Replace all import of IPython.utils.warn module
Replace all import of IPython.utils.warn module

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"""Implementation of basic magic functions."""
from __future__ import print_function
import io
import sys
from pprint import pformat
from IPython.core import magic_arguments, page
from IPython.core.error import UsageError
from IPython.core.magic import Magics, magics_class, line_magic, magic_escapes
from IPython.utils.text import format_screen, dedent, indent
from IPython.testing.skipdoctest import skip_doctest
from IPython.utils.ipstruct import Struct
from IPython.utils.path import unquote_filename
from IPython.utils.py3compat import unicode_type
from warnings import warn
from logging import error
class MagicsDisplay(object):
def __init__(self, magics_manager):
self.magics_manager = magics_manager
def _lsmagic(self):
"""The main implementation of the %lsmagic"""
mesc = magic_escapes['line']
cesc = magic_escapes['cell']
mman = self.magics_manager
magics = mman.lsmagic()
out = ['Available line magics:',
mesc + (' '+mesc).join(sorted(magics['line'])),
'Available cell magics:',
cesc + (' '+cesc).join(sorted(magics['cell'])),
return '\n'.join(out)
def _repr_pretty_(self, p, cycle):
def __str__(self):
return self._lsmagic()
def _jsonable(self):
"""turn magics dict into jsonable dict of the same structure
replaces object instances with their class names as strings
magic_dict = {}
mman = self.magics_manager
magics = mman.lsmagic()
for key, subdict in magics.items():
d = {}
magic_dict[key] = d
for name, obj in subdict.items():
classname = obj.__self__.__class__.__name__
except AttributeError:
classname = 'Other'
d[name] = classname
return magic_dict
def _repr_json_(self):
return self._jsonable()
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'."""
'-l', '--line', action='store_true',
help="""Create a line magic alias."""
'-c', '--cell', action='store_true',
help="""Create a cell magic alias."""
help="""Name of the magic to be created."""
help="""Name of the existing line or cell magic."""
def alias_magic(self, line=''):
"""Create an alias for an existing line or cell magic.
In [1]: %alias_magic t timeit
Created `%t` as an alias for `%timeit`.
Created `%%t` as an alias for `%%timeit`.
In [2]: %t -n1 pass
1 loops, best of 3: 954 ns per loop
In [3]: %%t -n1
...: pass
1 loops, best of 3: 954 ns per loop
In [4]: %alias_magic --cell whereami pwd
UsageError: Cell magic function `%%pwd` not found.
In [5]: %alias_magic --line whereami pwd
Created `%whereami` as an alias for `%pwd`.
In [6]: %whereami
Out[6]: u'/home/testuser'
args = magic_arguments.parse_argstring(self.alias_magic, line)
shell =
mman =
escs = ''.join(magic_escapes.values())
target =
name =
# Find the requested magics.
m_line = shell.find_magic(target, 'line')
m_cell = shell.find_magic(target, 'cell')
if args.line and m_line is None:
raise UsageError('Line magic function `%s%s` not found.' %
(magic_escapes['line'], target))
if args.cell and m_cell is None:
raise UsageError('Cell magic function `%s%s` not found.' %
(magic_escapes['cell'], target))
# If --line and --cell are not specified, default to the ones
# that are available.
if not args.line and not args.cell:
if not m_line and not m_cell:
raise UsageError(
'No line or cell magic with name `%s` found.' % target
args.line = bool(m_line)
args.cell = bool(m_cell)
if args.line:
mman.register_alias(name, target, 'line')
print('Created `%s%s` as an alias for `%s%s`.' % (
magic_escapes['line'], name,
magic_escapes['line'], target))
if args.cell:
mman.register_alias(name, target, 'cell')
print('Created `%s%s` as an alias for `%s%s`.' % (
magic_escapes['cell'], name,
magic_escapes['cell'], target))
def lsmagic(self, parameter_s=''):
"""List currently available magic functions."""
return MagicsDisplay(
def _magic_docs(self, brief=False, rest=False):
"""Return docstrings from magic functions."""
mman =
docs = mman.lsmagic_docs(brief, missing='No documentation')
if rest:
format_string = '**%s%s**::\n\n%s\n\n'
format_string = '%s%s:\n%s\n'
return ''.join(
[format_string % (magic_escapes['line'], fname,
for fname, fndoc in sorted(docs['line'].items())]
[format_string % (magic_escapes['cell'], fname,
for fname, fndoc in sorted(docs['cell'].items())]
def magic(self, parameter_s=''):
"""Print information about the magic function system.
Supported formats: -latex, -brief, -rest
mode = ''
mode = parameter_s.split()[0][1:]
except IndexError:
brief = (mode == 'brief')
rest = (mode == 'rest')
magic_docs = self._magic_docs(brief, rest)
if mode == 'latex':
magic_docs = format_screen(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))
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 your 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:""",
"Summary of magic functions (from %slsmagic):" % magic_escapes['line'],
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).
-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 =
if info['found']:
txt = (raw and str or pformat)( info['obj'] )
print('Object `%s` not found' % oname)
def profile(self, parameter_s=''):
"""Print your currently active IPython profile.
See Also
prun : run code using the Python profiler
warn("%profile is now deprecated. Please use get_ipython().profile instead.")
from IPython.core.application import BaseIPythonApplication
if BaseIPythonApplication.initialized():
error("profile is an application-level value, but you don't appear to be in an IPython application")
def pprint(self, parameter_s=''):
"""Toggle pretty printing on/off."""
ptformatter =['text/plain']
ptformatter.pprint = bool(1 - ptformatter.pprint)
print('Pretty printing has been turned',
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.
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?'")
# local shortcut
shell =
if not shell.colors_force:
if sys.platform in {'win32', 'cli'}:
import IPython.utils.rlineimpl as readline
if not readline.have_readline:
msg = """\
Proper color support under MS Windows requires the pyreadline library.
You can find it at:
Defaulting color scheme to 'NoColor'"""
new_scheme = 'NoColor'
elif not shell.has_readline:
# Coloured prompts get messed up without readline
# Will remove this check after switching to prompt_toolkit
new_scheme = 'NoColor'
# Set prompt colors
shell.prompt_manager.color_scheme = new_scheme
shell.colors = \
# Set exception colors
shell.InteractiveTB.set_colors(scheme = new_scheme)
shell.SyntaxTB.set_colors(scheme = new_scheme)
# Set info (for 'object?') colors
if shell.color_info:
color_switch_err('object inspector')
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' %
shell =
new_mode = parameter_s.strip().capitalize()
print('Exception reporting mode:',shell.InteractiveTB.mode)
def quickref(self,arg):
""" Show a quick reference sheet """
from IPython.core.usage import quick_reference
qr = quick_reference + self._magic_docs(brief=True)
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 =
pm = shell.prompt_manager
meta = shell.meta
disp_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('prompt_templates',(pm.in_template, pm.in2_template, pm.out_template))
if not mode:
# 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.active_types = ['text/plain']
shell.magic('xmode Plain')
# 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.active_types = dstore.rc_active_types
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)
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 qt5 # enable PyQt5 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
except Exception as e:
# print simple error message, rather than traceback if we can't
# hook up the GUI
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.
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 =['text/plain']
ptformatter.float_precision = s
return ptformatter.float_format
'-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 "json". Likewise using a ".py" '
'file extension will write the notebook as a Python script'
'filename', type=unicode_type,
help='Notebook name or filename'
def notebook(self, s):
"""Export and convert IPython notebooks.
This function can export the current IPython history to a notebook file.
For example, to export the history to "foo.ipynb" do "%notebook -e foo.ipynb".
To export the history to "" do "%notebook -e".
args = magic_arguments.parse_argstring(self.notebook, s)
from nbformat import write, v4
args.filename = unquote_filename(args.filename)
if args.export:
cells = []
hist = list(
raise ValueError('History is empty, cannot export')
for session, execution_count, source in hist[:-1]:
nb = v4.new_notebook(cells=cells)
with, 'w', encoding='utf-8') as f:
write(nb, f, version=4)