer than this number of lines will be sent through a pager instead of directly printed.
• [ ]The default value for this is 0, which means IPython will auto-detect your screen size every time it needs to print certain potentially long strings (this doesn't change the behavior of the 'print' keyword, it's only triggered internally). If for some reason this isn't working well (it needs curses support), specify it yourself. Otherwise don't change the default.
• [-separate_in|si <string>:]separator before input prompts. Default: '\n'
• [-separate_out|so <string>:]separator before output prompts. Default: nothing.
• [-separate_out2|so2 <string>:]separator after output prompts. Default: nothing.
• [ ]For these three options, use the value 0 to specify no separator.
• [-nosep:]shorthand for '-SeparateIn 0 -SeparateOut 0 -SeparateOut2 0'. Simply removes all input/output separators.
• [-upgrade:]allows you to upgrade your IPYTHONDIR configuration when you install a new version of IPython. Since new versions may include new command line options or example files, this copies updated ipythonrc-type files. However, it backs up (with a .old extension) all files which it overwrites so that you can merge back any customizations you might have in your personal files.
• [-Version:]print version information and exit.
• [-xmode]<modename>: Mode for exception reporting.
• [ ]Valid modes: Plain, Context and Verbose.
• [ ]Plain: similar to python's normal traceback printing.
• [ ]Context: prints 5 lines of context source code around each line in the traceback.
• [ ]Verbose: similar to Context, but additionally prints the variables currently visible where the exception happened (shortening their strings if too long). This can potentially be very slow, if you happen to have a huge data structure whose string representation is complex to compute. Your computer may appear to freeze for a while with cpu usage at 100%. If this occurs, you can cancel the traceback with Ctrl-C (maybe hitting it more than once).