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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"

"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<head>

<title>matplotlib.cbook — Matplotlib 3.2.0 documentation</title>

title="Search within Matplotlib 3.2.0 documentation"

href="../../_static/opensearch.xml"/>

</head><body>

<div id="unreleased-message"> You are reading an old version of the documentation (v3.2.0). For the latest version see <a href="/stable/">https://matplotlib.org/stable/</a> </div>

<div style="float: left; position: absolute; width: 496px; bottom: 0; padding-bottom: 24px">Version 3.2.0</div>

<div id="forkongithub"><a href="https://github.com/matplotlib/matplotlib">Fork me on GitHub</a></div>

</div>

<ul>

<li><a href="../../users/installing.html">Installation</a></li>

<li><a href="../../contents.html">Documentation</a></li>

<li><a href="../../gallery/index.html">Examples</a></li>

<li><a href="../../tutorials/index.html">Tutorials</a></li>

<li><a href="../../devel/index.html">Contributing</a></li>

</form>

</li>

</ul>

</nav>

<h3>Navigation</h3>

<ul>

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accesskey="I">index</a></li>

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>modules</a> |</li>

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<li class="nav-item nav-item-1"><a href="../index.html" >Module code</a> »</li>

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<h3>Related Topics</h3>

<ul>

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</ul>

</div>

<h1>Source code for matplotlib.cbook</h1><div class="highlight"><pre>

"""

A collection of utility functions and classes. Originally, many

(but not all) were from the Python Cookbook -- hence the name cbook.

This module is safe to import from anywhere within matplotlib;

it imports matplotlib only at runtime.

"""

import collections

import collections.abc

import contextlib

import functools

import glob

import gzip

import itertools

import locale

import numbers

import operator

import os

from pathlib import Path

import re

import shlex

import subprocess

import sys

import time

import traceback

import types

import warnings

import weakref

from weakref import WeakMethod

import numpy as np

import matplotlib

from .deprecation import (

deprecated, warn_deprecated,

_rename_parameter, _delete_parameter, _make_keyword_only,

_suppress_matplotlib_deprecation_warning,

MatplotlibDeprecationWarning, mplDeprecation)

def _exception_printer(exc):

traceback.print_exc()

class _StrongRef:

"""

Wrapper similar to a weakref, but keeping a strong reference to the object.

"""

def __init__(self, obj):

self._obj = obj

def __call__(self):

return self._obj

def __eq__(self, other):

return isinstance(other, _StrongRef) and self._obj == other._obj

def __hash__(self):

return hash(self._obj)

<div class="viewcode-block" id="CallbackRegistry"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.CallbackRegistry">[docs]</a>class CallbackRegistry:

"""Handle registering and disconnecting for a set of signals and callbacks:

>>> def oneat(x):

... print('eat', x)

>>> def ondrink(x):

... print('drink', x)

>>> from matplotlib.cbook import CallbackRegistry

>>> callbacks = CallbackRegistry()

>>> id_eat = callbacks.connect('eat', oneat)

>>> id_drink = callbacks.connect('drink', ondrink)

>>> callbacks.process('drink', 123)

drink 123

>>> callbacks.process('eat', 456)

eat 456

>>> callbacks.process('be merry', 456) # nothing will be called

>>> callbacks.disconnect(id_eat)

>>> callbacks.process('eat', 456) # nothing will be called

In practice, one should always disconnect all callbacks when they are

no longer needed to avoid dangling references (and thus memory leaks).

However, real code in Matplotlib rarely does so, and due to its design,

it is rather difficult to place this kind of code. To get around this,

and prevent this class of memory leaks, we instead store weak references

to bound methods only, so when the destination object needs to die, the

CallbackRegistry won't keep it alive.

Parameters

----------

exception_handler : callable, optional

If provided must have signature ::

def handler(exc: Exception) -> None:

If not None this function will be called with any `Exception`

subclass raised by the callbacks in `CallbackRegistry.process`.

The handler may either consume the exception or re-raise.

The callable must be pickle-able.

The default handler is ::

def h(exc):

traceback.print_exc()

"""

# We maintain two mappings:

# callbacks: signal -> {cid -> callback}

# _func_cid_map: signal -> {callback -> cid}

# (actually, callbacks are weakrefs to the actual callbacks).

def __init__(self, exception_handler=_exception_printer):

self.exception_handler = exception_handler

self.callbacks = {}

self._cid_gen = itertools.count()

self._func_cid_map = {}

# In general, callbacks may not be pickled; thus, we simply recreate an

# empty dictionary at unpickling. In order to ensure that `__setstate__`

# (which just defers to `__init__`) is called, `__getstate__` must

# return a truthy value (for pickle protocol>=3, i.e. Py3, the

# *actual* behavior is that `__setstate__` will be called as long as

# `__getstate__` does not return `None`, but this is undocumented -- see

# http://bugs.python.org/issue12290).

def __getstate__(self):

return {'exception_handler': self.exception_handler}

def __setstate__(self, state):

self.__init__(**state)

<div class="viewcode-block" id="CallbackRegistry.connect"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.CallbackRegistry.connect">[docs]</a> def connect(self, s, func):

"""Register *func* to be called when signal *s* is generated.

"""

self._func_cid_map.setdefault(s, {})

try:

proxy = WeakMethod(func, self._remove_proxy)

except TypeError:

proxy = _StrongRef(func)

if proxy in self._func_cid_map[s]:

return self._func_cid_map[s][proxy]

cid = next(self._cid_gen)

self._func_cid_map[s][proxy] = cid

self.callbacks.setdefault(s, {})

self.callbacks[s][cid] = proxy

return cid</div>

# Keep a reference to sys.is_finalizing, as sys may have been cleared out

# at that point.

def _remove_proxy(self, proxy, *, _is_finalizing=sys.is_finalizing):

if _is_finalizing():

# Weakrefs can't be properly torn down at that point anymore.

return

for signal, proxies in list(self._func_cid_map.items()):

try:

del self.callbacks[signal][proxies[proxy]]

except KeyError:

pass

if len(self.callbacks[signal]) == 0:

del self.callbacks[signal]

del self._func_cid_map[signal]

<div class="viewcode-block" id="CallbackRegistry.disconnect"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.CallbackRegistry.disconnect">[docs]</a> def disconnect(self, cid):

"""Disconnect the callback registered with callback id *cid*.

"""

for eventname, callbackd in list(self.callbacks.items()):

try:

del callbackd[cid]

except KeyError:

continue

else:

for signal, functions in list(self._func_cid_map.items()):

for function, value in list(functions.items()):

if value == cid:

del functions[function]

return</div>

<div class="viewcode-block" id="CallbackRegistry.process"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.CallbackRegistry.process">[docs]</a> def process(self, s, *args, **kwargs):

"""

Process signal *s*.

All of the functions registered to receive callbacks on *s* will be

called with ``*args`` and ``**kwargs``.

"""

for cid, ref in list(self.callbacks.get(s, {}).items()):

func = ref()

if func is not None:

try:

func(*args, **kwargs)

# this does not capture KeyboardInterrupt, SystemExit,

# and GeneratorExit

except Exception as exc:

if self.exception_handler is not None:

self.exception_handler(exc)

else:

raise</div></div>

<div class="viewcode-block" id="silent_list"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.silent_list">[docs]</a>class silent_list(list):

"""

A list with a short ``repr()``.

This is meant to be used for a homogeneous list of artists, so that they

don't cause long, meaningless output.

Instead of ::

[<matplotlib.lines.Line2D object at 0x7f5749fed3c8>,

<matplotlib.lines.Line2D object at 0x7f5749fed4e0>,

<matplotlib.lines.Line2D object at 0x7f5758016550>]

one will get ::

"""

def __init__(self, type, seq=None):

self.type = type

if seq is not None:

self.extend(seq)

def __repr__(self):

return '<a list of %d %s objects>' % (len(self), self.type)

__str__ = __repr__

def __getstate__(self):

# store a dictionary of this SilentList's state

return {'type': self.type, 'seq': self[:]}

def __setstate__(self, state):

self.type = state['type']

self.extend(state['seq'])</div>

<div class="viewcode-block" id="IgnoredKeywordWarning"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.IgnoredKeywordWarning">[docs]</a>class IgnoredKeywordWarning(UserWarning):

"""

A class for issuing warnings about keyword arguments that will be ignored

by Matplotlib.

"""

pass</div>

<div class="viewcode-block" id="local_over_kwdict"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.local_over_kwdict">[docs]</a>def local_over_kwdict(local_var, kwargs, *keys):

"""

Enforces the priority of a local variable over potentially conflicting

argument(s) from a kwargs dict. The following possible output values are

considered in order of priority::

local_var > kwargs[keys[0]] > ... > kwargs[keys[-1]]

The first of these whose value is not None will be returned. If all are

None then None will be returned. Each key in keys will be removed from the

kwargs dict in place.

Parameters

----------

local_var : any object

The local variable (highest priority).

kwargs : dict

Dictionary of keyword arguments; modified in place.

keys : str(s)

Name(s) of keyword arguments to process, in descending order of

priority.

Returns

-------

out : any object

Either local_var or one of kwargs[key] for key in keys.

Raises

------

IgnoredKeywordWarning

For each key in keys that is removed from kwargs but not used as

the output value.

"""

out = local_var

for key in keys:

kwarg_val = kwargs.pop(key, None)

if kwarg_val is not None:

if out is None:

out = kwarg_val

else:

_warn_external('"%s" keyword argument will be ignored' % key,

IgnoredKeywordWarning)

return out</div>

<div class="viewcode-block" id="strip_math"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.strip_math">[docs]</a>def strip_math(s):

"""

Remove latex formatting from mathtext.

Only handles fully math and fully non-math strings.

"""

if len(s) >= 2 and s[0] == s[-1] == "$":

s = s[1:-1]

for tex, plain in [

(r"\times", "x"), # Specifically for Formatter support.

(r"\mathdefault", ""),

(r"\rm", ""),

(r"\cal", ""),

(r"\tt", ""),

(r"\it", ""),

("\\", ""),

("{", ""),

("}", ""),

]:

s = s.replace(tex, plain)

return s</div>

<div class="viewcode-block" id="iterable"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.iterable">[docs]</a>@deprecated('3.1', alternative='np.iterable')

def iterable(obj):

"""return true if *obj* is iterable"""

try:

iter(obj)

except TypeError:

return False

return True</div>

<div class="viewcode-block" id="is_hashable"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.is_hashable">[docs]</a>@deprecated("3.1", alternative="isinstance(..., collections.abc.Hashable)")

def is_hashable(obj):

"""Returns true if *obj* can be hashed"""

try:

hash(obj)

except TypeError:

return False

return True</div>

<div class="viewcode-block" id="is_writable_file_like"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.is_writable_file_like">[docs]</a>def is_writable_file_like(obj):

"""Return whether *obj* looks like a file object with a *write* method."""

return callable(getattr(obj, 'write', None))</div>

<div class="viewcode-block" id="file_requires_unicode"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.file_requires_unicode">[docs]</a>def file_requires_unicode(x):

"""

Return whether the given writable file-like object requires Unicode to be

written to it.

"""

try:

x.write(b'')

except TypeError:

return True

else:

return False</div>

<div class="viewcode-block" id="to_filehandle"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.to_filehandle">[docs]</a>def to_filehandle(fname, flag='r', return_opened=False, encoding=None):

"""

Convert a path to an open file handle or pass-through a file-like object.

Consider using `open_file_cm` instead, as it allows one to properly close

newly created file objects more easily.

Parameters

----------

fname : str or path-like or file-like object

If `str` or `os.PathLike`, the file is opened using the flags specified

by *flag* and *encoding*. If a file-like object, it is passed through.

flag : str, default 'r'

Passed as the *mode* argument to `open` when *fname* is `str` or

`os.PathLike`; ignored if *fname* is file-like.

return_opened : bool, default False

If True, return both the file object and a boolean indicating whether

this was a new file (that the caller needs to close). If False, return

only the new file.

encoding : str or None, default None

Passed as the *mode* argument to `open` when *fname* is `str` or

`os.PathLike`; ignored if *fname* is file-like.

Returns

-------

fh : file-like

opened : bool

*opened* is only returned if *return_opened* is True.

"""

if isinstance(fname, os.PathLike):

fname = os.fspath(fname)

if isinstance(fname, str):

if fname.endswith('.gz'):

# get rid of 'U' in flag for gzipped files.

flag = flag.replace('U', '')

fh = gzip.open(fname, flag)

elif fname.endswith('.bz2'):

# python may not be complied with bz2 support,

# bury import until we need it

import bz2

# get rid of 'U' in flag for bz2 files

fh = bz2.BZ2File(fname, flag)

else:

fh = open(fname, flag, encoding=encoding)

opened = True

elif hasattr(fname, 'seek'):

fh = fname

opened = False

else:

raise ValueError('fname must be a PathLike or file handle')

if return_opened:

return fh, opened

return fh</div>

<div class="viewcode-block" id="open_file_cm"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.open_file_cm">[docs]</a>@contextlib.contextmanager

def open_file_cm(path_or_file, mode="r", encoding=None):

r"""Pass through file objects and context-manage `.PathLike`\s."""

fh, opened = to_filehandle(path_or_file, mode, True, encoding)

if opened:

with fh:

yield fh

else:

yield fh</div>

<div class="viewcode-block" id="is_scalar_or_string"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.is_scalar_or_string">[docs]</a>def is_scalar_or_string(val):

"""Return whether the given object is a scalar or string like."""

return isinstance(val, str) or not np.iterable(val)</div>

<div class="viewcode-block" id="get_sample_data"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.get_sample_data">[docs]</a>def get_sample_data(fname, asfileobj=True):

"""

Return a sample data file. *fname* is a path relative to the

`mpl-data/sample_data` directory. If *asfileobj* is `True`

return a file object, otherwise just a file path.

Sample data files are stored in the 'mpl-data/sample_data' directory within

the Matplotlib package.

If the filename ends in .gz, the file is implicitly ungzipped.

"""

path = Path(matplotlib._get_data_path(), 'sample_data', fname)

if asfileobj:

suffix = path.suffix.lower()

if suffix == '.gz':

return gzip.open(path)

elif suffix in ['.csv', '.xrc', '.txt']:

return path.open('r')

else:

return path.open('rb')

else:

return str(path)</div>

def _get_data_path(*args):

"""

Return the `Path` to a resource file provided by Matplotlib.

``*args`` specify a path relative to the base data path.

"""

return Path(matplotlib.get_data_path(), *args)

<div class="viewcode-block" id="flatten"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.flatten">[docs]</a>def flatten(seq, scalarp=is_scalar_or_string):

"""

Return a generator of flattened nested containers.

For example:

>>> from matplotlib.cbook import flatten

>>> l = (('John', ['Hunter']), (1, 23), [[([42, (5, 23)], )]])

>>> print(list(flatten(l)))

['John', 'Hunter', 1, 23, 42, 5, 23]

By: Composite of Holger Krekel and Luther Blissett

From: https://code.activestate.com/recipes/121294/

and Recipe 1.12 in cookbook

"""

for item in seq:

if scalarp(item) or item is None:

yield item

else:

yield from flatten(item, scalarp)</div>

<div class="viewcode-block" id="get_realpath_and_stat"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.get_realpath_and_stat">[docs]</a>@functools.lru_cache()

def get_realpath_and_stat(path):

realpath = os.path.realpath(path)

stat = os.stat(realpath)

stat_key = (stat.st_ino, stat.st_dev)

return realpath, stat_key</div>

# A regular expression used to determine the amount of space to

# remove. It looks for the first sequence of spaces immediately

# following the first newline, or at the beginning of the string.

_find_dedent_regex = re.compile(r"(?:(?:\n\r?)|^)( *)\S")

# A cache to hold the regexs that actually remove the indent.

_dedent_regex = {}

<div class="viewcode-block" id="dedent"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.dedent">[docs]</a>@deprecated("3.1", alternative="inspect.cleandoc")

def dedent(s):

"""

Remove excess indentation from docstring *s*.

Discards any leading blank lines, then removes up to n whitespace

characters from each line, where n is the number of leading

whitespace characters in the first line. It differs from

textwrap.dedent in its deletion of leading blank lines and its use

of the first non-blank line to determine the indentation.

It is also faster in most cases.

"""

# This implementation has a somewhat obtuse use of regular

# expressions. However, this function accounted for almost 30% of

# matplotlib startup time, so it is worthy of optimization at all

# costs.

if not s: # includes case of s is None

return ''

match = _find_dedent_regex.match(s)

if match is None:

return s

# This is the number of spaces to remove from the left-hand side.

nshift = match.end(1) - match.start(1)

if nshift == 0:

return s

# Get a regex that will remove *up to* nshift spaces from the

# beginning of each line. If it isn't in the cache, generate it.

unindent = _dedent_regex.get(nshift, None)

if unindent is None:

unindent = re.compile("\n\r? {0,%d}" % nshift)

_dedent_regex[nshift] = unindent

result = unindent.sub("\n", s).strip()

return result</div>

<div class="viewcode-block" id="maxdict"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.maxdict">[docs]</a>class maxdict(dict):

"""

A dictionary with a maximum size.

Notes

-----

This doesn't override all the relevant methods to constrain the size,

just ``__setitem__``, so use with caution.

"""

def __init__(self, maxsize):

dict.__init__(self)

self.maxsize = maxsize

self._killkeys = []

def __setitem__(self, k, v):

if k not in self:

if len(self) >= self.maxsize:

del self[self._killkeys[0]]

del self._killkeys[0]

self._killkeys.append(k)

dict.__setitem__(self, k, v)</div>

<div class="viewcode-block" id="Stack"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.Stack">[docs]</a>class Stack:

"""

Stack of elements with a movable cursor.

Mimics home/back/forward in a web browser.

"""

def __init__(self, default=None):

self.clear()

self._default = default

def __call__(self):

"""Return the current element, or None."""

if not len(self._elements):

return self._default

else:

return self._elements[self._pos]

def __len__(self):

return len(self._elements)

def __getitem__(self, ind):

return self._elements[ind]

<div class="viewcode-block" id="Stack.forward"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.Stack.forward">[docs]</a> def forward(self):

"""Move the position forward and return the current element."""

self._pos = min(self._pos + 1, len(self._elements) - 1)

return self()</div>

<div class="viewcode-block" id="Stack.back"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.Stack.back">[docs]</a> def back(self):

"""Move the position back and return the current element."""

if self._pos > 0:

self._pos -= 1

return self()</div>

<div class="viewcode-block" id="Stack.push"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.Stack.push">[docs]</a> def push(self, o):

"""

Push *o* to the stack at current position. Discard all later elements.

*o* is returned.

"""

self._elements = self._elements[:self._pos + 1] + [o]

self._pos = len(self._elements) - 1

return self()</div>

<div class="viewcode-block" id="Stack.home"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.Stack.home">[docs]</a> def home(self):

"""

Push the first element onto the top of the stack.

The first element is returned.

"""

return

self.push(self._elements[0])

return self()</div>

<div class="viewcode-block" id="Stack.empty"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.Stack.empty">[docs]</a> def empty(self):

"""Return whether the stack is empty."""

return len(self._elements) == 0</div>

<div class="viewcode-block" id="Stack.clear"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.Stack.clear">[docs]</a> def clear(self):

"""Empty the stack."""

self._pos = -1

self._elements = []</div>

<div class="viewcode-block" id="Stack.bubble"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.Stack.bubble">[docs]</a> def bubble(self, o):

"""

Raise *o* to the top of the stack. *o* must be present in the stack.

*o* is returned.

"""

if o not in self._elements:

raise ValueError('Unknown element o')

old = self._elements[:]

self.clear()

bubbles = []

for thiso in old:

if thiso == o:

bubbles.append(thiso)

else:

self.push(thiso)

for _ in bubbles:

self.push(o)

return o</div>

<div class="viewcode-block" id="Stack.remove"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.Stack.remove">[docs]</a> def remove(self, o):

"""Remove *o* from the stack."""

raise ValueError('Unknown element o')

old = self._elements[:]

self.clear()

for thiso in old:

if thiso != o:

self.push(thiso)</div></div>

<div class="viewcode-block" id="report_memory"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.report_memory">[docs]</a>def report_memory(i=0): # argument may go away

"""Return the memory consumed by the process."""

def call(command, os_name):

try:

return subprocess.check_output(command)

except subprocess.CalledProcessError:

raise NotImplementedError(

"report_memory works on %s only if "

"the '%s' program is found" % (os_name, command[0])

)

pid = os.getpid()

if sys.platform == 'sunos5':

lines = call(['ps', '-p', '%d' % pid, '-o', 'osz'], 'Sun OS')

mem = int(lines[-1].strip())

elif sys.platform == 'linux':

lines = call(['ps', '-p', '%d' % pid, '-o', 'rss,sz'], 'Linux')

mem = int(lines[1].split()[1])

elif sys.platform == 'darwin':

lines = call(['ps', '-p', '%d' % pid, '-o', 'rss,vsz'], 'Mac OS')

mem = int(lines[1].split()[0])

elif sys.platform == 'win32':

lines = call(["tasklist", "/nh", "/fi", "pid eq %d" % pid], 'Windows')

mem = int(lines.strip().split()[-2].replace(',', ''))

else:

raise NotImplementedError(

"We don't have a memory monitor for %s" % sys.platform)

return mem</div>

_safezip_msg = 'In safezip, len(args[0])=%d but len(args[%d])=%d'

<div class="viewcode-block" id="safezip"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.safezip">[docs]</a>@deprecated("3.1")

def safezip(*args):

"""make sure *args* are equal len before zipping"""

Nx = len(args[0])

for i, arg in enumerate(args[1:]):

if len(arg) != Nx:

raise ValueError(_safezip_msg % (Nx, i + 1, len(arg)))

return list(zip(*args))</div>

<div class="viewcode-block" id="safe_masked_invalid"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.safe_masked_invalid">[docs]</a>def safe_masked_invalid(x, copy=False):

x = np.array(x, subok=True, copy=copy)

if not x.dtype.isnative:

# Note that the argument to `byteswap` is 'inplace',

# thus if we have already made a copy, do the byteswap in

# place, else make a copy with the byte order swapped.

# Be explicit that we are swapping the byte order of the dtype

x = x.byteswap(copy).newbyteorder('S')

try:

xm = np.ma.masked_invalid(x, copy=False)

xm.shrink_mask()

except TypeError:

return x

return xm</div>

<div class="viewcode-block" id="print_cycles"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.print_cycles">[docs]</a>def print_cycles(objects, outstream=sys.stdout, show_progress=False):

"""

Print loops of cyclic references in the given *objects*.

It is often useful to pass in ``gc.garbage`` to find the cycles that are

preventing some objects from being garbage collected.

Parameters

----------

objects

A list of objects to find cycles in.

outstream

The stream for output.

show_progress : bool

If True, print the number of objects reached as they are found.

"""

import gc

def print_path(path):

for i, step in enumerate(path):

# next "wraps around"

next = path[(i + 1) % len(path)]

outstream.write(" %s -- " % type(step))

if isinstance(step, dict):

for key, val in step.items():

if val is next:

outstream.write("[{!r}]".format(key))

break

if key is next:

outstream.write("[key] = {!r}".format(val))

break

elif isinstance(step, list):

outstream.write("[%d]" % step.index(next))

elif isinstance(step, tuple):

outstream.write("( tuple )")

else:

outstream.write(repr(step))

outstream.write(" ->\n")

outstream.write("\n")

def recurse(obj, start, all, current_path):

if show_progress:

outstream.write("%d\r" % len(all))

all[id(obj)] = None

referents = gc.get_referents(obj)

for referent in referents:

# If we've found our way back to the start, this is

# a cycle, so print it out

if referent is start:

print_path(current_path)

# Don't go back through the original list of objects, or

# through temporary references to the object, since those

# are just an artifact of the cycle detector itself.

elif referent is objects or isinstance(referent, types.FrameType):

continue

# We haven't seen this object before, so recurse

elif id(referent) not in all:

recurse(referent, start, all, current_path + [obj])

for obj in objects:

outstream.write(f"Examining: {obj!r}\n")

recurse(obj, obj, {}, [])</div>

<div class="viewcode-block" id="Grouper"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.Grouper">[docs]</a>class Grouper:

"""

This class provides a lightweight way to group arbitrary objects

together into disjoint sets when a full-blown graph data structure

would be overkill.

Objects can be joined using :meth:`join`, tested for connectedness

using :meth:`joined`, and all disjoint sets can be retrieved by

using the object as an iterator.

The objects being joined must be hashable and weak-referenceable.

For example:

>>> from matplotlib.cbook import Grouper

>>> class Foo:

... def __init__(self, s):

... self.s = s

... def __repr__(self):

... return self.s

...

>>> a, b, c, d, e, f = [Foo(x) for x in 'abcdef']

>>> grp = Grouper()

>>> grp.join(a, b)

>>> grp.join(b, c)

>>> grp.join(d, e)

>>> sorted(map(tuple, grp))

[(a, b, c), (d, e)]

>>> grp.joined(a, b)

True

>>> grp.joined(a, c)

True

>>> grp.joined(a, d)

False

"""

def __init__(self, init=()):

self._mapping = {weakref.ref(x): [weakref.ref(x)] for x in init}

def __contains__(self, item):

return weakref.ref(item) in self._mapping

<div class="viewcode-block" id="Grouper.clean"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.Grouper.clean">[docs]</a> def clean(self):

"""Clean dead weak references from the dictionary."""

mapping = self._mapping

to_drop = [key for key in mapping if key() is None]

for key in to_drop:

val = mapping.pop(key)

val.remove(key)</div>

<div class="viewcode-block" id="Grouper.join"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.Grouper.join">[docs]</a> def join(self, a, *args):

"""

Join given arguments into the same set. Accepts one or more arguments.

"""

mapping = self._mapping

set_a = mapping.setdefault(weakref.ref(a), [weakref.ref(a)])

for arg in args:

set_b = mapping.get(weakref.ref(arg), [weakref.ref(arg)])

if set_b is not set_a:

if len(set_b) > len(set_a):

set_a, set_b = set_b, set_a

set_a.extend(set_b)

for elem in set_b:

mapping[elem] = set_a

self.clean()</div>

<div class="viewcode-block" id="Grouper.joined"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.Grouper.joined">[docs]</a> def joined(self, a, b):

"""Return whether *a* and *b* are members of the same set."""

self.clean()

return (self._mapping.get(weakref.ref(a), object())

is self._mapping.get(weakref.ref(b)))</div>

<div class="viewcode-block" id="Grouper.remove"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.Grouper.remove">[docs]</a> def remove(self, a):

self.clean()

set_a = self._mapping.pop(weakref.ref(a), None)

if set_a:

set_a.remove(weakref.ref(a))</div>

def __iter__(self):

"""

Iterate over each of the disjoint sets as a list.

The iterator is invalid if interleaved with calls to join().

"""

self.clean()

unique_groups = {id(group): group for group in self._mapping.values()}

for group in unique_groups.values():

yield [x() for x in group]

<div class="viewcode-block" id="Grouper.get_siblings"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.Grouper.get_siblings">[docs]</a> def get_siblings(self, a):

"""Return all of the items joined with *a*, including itself."""

self.clean()

siblings = self._mapping.get(weakref.ref(a), [weakref.ref(a)])

return [x() for x in siblings]</div></div>

<div class="viewcode-block" id="simple_linear_interpolation"><a class="viewcode-back" href="../../api/cbook_api.html#matplotlib.cbook.simple_linear_interpolation">[docs]</a>def simple_linear_interpolation(a, steps):

"""

Resample an array with ``steps - 1`` points between original point pairs.

Along each column of *a*, ``(steps - 1)`` points are introduced between

each original values; the values are linearly interpolated.

Parameters

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