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       ipython - An Enhanced Interactive Python


       ipython [options] files...


       An  interactive Python shell with automatic history (input and output),
       dynamic object introspection, easier configuration, command completion,
       access  to  the system shell, integration with numerical and scientific
       computing tools, and more.


       The following special options are ONLY valid at the  beginning  of  the
       command  line,  and  not  later.   This  is  because  they  control the
       initialization of ipython itself,  before  the  normal  option-handling
       mechanism is active.

       -gthread, -qthread, -q4thread, -wthread, -pylab
              Only  ONE of these can be given, and it can only be given as the
              first option passed to IPython (it will have no  effect  in  any
              other  position).   They  provide threading support for the GTK,
              QT3, QT4 and WXWidgets toolkits, for the matplotlib library  and
              Twisted reactor.

              With  any  of  the  first four options, IPython starts running a
              separate thread for the graphical toolkit’s operation,  so  that
              you  can  open  and  control  graphical  elements from within an
              IPython  command  line,  without  blocking.   All  four  provide
              essentially  the  same functionality, respectively for GTK, QT3,
              QT4 and WXWidgets (via their Python interfaces).

              Note that with -wthread, you can additionally use the -wxversion
              option  to  request  a  specific version of wx to be used.  This
              requires that you have the wxversion  Python  module  installed,
              which is part of recent wxPython distributions.

              If  -pylab  is  given,  IPython  loads  special  support for the
              matplotlib library (, allowing
              interactive  usage  of  any  of  its  backends as defined in the
              user’s .matplotlibrc file.  It automatically activates  GTK,  QT
              or  WX threading for IPyhton if the choice of matplotlib backend
              requires it.  It also modifies the  %run  command  to  correctly
              execute  (without  blocking)  any  matplotlib-based script which
              calls show() at the end.

       -tk    The  -g/q/q4/wthread  options,  and  -pylab  (if  matplotlib  is
              configured  to  use  GTK,  QT  or  WX),  will  normally block Tk
              graphical interfaces.  This  means  that  when  GTK,  QT  or  WX
              threading is active, any attempt to open a Tk GUI will result in
              a dead window, and possibly  cause  the  Python  interpreter  to
              crash.   An  extra  option,  -tk,  is  available to address this
              issue.  It can ONLY be given as a SECOND option after any of the
              above (-gthread, -qthread, -wthread or -pylab).

              If  -tk  is  given,  IPython will try to coordinate Tk threading
              with GTK, QT or WX.  This is however potentially unreliable, and
              you  will have to test on your platform and Python configuration
              to determine whether  it  works  for  you.   Debian  users  have
              reported  success, apparently due to the fact that Debian builds
              all of Tcl, Tk, Tkinter and Python with pthreads support.  Under
              other  Linux  environments  (such as Fedora Core 2), this option
              has caused random crashes and lockups of the Python interpreter.
              Under other operating systems (Mac OSX and Windows), you’ll need
              to try it to find out,  since  currently  no  user  reports  are

              There  is  unfortunately  no  way  for  IPython  to determine at
              runtime whether -tk will work reliably or not, so you will  need
              to do some experiments before relying on it for regular work.


       After  the above threading options have been given, regular options can
       follow in any order.  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  examples  for  assistance.   Options  given  on  the
       commandline override the values set in the ipythonrc file.

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

       -h, --help
              Show summary of options.

       -autocall <val>
              Make IPython automatically call any callable object even if  you
              didn’t  type explicit parentheses. For example, ’str 43’ becomes
              str(43) automatically.  The value can  be  ’0’  to  disable  the
              feature,  ’1’  for  ’smart’ autocall, where it is not applied if
              there are no more arguments on the  line,  and  ’2’  for  ’full’
              autocall,  where  all  callable objects are automatically called
              (even if no arguments are present).  The default is ’1’.

              Turn automatic indentation on/off.

              Make magic  commands  automatic  (without  needing  their  first
              character  to be %).  Type %magic at the IPython prompt for more

              When a syntax error occurs after editing a  file,  automatically
              open the file to the trouble causing line for convenient fixing.

              Print the intial 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

       -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.

              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.

              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.

              Set  to  confirm  when  you  try  to  exit  IPython  with an EOF
              (Control-D in Unix, Control-Z/Enter in Windows). Note that using
              the  magic functions @Exit or @Quit you can force a direct exit,
              bypassing any confirmation.

              Show information about the loading process. Very useful  to  pin
              down  problems  with  your configuration files or to get details
              about session restores.

              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>
              The name of your  IPython  configuration  directory  IPYTHONDIR.
              This  can  also  be  specified  through the environment variable

       -log|l Generate  a  log  file  of  all  input.  The   file   is   named
      in  your  current directory (which prevents logs
              from multiple IPython sessions from trampling each  other).  You
              can  use this to later restore a session by loading your logfile
              as a file to be executed with option -logplay (see below).

              Specify the name of your logfile.

              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.

              Print messages which IPython collects about its startup  process
              (default on).

              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

       -pydb  Makes  IPython  use  the third party "pydb" package as debugger,
              instead of pdb. Requires that pydb is installed.

              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 ’\#’ in
              the string. Don’t forget to quote strings with  spaces  embedded
              in them. Default: ’In [\#]: ’.

              Most  bash-like  escapes  can  be  used  to  customize IPython’s
              prompts, as well as a few additional  ones  which  are  IPython-
              specific.   All  valid prompt escapes are described in detail in
              the Customization section of the IPython HTML/PDF manual.

       -prompt_in2|pi2 <string>
              Similar to the previous option, but used  for  the  continuation
              prompts.  The special sequence ’\D’ is similar to ’\#’, but with
              all digits replaced dots (so  you  can  have  your  continuation
              prompt  aligned  with  your  input prompt). Default: ’   .\D.: ’
              (note three spaces at the start for alignment with ’In [\#]’).

       -prompt_out|po <string>
              String  used  for  output  prompts,  also  uses   numbers   like
              prompt_in1.  Default: ’Out[\#]:’.

       -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).

              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 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

              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 ’0.

       -separate_out|so <string>
              Separator before output prompts.  Default: 0 (nothing).

       -separate_out2|so2 <string>
              Separator after output prompts.  Default: 0 (nothing).

       -nosep Shorthand for ’-separate_in 0 -separate_out 0 -separate_out2 0’.
              Simply removes all input/output separators.

              Allows  you  to  upgrade  your IPYTHONDIR configuration when you
              install a new  version  of  IPython.   Since  new  versions  may
              include  new command lines 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 custimizations you might have in your personal files.

              Print version information and exit.

       -wxversion <string>
              Select a specific version of wxPython (used in conjunction  with
              -wthread).   Requires  the  wxversion  module,  part  of  recent
              wxPython distributions.

       -xmode <modename>
              Mode for  exception  reporting.   The  valid  modes  are  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).


       It  is  possible  to  start  an IPython instance inside your own Python
       programs.   In  the  documentation  example  files   there   are   some
       illustrations on how to do this.

       This  feature  allows  you  to  evalutate dynamically the state of your
       code, operate with your variables, analyze  them,  etc.   Note  however
       that any changes you make to values while in the shell do NOT propagate
       back to the running code, so it is safe to modify your  values  because
       you won’t break your code in bizarre ways by doing so.


       IPython  was  written by Fernando Perez <>, based on
       earlier  code  by  Janko  Hauser  <>  and  Nathaniel  Gray
       <>.   This  manual  page  was written by Jack Moffitt
       <>, for the Debian project (but may be used by others).

                               November 30, 2004                    IPYTHON(1)