"""Implementation of basic magic functions. """ #----------------------------------------------------------------------------- # Copyright (c) 2012 The IPython Development Team. # # Distributed under the terms of the Modified BSD License. # # The full license is in the file COPYING.txt, distributed with this software. #----------------------------------------------------------------------------- #----------------------------------------------------------------------------- # Imports #----------------------------------------------------------------------------- from __future__ import print_function # Stdlib import io import sys from pprint import pformat # Our own packages from IPython.core.error import UsageError from IPython.core.magic import Magics, magics_class, line_magic from IPython.core.prefilter import ESC_MAGIC from IPython.utils.text import format_screen from IPython.core import magic_arguments, page from IPython.testing.skipdoctest import skip_doctest from IPython.utils.ipstruct import Struct from IPython.utils.path import unquote_filename from IPython.utils.warn import warn, error #----------------------------------------------------------------------------- # Magics class implementation #----------------------------------------------------------------------------- @magics_class class BasicMagics(Magics): """Magics that provide central IPython functionality. These are various magics that don't fit into specific categories but that are all part of the base 'IPython experience'.""" def _lsmagic(self): mesc = ESC_MAGIC cesc = mesc*2 mman = self.shell.magics_manager magics = mman.lsmagic() out = ['Available line magics:', mesc + (' '+mesc).join(magics['line']), '', 'Available cell magics:', cesc + (' '+cesc).join(magics['cell']), '', mman.auto_status()] return '\n'.join(out) @line_magic def lsmagic(self, parameter_s=''): """List currently available magic functions.""" print(self._lsmagic()) @line_magic def magic(self, parameter_s=''): """Print information about the magic function system. Supported formats: -latex, -brief, -rest """ mode = '' try: mode = parameter_s.split()[0][1:] if mode == 'rest': rest_docs = [] except IndexError: pass magic_docs = [] escapes = dict(line=ESC_MAGIC, cell=ESC_MAGIC*2) magics = self.shell.magics_manager.magics for mtype in ('line', 'cell'): escape = escapes[mtype] for fname, fn in magics[mtype].iteritems(): if mode == 'brief': # only first line if fn.__doc__: fndoc = fn.__doc__.split('\n',1)[0] else: fndoc = 'No documentation' else: if fn.__doc__: fndoc = fn.__doc__.rstrip() else: fndoc = 'No documentation' if mode == 'rest': rest_docs.append('**%s%s**::\n\n\t%s\n\n' % (escape, fname, fndoc)) else: magic_docs.append('%s%s:\n\t%s\n' % (escape, fname, fndoc)) magic_docs = ''.join(magic_docs) if mode == 'rest': return "".join(rest_docs) if mode == 'latex': print(self.format_latex(magic_docs)) return else: magic_docs = format_screen(magic_docs) if mode == 'brief': return magic_docs out = [""" IPython's 'magic' functions =========================== The magic function system provides a series of functions which allow you to control the behavior of IPython itself, plus a lot of system-type features. There are two kinds of magics, line-oriented and cell-oriented. Line magics are prefixed with the % character and work much like OS command-line calls: they get as an argument the rest of the line, where arguments are passed without parentheses or quotes. For example, this will time the given statement:: %timeit range(1000) Cell magics are prefixed with a double %%, and they are functions that get as an argument not only the rest of the line, but also the lines below it in a separate argument. These magics are called with two arguments: the rest of the call line and the body of the cell, consisting of the lines below the first. For example:: %%timeit x = numpy.random.randn((100, 100)) numpy.linalg.svd(x) will time the execution of the numpy svd routine, running the assignment of x as part of the setup phase, which is not timed. In a line-oriented client (the terminal or Qt console IPython), starting a new input with %% will automatically enter cell mode, and IPython will continue reading input until a blank line is given. In the notebook, simply type the whole cell as one entity, but keep in mind that the %% escape can only be at the very start of the cell. NOTE: If you have 'automagic' enabled (via the command line option or with the %automagic function), you don't need to type in the % explicitly for line magics; cell magics always require an explicit '%%' escape. By default, IPython ships with automagic on, so you should only rarely need the % escape. Example: typing '%cd mydir' (without the quotes) changes you working directory to 'mydir', if it exists. For a list of the available magic functions, use %lsmagic. For a description of any of them, type %magic_name?, e.g. '%cd?'. Currently the magic system has the following functions:""", magic_docs, "Summary of magic functions (from %slsmagic):", self._lsmagic(), ] page.page('\n'.join(out)) @line_magic def page(self, parameter_s=''): """Pretty print the object and display it through a pager. %page [options] OBJECT If no object is given, use _ (last output). Options: -r: page str(object), don't pretty-print it.""" # After a function contributed by Olivier Aubert, slightly modified. # Process options/args opts, args = self.parse_options(parameter_s, 'r') raw = 'r' in opts oname = args and args or '_' info = self._ofind(oname) if info['found']: txt = (raw and str or pformat)( info['obj'] ) page.page(txt) else: print('Object `%s` not found' % oname) @line_magic def profile(self, parameter_s=''): """Print your currently active IPython profile.""" from IPython.core.application import BaseIPythonApplication if BaseIPythonApplication.initialized(): print(BaseIPythonApplication.instance().profile) else: error("profile is an application-level value, but you don't appear to be in an IPython application") @line_magic def pprint(self, parameter_s=''): """Toggle pretty printing on/off.""" ptformatter = self.shell.display_formatter.formatters['text/plain'] ptformatter.pprint = bool(1 - ptformatter.pprint) print('Pretty printing has been turned', ['OFF','ON'][ptformatter.pprint]) @line_magic def colors(self, parameter_s=''): """Switch color scheme for prompts, info system and exception handlers. Currently implemented schemes: NoColor, Linux, LightBG. Color scheme names are not case-sensitive. Examples -------- To get a plain black and white terminal:: %colors nocolor """ def color_switch_err(name): warn('Error changing %s color schemes.\n%s' % (name, sys.exc_info()[1])) new_scheme = parameter_s.strip() if not new_scheme: raise UsageError( "%colors: you must specify a color scheme. See '%colors?'") return # local shortcut shell = self.shell import IPython.utils.rlineimpl as readline if not shell.colors_force and \ not readline.have_readline and sys.platform == "win32": msg = """\ Proper color support under MS Windows requires the pyreadline library. You can find it at: http://ipython.org/pyreadline.html Gary's readline needs the ctypes module, from: http://starship.python.net/crew/theller/ctypes (Note that ctypes is already part of Python versions 2.5 and newer). Defaulting color scheme to 'NoColor'""" new_scheme = 'NoColor' warn(msg) # readline option is 0 if not shell.colors_force and not shell.has_readline: new_scheme = 'NoColor' # Set prompt colors try: shell.prompt_manager.color_scheme = new_scheme except: color_switch_err('prompt') else: shell.colors = \ shell.prompt_manager.color_scheme_table.active_scheme_name # Set exception colors try: shell.InteractiveTB.set_colors(scheme = new_scheme) shell.SyntaxTB.set_colors(scheme = new_scheme) except: color_switch_err('exception') # Set info (for 'object?') colors if shell.color_info: try: shell.inspector.set_active_scheme(new_scheme) except: color_switch_err('object inspector') else: shell.inspector.set_active_scheme('NoColor') @line_magic def xmode(self, parameter_s=''): """Switch modes for the exception handlers. Valid modes: Plain, Context and Verbose. If called without arguments, acts as a toggle.""" def xmode_switch_err(name): warn('Error changing %s exception modes.\n%s' % (name,sys.exc_info()[1])) shell = self.shell new_mode = parameter_s.strip().capitalize() try: shell.InteractiveTB.set_mode(mode=new_mode) print('Exception reporting mode:',shell.InteractiveTB.mode) except: xmode_switch_err('user') @line_magic def quickref(self,arg): """ Show a quick reference sheet """ from IPython.core.usage import quick_reference qr = quick_reference + self.magic('-brief') page.page(qr) @line_magic def doctest_mode(self, parameter_s=''): """Toggle doctest mode on and off. This mode is intended to make IPython behave as much as possible like a plain Python shell, from the perspective of how its prompts, exceptions and output look. This makes it easy to copy and paste parts of a session into doctests. It does so by: - Changing the prompts to the classic ``>>>`` ones. - Changing the exception reporting mode to 'Plain'. - Disabling pretty-printing of output. Note that IPython also supports the pasting of code snippets that have leading '>>>' and '...' prompts in them. This means that you can paste doctests from files or docstrings (even if they have leading whitespace), and the code will execute correctly. You can then use '%history -t' to see the translated history; this will give you the input after removal of all the leading prompts and whitespace, which can be pasted back into an editor. With these features, you can switch into this mode easily whenever you need to do testing and changes to doctests, without having to leave your existing IPython session. """ # Shorthands shell = self.shell pm = shell.prompt_manager meta = shell.meta disp_formatter = self.shell.display_formatter ptformatter = disp_formatter.formatters['text/plain'] # dstore is a data store kept in the instance metadata bag to track any # changes we make, so we can undo them later. dstore = meta.setdefault('doctest_mode',Struct()) save_dstore = dstore.setdefault # save a few values we'll need to recover later mode = save_dstore('mode',False) save_dstore('rc_pprint',ptformatter.pprint) save_dstore('xmode',shell.InteractiveTB.mode) save_dstore('rc_separate_out',shell.separate_out) save_dstore('rc_separate_out2',shell.separate_out2) save_dstore('rc_prompts_pad_left',pm.justify) save_dstore('rc_separate_in',shell.separate_in) save_dstore('rc_plain_text_only',disp_formatter.plain_text_only) save_dstore('prompt_templates',(pm.in_template, pm.in2_template, pm.out_template)) if mode == False: # turn on pm.in_template = '>>> ' pm.in2_template = '... ' pm.out_template = '' # Prompt separators like plain python shell.separate_in = '' shell.separate_out = '' shell.separate_out2 = '' pm.justify = False ptformatter.pprint = False disp_formatter.plain_text_only = True shell.magic('xmode Plain') else: # turn off pm.in_template, pm.in2_template, pm.out_template = dstore.prompt_templates shell.separate_in = dstore.rc_separate_in shell.separate_out = dstore.rc_separate_out shell.separate_out2 = dstore.rc_separate_out2 pm.justify = dstore.rc_prompts_pad_left ptformatter.pprint = dstore.rc_pprint disp_formatter.plain_text_only = dstore.rc_plain_text_only shell.magic('xmode ' + dstore.xmode) # Store new mode and inform dstore.mode = bool(1-int(mode)) mode_label = ['OFF','ON'][dstore.mode] print('Doctest mode is:', mode_label) @line_magic def gui(self, parameter_s=''): """Enable or disable IPython GUI event loop integration. %gui [GUINAME] This magic replaces IPython's threaded shells that were activated using the (pylab/wthread/etc.) command line flags. GUI toolkits can now be enabled at runtime and keyboard interrupts should work without any problems. The following toolkits are supported: wxPython, PyQt4, PyGTK, Tk and Cocoa (OSX):: %gui wx # enable wxPython event loop integration %gui qt4|qt # enable PyQt4 event loop integration %gui gtk # enable PyGTK event loop integration %gui gtk3 # enable Gtk3 event loop integration %gui tk # enable Tk event loop integration %gui OSX # enable Cocoa event loop integration # (requires %matplotlib 1.1) %gui # disable all event loop integration WARNING: after any of these has been called you can simply create an application object, but DO NOT start the event loop yourself, as we have already handled that. """ opts, arg = self.parse_options(parameter_s, '') if arg=='': arg = None try: return self.shell.enable_gui(arg) except Exception as e: # print simple error message, rather than traceback if we can't # hook up the GUI error(str(e)) @skip_doctest @line_magic def precision(self, s=''): """Set floating point precision for pretty printing. Can set either integer precision or a format string. If numpy has been imported and precision is an int, numpy display precision will also be set, via ``numpy.set_printoptions``. If no argument is given, defaults will be restored. Examples -------- :: In [1]: from math import pi In [2]: %precision 3 Out[2]: u'%.3f' In [3]: pi Out[3]: 3.142 In [4]: %precision %i Out[4]: u'%i' In [5]: pi Out[5]: 3 In [6]: %precision %e Out[6]: u'%e' In [7]: pi**10 Out[7]: 9.364805e+04 In [8]: %precision Out[8]: u'%r' In [9]: pi**10 Out[9]: 93648.047476082982 """ ptformatter = self.shell.display_formatter.formatters['text/plain'] ptformatter.float_precision = s return ptformatter.float_format @magic_arguments.magic_arguments() @magic_arguments.argument( '-e', '--export', action='store_true', default=False, help='Export IPython history as a notebook. The filename argument ' 'is used to specify the notebook name and format. For example ' 'a filename of notebook.ipynb will result in a notebook name ' 'of "notebook" and a format of "xml". Likewise using a ".json" ' 'or ".py" file extension will write the notebook in the json ' 'or py formats.' ) @magic_arguments.argument( '-f', '--format', help='Convert an existing IPython notebook to a new format. This option ' 'specifies the new format and can have the values: xml, json, py. ' 'The target filename is chosen automatically based on the new ' 'format. The filename argument gives the name of the source file.' ) @magic_arguments.argument( 'filename', type=unicode, help='Notebook name or filename' ) @line_magic def notebook(self, s): """Export and convert IPython notebooks. This function can export the current IPython history to a notebook file or can convert an existing notebook file into a different format. For example, to export the history to "foo.ipynb" do "%notebook -e foo.ipynb". To export the history to "foo.py" do "%notebook -e foo.py". To convert "foo.ipynb" to "foo.json" do "%notebook -f json foo.ipynb". Possible formats include (json/ipynb, py). """ args = magic_arguments.parse_argstring(self.notebook, s) from IPython.nbformat import current args.filename = unquote_filename(args.filename) if args.export: fname, name, format = current.parse_filename(args.filename) cells = [] hist = list(self.shell.history_manager.get_range()) for session, prompt_number, input in hist[:-1]: cells.append(current.new_code_cell(prompt_number=prompt_number, input=input)) worksheet = current.new_worksheet(cells=cells) nb = current.new_notebook(name=name,worksheets=[worksheet]) with io.open(fname, 'w', encoding='utf-8') as f: current.write(nb, f, format); elif args.format is not None: old_fname, old_name, old_format = current.parse_filename(args.filename) new_format = args.format if new_format == u'xml': raise ValueError('Notebooks cannot be written as xml.') elif new_format == u'ipynb' or new_format == u'json': new_fname = old_name + u'.ipynb' new_format = u'json' elif new_format == u'py': new_fname = old_name + u'.py' else: raise ValueError('Invalid notebook format: %s' % new_format) with io.open(old_fname, 'r', encoding='utf-8') as f: nb = current.read(f, old_format) with io.open(new_fname, 'w', encoding='utf-8') as f: current.write(nb, f, new_format)