File: __init__.py

package info (click to toggle)
matplotlib 3.0.2-2
  • links: PTS, VCS
  • area: main
  • in suites: buster
  • size: 77,480 kB
  • sloc: python: 124,525; cpp: 58,549; ansic: 29,599; objc: 2,348; makefile: 148; sh: 57
file content (1824 lines) | stat: -rw-r--r-- 64,086 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
"""
This is an object-oriented plotting library.

A procedural interface is provided by the companion pyplot module,
which may be imported directly, e.g.::

    import matplotlib.pyplot as plt

or using ipython::

    ipython

at your terminal, followed by::

    In [1]: %matplotlib
    In [2]: import matplotlib.pyplot as plt

at the ipython shell prompt.

For the most part, direct use of the object-oriented library is
encouraged when programming; pyplot is primarily for working
interactively.  The
exceptions are the pyplot commands :func:`~matplotlib.pyplot.figure`,
:func:`~matplotlib.pyplot.subplot`,
:func:`~matplotlib.pyplot.subplots`, and
:func:`~pyplot.savefig`, which can greatly simplify scripting.

Modules include:

    :mod:`matplotlib.axes`
        defines the :class:`~matplotlib.axes.Axes` class.  Most pyplot
        commands are wrappers for :class:`~matplotlib.axes.Axes`
        methods.  The axes module is the highest level of OO access to
        the library.

    :mod:`matplotlib.figure`
        defines the :class:`~matplotlib.figure.Figure` class.

    :mod:`matplotlib.artist`
        defines the :class:`~matplotlib.artist.Artist` base class for
        all classes that draw things.

    :mod:`matplotlib.lines`
        defines the :class:`~matplotlib.lines.Line2D` class for
        drawing lines and markers

    :mod:`matplotlib.patches`
        defines classes for drawing polygons

    :mod:`matplotlib.text`
        defines the :class:`~matplotlib.text.Text`,
        :class:`~matplotlib.text.TextWithDash`, and
        :class:`~matplotlib.text.Annotate` classes

    :mod:`matplotlib.image`
        defines the :class:`~matplotlib.image.AxesImage` and
        :class:`~matplotlib.image.FigureImage` classes

    :mod:`matplotlib.collections`
        classes for efficient drawing of groups of lines or polygons

    :mod:`matplotlib.colors`
        classes for interpreting color specifications and for making
        colormaps

    :mod:`matplotlib.cm`
        colormaps and the :class:`~matplotlib.image.ScalarMappable`
        mixin class for providing color mapping functionality to other
        classes

    :mod:`matplotlib.ticker`
        classes for calculating tick mark locations and for formatting
        tick labels

    :mod:`matplotlib.backends`
        a subpackage with modules for various gui libraries and output
        formats

The base matplotlib namespace includes:

    :data:`~matplotlib.rcParams`
        a global dictionary of default configuration settings.  It is
        initialized by code which may be overridden by a matplotlibrc
        file.

    :func:`~matplotlib.rc`
        a function for setting groups of rcParams values

    :func:`~matplotlib.use`
        a function for setting the matplotlib backend.  If used, this
        function must be called immediately after importing matplotlib
        for the first time.  In particular, it must be called
        **before** importing pyplot (if pyplot is imported).

matplotlib was initially written by John D. Hunter (1968-2012) and is now
developed and maintained by a host of others.

Occasionally the internal documentation (python docstrings) will refer
to MATLAB®, a registered trademark of The MathWorks, Inc.

"""
# NOTE: This file must remain Python 2 compatible for the foreseeable future,
# to ensure that we error out properly for existing editable installs.

import sys
if sys.version_info < (3, 5):  # noqa: E402
    raise ImportError("""
Matplotlib 3.0+ does not support Python 2.x, 3.0, 3.1, 3.2, 3.3, or 3.4.
Beginning with Matplotlib 3.0, Python 3.5 and above is required.

See Matplotlib `INSTALL.rst` file for more information:

    https://github.com/matplotlib/matplotlib/blob/master/INSTALL.rst

""")

import atexit
from collections.abc import MutableMapping
import contextlib
import distutils.version
import functools
import io
import importlib
import inspect
from inspect import Parameter
import locale
import logging
import os
from pathlib import Path
import pprint
import re
import shutil
import stat
import subprocess
import tempfile
import urllib.request
import warnings

# cbook must import matplotlib only within function
# definitions, so it is safe to import from it here.
from . import cbook, rcsetup
from matplotlib.cbook import (
    MatplotlibDeprecationWarning, dedent, get_label, sanitize_sequence)
from matplotlib.cbook import mplDeprecation  # deprecated
from matplotlib.rcsetup import defaultParams, validate_backend, cycler

import numpy

# Get the version from the _version.py versioneer file. For a git checkout,
# this is computed based on the number of commits since the last tag.
from ._version import get_versions
__version__ = str(get_versions()['version'])
del get_versions

_log = logging.getLogger(__name__)

__version__numpy__ = '1.10.0'  # minimum required numpy version

__bibtex__ = r"""@Article{Hunter:2007,
  Author    = {Hunter, J. D.},
  Title     = {Matplotlib: A 2D graphics environment},
  Journal   = {Computing In Science \& Engineering},
  Volume    = {9},
  Number    = {3},
  Pages     = {90--95},
  abstract  = {Matplotlib is a 2D graphics package used for Python
  for application development, interactive scripting, and
  publication-quality image generation across user
  interfaces and operating systems.},
  publisher = {IEEE COMPUTER SOC},
  year      = 2007
}"""


def compare_versions(a, b):
    "return True if a is greater than or equal to b"
    if isinstance(a, bytes):
        cbook.warn_deprecated(
            "3.0", "compare_version arguments should be strs.")
        a = a.decode('ascii')
    if isinstance(b, bytes):
        cbook.warn_deprecated(
            "3.0", "compare_version arguments should be strs.")
        b = b.decode('ascii')
    if a:
        a = distutils.version.LooseVersion(a)
        b = distutils.version.LooseVersion(b)
        return a >= b
    else:
        return False


try:
    import dateutil
except ImportError:
    raise ImportError("Matplotlib requires dateutil")


try:
    import pyparsing
except ImportError:
    raise ImportError("Matplotlib requires pyparsing")
else:
    if not compare_versions(pyparsing.__version__, '2.0.1'):
        raise ImportError(
            "Matplotlib requires pyparsing>=2.0.1; you have %s"
            % pyparsing.__version__)


if not compare_versions(numpy.__version__, __version__numpy__):
    raise ImportError(
        "Matplotlib requires numpy>=%s; you have %s" % (
            __version__numpy__, numpy.__version__))


if not hasattr(sys, 'argv'):  # for modpython
    sys.argv = ['modpython']


_verbose_msg = """\
matplotlib.verbose is deprecated;
Command line argument --verbose-LEVEL is deprecated.
This functionality is now provided by the standard
python logging library.  To get more (or less) logging output:
    import logging
    logger = logging.getLogger('matplotlib')
    logger.set_level(logging.INFO)"""


def _set_logger_verbose_level(level_str='silent', file_str='sys.stdout'):
    """
    Use a --verbose-LEVEL level to set the logging level:

    """
    levelmap = {'silent': logging.WARNING, 'helpful': logging.INFO,
                'debug': logging.DEBUG, 'debug-annoying': logging.DEBUG,
                'info': logging.INFO, 'warning': logging.WARNING}
    # Check that current state of logger isn't already more verbose
    # than the requested level.  If it is more verbose, then leave more
    # verbose.
    newlev = levelmap[level_str]
    oldlev = _log.getEffectiveLevel()
    if newlev < oldlev:
        _log.setLevel(newlev)
        std = {
            'sys.stdout': sys.stdout,
            'sys.stderr': sys.stderr,
        }
        if file_str in std:
            fileo = std[file_str]
        else:
            fileo = sys.stdout
            try:
                fileo = open(file_str, 'w')
                # if this fails, we will just write to stdout
            except IOError:
                warnings.warn('could not open log file "{0}"'
                              'for writing.  Check your '
                              'matplotlibrc'.format(file_str))
        console = logging.StreamHandler(fileo)
        console.setLevel(newlev)
        _log.addHandler(console)


def _parse_commandline():
    """
    Check for --verbose-LEVEL type command line arguments and
    set logging level appropriately.
    """

    levels = ('silent', 'helpful', 'debug', 'debug-annoying',
              'info', 'warning')

    for arg in sys.argv[1:]:
        if arg.startswith('--verbose-'):
            level_str = arg[10:]
            # If it doesn't match one of ours, then don't even
            # bother noting it, we are just a 3rd-party library
            # to somebody else's script.
            if level_str in levels:
                _set_logger_verbose_level(level_str)

_parse_commandline()


class Verbose(object):
    """
    A class to handle reporting.  Set the fileo attribute to any file
    instance to handle the output.  Default is sys.stdout
    """
    levels = ('silent', 'helpful', 'debug', 'debug-annoying')
    vald = {level: i for i, level in enumerate(levels)}

    # parse the verbosity from the command line; flags look like
    # --verbose-silent or --verbose-helpful
    _commandLineVerbose = None

    for arg in sys.argv[1:]:
        if not arg.startswith('--verbose-'):
            continue
        level_str = arg[10:]
        # If it doesn't match one of ours, then don't even
        # bother noting it, we are just a 3rd-party library
        # to somebody else's script.
        if level_str in levels:
            _commandLineVerbose = level_str

    @cbook.deprecated("2.2", message=_verbose_msg)
    def __init__(self):
        self.set_level('silent')
        self.fileo = sys.stdout

    @cbook.deprecated("2.2", message=_verbose_msg)
    def set_level(self, level):
        'set the verbosity to one of the Verbose.levels strings'

        if self._commandLineVerbose is not None:
            level = self._commandLineVerbose
        if level not in self.levels:
            warnings.warn('matplotlib: unrecognized --verbose-* string "%s".'
                          ' Legal values are %s' % (level, self.levels))
        else:
            self.level = level

    @cbook.deprecated("2.2", message=_verbose_msg)
    def set_fileo(self, fname):
        std = {
            'sys.stdout': sys.stdout,
            'sys.stderr': sys.stderr,
        }
        if fname in std:
            self.fileo = std[fname]
        else:
            try:
                fileo = open(fname, 'w')
            except IOError:
                raise ValueError('Verbose object could not open log file "{0}"'
                                 ' for writing.\nCheck your matplotlibrc '
                                 'verbose.fileo setting'.format(fname))
            else:
                self.fileo = fileo

    @cbook.deprecated("2.2", message=_verbose_msg)
    def report(self, s, level='helpful'):
        """
        print message s to self.fileo if self.level>=level.  Return
        value indicates whether a message was issued

        """
        if self.ge(level):
            print(s, file=self.fileo)
            return True
        return False

    @cbook.deprecated("2.2", message=_verbose_msg)
    def wrap(self, fmt, func, level='helpful', always=True):
        """
        return a callable function that wraps func and reports it
        output through the verbose handler if current verbosity level
        is higher than level

        if always is True, the report will occur on every function
        call; otherwise only on the first time the function is called
        """
        assert callable(func)

        def wrapper(*args, **kwargs):
            ret = func(*args, **kwargs)

            if (always or not wrapper._spoke):
                spoke = self.report(fmt % ret, level)
                if not wrapper._spoke:
                    wrapper._spoke = spoke
            return ret
        wrapper._spoke = False
        wrapper.__doc__ = func.__doc__
        return wrapper

    @cbook.deprecated("2.2", message=_verbose_msg)
    def ge(self, level):
        'return true if self.level is >= level'
        return self.vald[self.level] >= self.vald[level]


with warnings.catch_warnings():
    warnings.simplefilter("ignore")
    verbose = Verbose()


def _logged_cached(fmt, func=None):
    """
    Decorator that logs a function's return value, and memoizes that value.

    After ::

        @_logged_cached(fmt)
        def func(): ...

    the first call to *func* will log its return value at the DEBUG level using
    %-format string *fmt*, and memoize it; later calls to *func* will directly
    return that value.
    """
    if func is None:  # Return the actual decorator.
        return functools.partial(_logged_cached, fmt)

    called = False
    ret = None

    @functools.wraps(func)
    def wrapper():
        nonlocal called, ret
        if not called:
            ret = func()
            called = True
            _log.debug(fmt, ret)
        return ret

    return wrapper


def checkdep_dvipng():
    try:
        s = subprocess.Popen(['dvipng', '-version'],
                             stdout=subprocess.PIPE,
                             stderr=subprocess.PIPE)
        stdout, stderr = s.communicate()
        line = stdout.decode('ascii').split('\n')[1]
        v = line.split()[-1]
        return v
    except (IndexError, ValueError, OSError):
        return None


def checkdep_ghostscript():
    if checkdep_ghostscript.executable is None:
        if sys.platform == 'win32':
            # mgs is the name in miktex
            gs_execs = ['gswin32c', 'gswin64c', 'mgs', 'gs']
        else:
            gs_execs = ['gs']
        for gs_exec in gs_execs:
            try:
                s = subprocess.Popen(
                    [gs_exec, '--version'], stdout=subprocess.PIPE,
                    stderr=subprocess.PIPE)
                stdout, stderr = s.communicate()
                if s.returncode == 0:
                    v = stdout[:-1].decode('ascii')
                    checkdep_ghostscript.executable = gs_exec
                    checkdep_ghostscript.version = v
            except (IndexError, ValueError, OSError):
                pass
    return checkdep_ghostscript.executable, checkdep_ghostscript.version
checkdep_ghostscript.executable = None
checkdep_ghostscript.version = None


def checkdep_pdftops():
    try:
        s = subprocess.Popen(['pdftops', '-v'], stdout=subprocess.PIPE,
                             stderr=subprocess.PIPE)
        stdout, stderr = s.communicate()
        lines = stderr.decode('ascii').split('\n')
        for line in lines:
            if 'version' in line:
                v = line.split()[-1]
        return v
    except (IndexError, ValueError, UnboundLocalError, OSError):
        return None


def checkdep_inkscape():
    if checkdep_inkscape.version is None:
        try:
            s = subprocess.Popen(['inkscape', '-V'],
                                 stdout=subprocess.PIPE,
                                 stderr=subprocess.PIPE)
            stdout, stderr = s.communicate()
            lines = stdout.decode('ascii').split('\n')
            for line in lines:
                if 'Inkscape' in line:
                    v = line.split()[1]
                    break
            checkdep_inkscape.version = v
        except (IndexError, ValueError, UnboundLocalError, OSError):
            pass
    return checkdep_inkscape.version
checkdep_inkscape.version = None


def checkdep_ps_distiller(s):
    if not s:
        return False

    flag = True
    gs_req = '8.60'
    gs_exec, gs_v = checkdep_ghostscript()
    if not compare_versions(gs_v, gs_req):
        flag = False
        warnings.warn(('matplotlibrc ps.usedistiller option can not be used '
                       'unless ghostscript-%s or later is installed on your '
                       'system') % gs_req)

    if s == 'xpdf':
        pdftops_req = '3.0'
        pdftops_req_alt = '0.9'  # poppler version numbers, ugh
        pdftops_v = checkdep_pdftops()
        if compare_versions(pdftops_v, pdftops_req):
            pass
        elif (compare_versions(pdftops_v, pdftops_req_alt) and not
              compare_versions(pdftops_v, '1.0')):
            pass
        else:
            flag = False
            warnings.warn(('matplotlibrc ps.usedistiller can not be set to '
                           'xpdf unless xpdf-%s or later is installed on '
                           'your system') % pdftops_req)

    if flag:
        return s
    else:
        return False


def checkdep_usetex(s):
    if not s:
        return False

    gs_req = '9.00'
    dvipng_req = '1.6'
    flag = True

    if shutil.which("tex") is None:
        flag = False
        warnings.warn('matplotlibrc text.usetex option can not be used unless '
                      'TeX is installed on your system')

    dvipng_v = checkdep_dvipng()
    if not compare_versions(dvipng_v, dvipng_req):
        flag = False
        warnings.warn('matplotlibrc text.usetex can not be used with *Agg '
                      'backend unless dvipng-%s or later is installed on '
                      'your system' % dvipng_req)

    gs_exec, gs_v = checkdep_ghostscript()
    if not compare_versions(gs_v, gs_req):
        flag = False
        warnings.warn('matplotlibrc text.usetex can not be used unless '
                      'ghostscript-%s or later is installed on your system'
                      % gs_req)

    return flag


@_logged_cached('$HOME=%s')
def get_home():
    """
    Return the user's home directory.

    If the user's home directory cannot be found, return None.
    """
    try:
        return str(Path.home())
    except Exception:
        return None


def _create_tmp_config_dir():
    """
    If the config directory can not be created, create a temporary directory.
    """
    configdir = os.environ['MPLCONFIGDIR'] = (
        tempfile.mkdtemp(prefix='matplotlib-'))
    atexit.register(shutil.rmtree, configdir)
    return configdir


def _get_xdg_config_dir():
    """
    Returns the XDG configuration directory, according to the `XDG
    base directory spec
    <http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html>`_.
    """
    return (os.environ.get('XDG_CONFIG_HOME')
            or (str(Path(get_home(), ".config"))
                if get_home()
                else None))


def _get_xdg_cache_dir():
    """
    Returns the XDG cache directory, according to the `XDG
    base directory spec
    <http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html>`_.
    """
    return (os.environ.get('XDG_CACHE_HOME')
            or (str(Path(get_home(), ".cache"))
                if get_home()
                else None))


def _get_config_or_cache_dir(xdg_base):
    configdir = os.environ.get('MPLCONFIGDIR')
    if configdir:
        configdir = Path(configdir).resolve()
    elif sys.platform.startswith(('linux', 'freebsd')) and xdg_base:
        configdir = Path(xdg_base, "matplotlib")
    elif get_home():
        configdir = Path(get_home(), ".matplotlib")
    else:
        configdir = None

    if configdir:
        try:
            configdir.mkdir(parents=True, exist_ok=True)
        except OSError:
            pass
        else:
            if os.access(str(configdir), os.W_OK) and configdir.is_dir():
                return str(configdir)

    return _create_tmp_config_dir()


@_logged_cached('CONFIGDIR=%s')
def get_configdir():
    """
    Return the string representing the configuration directory.

    The directory is chosen as follows:

    1. If the MPLCONFIGDIR environment variable is supplied, choose that.
    2a. On Linux, follow the XDG specification and look first in
        `$XDG_CONFIG_HOME`, if defined, or `$HOME/.config`.
    2b. On other platforms, choose `$HOME/.matplotlib`.
    3. If the chosen directory exists and is writable, use that as the
       configuration directory.
    4. If possible, create a temporary directory, and use it as the
       configuration directory.
    5. A writable directory could not be found or created; return None.
    """
    return _get_config_or_cache_dir(_get_xdg_config_dir())


@_logged_cached('CACHEDIR=%s')
def get_cachedir():
    """
    Return the location of the cache directory.

    The procedure used to find the directory is the same as for
    _get_config_dir, except using `$XDG_CACHE_HOME`/`~/.cache` instead.
    """
    return _get_config_or_cache_dir(_get_xdg_cache_dir())


def _get_data_path():
    'get the path to matplotlib data'

    if 'MATPLOTLIBDATA' in os.environ:
        path = os.environ['MATPLOTLIBDATA']
        if not os.path.isdir(path):
            raise RuntimeError('Path in environment MATPLOTLIBDATA not a '
                               'directory')
        return path

    return '/usr/share/matplotlib/mpl-data'

    def get_candidate_paths():
        yield Path(__file__).with_name('mpl-data')
        # setuptools' namespace_packages may highjack this init file
        # so need to try something known to be in Matplotlib, not basemap.
        import matplotlib.afm
        yield Path(matplotlib.afm.__file__).with_name('mpl-data')
        # py2exe zips pure python, so still need special check.
        if getattr(sys, 'frozen', None):
            yield Path(sys.executable).with_name('mpl-data')
            # Try again assuming we need to step up one more directory.
            yield Path(sys.executable).parent.with_name('mpl-data')
            # Try again assuming sys.path[0] is a dir not a exe.
            yield Path(sys.path[0]) / 'mpl-data'

    for path in get_candidate_paths():
        if path.is_dir():
            return str(path)

    raise RuntimeError('Could not find the matplotlib data files')


@_logged_cached('matplotlib data path: %s')
def get_data_path():
    if defaultParams['datapath'][0] is None:
        defaultParams['datapath'][0] = _get_data_path()
    return defaultParams['datapath'][0]


def get_py2exe_datafiles():
    data_path = Path(get_data_path())
    d = {}
    for path in filter(Path.is_file, data_path.glob("**/*")):
        (d.setdefault(str(path.parent.relative_to(data_path.parent)), [])
         .append(str(path)))
    return list(d.items())


def matplotlib_fname():
    """
    Get the location of the config file.

    The file location is determined in the following order

    - `$PWD/matplotlibrc`

    - `$MATPLOTLIBRC` if it is a file (or a named pipe, which can be created
      e.g. by process substitution)

    - `$MATPLOTLIBRC/matplotlibrc`

    - `$MPLCONFIGDIR/matplotlibrc`

    - On Linux,

          - `$XDG_CONFIG_HOME/matplotlib/matplotlibrc` (if
            $XDG_CONFIG_HOME is defined)

          - or `$HOME/.config/matplotlib/matplotlibrc` (if
            $XDG_CONFIG_HOME is not defined)

    - On other platforms,

         - `$HOME/.matplotlib/matplotlibrc` if `$HOME` is defined.

    - Lastly, it looks in `$MATPLOTLIBDATA/matplotlibrc` for a
      system-defined copy.
    """

    def gen_candidates():
        yield os.path.join(os.getcwd(), 'matplotlibrc')
        try:
            matplotlibrc = os.environ['MATPLOTLIBRC']
        except KeyError:
            pass
        else:
            yield matplotlibrc
            yield os.path.join(matplotlibrc, 'matplotlibrc')
        yield os.path.join(get_configdir(), 'matplotlibrc')
        yield '/etc/matplotlibrc'

    for fname in gen_candidates():
        if os.path.exists(fname):
            st_mode = os.stat(fname).st_mode
            if stat.S_ISREG(st_mode) or stat.S_ISFIFO(st_mode):
                break
    # Return first candidate that is a file, or last candidate if none is
    # valid (in that case, a warning is raised at startup by `rc_params`).
    return fname


# rcParams deprecated and automatically mapped to another key.
# Values are tuples of (version, new_name, f_old2new, f_new2old).
_deprecated_map = {}

# rcParams deprecated; some can manually be mapped to another key.
# Values are tuples of (version, new_name_or_None).
_deprecated_ignore_map = {
    'text.dvipnghack': ('2.1', None),
    'nbagg.transparent': ('2.2', 'figure.facecolor'),
    'plugins.directory': ('2.2', None),
    'pgf.debug': ('3.0', None),
}

# rcParams deprecated; can use None to suppress warnings; remain actually
# listed in the rcParams (not included in _all_deprecated).
# Values are typles of (version,)
_deprecated_remain_as_none = {
    'axes.hold': ('2.1',),
    'backend.qt4': ('2.2',),
    'backend.qt5': ('2.2',),
    'text.latex.unicode': ('3.0',),
}


_all_deprecated = {*_deprecated_map, *_deprecated_ignore_map}


class RcParams(MutableMapping, dict):

    """
    A dictionary object including validation

    validating functions are defined and associated with rc parameters in
    :mod:`matplotlib.rcsetup`
    """

    validate = {key: converter
                for key, (default, converter) in defaultParams.items()
                if key not in _all_deprecated}

    @property
    @cbook.deprecated("3.0")
    def msg_depr(self):
        return "%s is deprecated and replaced with %s; please use the latter."

    @property
    @cbook.deprecated("3.0")
    def msg_depr_ignore(self):
        return "%s is deprecated and ignored. Use %s instead."

    @property
    @cbook.deprecated("3.0")
    def msg_depr_set(self):
        return ("%s is deprecated. Please remove it from your matplotlibrc "
                "and/or style files.")

    @property
    @cbook.deprecated("3.0")
    def msg_obsolete(self):
        return ("%s is obsolete. Please remove it from your matplotlibrc "
                "and/or style files.")

    @property
    @cbook.deprecated("3.0")
    def msg_backend_obsolete(self):
        return ("The {} rcParam was deprecated in version 2.2.  In order to "
                "force the use of a specific Qt binding, either import that "
                "binding first, or set the QT_API environment variable.")

    # validate values on the way in
    def __init__(self, *args, **kwargs):
        self.update(*args, **kwargs)

    def __setitem__(self, key, val):
        try:
            if key in _deprecated_map:
                version, alt_key, alt_val, inverse_alt = _deprecated_map[key]
                cbook.warn_deprecated(
                    version, key, obj_type="rcparam", alternative=alt_key)
                key = alt_key
                val = alt_val(val)
            elif key in _deprecated_remain_as_none and val is not None:
                version, = _deprecated_remain_as_none[key]
                addendum = ''
                if key.startswith('backend'):
                    addendum = (
                        "In order to force the use of a specific Qt binding, "
                        "either import that binding first, or set the QT_API "
                        "environment variable.")
                cbook.warn_deprecated(
                    "2.2", name=key, obj_type="rcparam", addendum=addendum)
            elif key in _deprecated_ignore_map:
                version, alt_key = _deprecated_ignore_map[key]
                cbook.warn_deprecated(
                    version, name=key, obj_type="rcparam", alternative=alt_key)
                return
            elif key == 'examples.directory':
                cbook.warn_deprecated(
                    "3.0", "{} is deprecated; in the future, examples will be "
                    "found relative to the 'datapath' directory.".format(key))
            elif key == 'backend':
                if val is rcsetup._auto_backend_sentinel:
                    if 'backend' in self:
                        return
            try:
                cval = self.validate[key](val)
            except ValueError as ve:
                raise ValueError("Key %s: %s" % (key, str(ve)))
            dict.__setitem__(self, key, cval)
        except KeyError:
            raise KeyError(
                '%s is not a valid rc parameter. See rcParams.keys() for a '
                'list of valid parameters.' % (key,))

    def __getitem__(self, key):
        if key in _deprecated_map:
            version, alt_key, alt_val, inverse_alt = _deprecated_map[key]
            cbook.warn_deprecated(
                version, key, obj_type="rcparam", alternative=alt_key)
            return inverse_alt(dict.__getitem__(self, alt_key))

        elif key in _deprecated_ignore_map:
            version, alt_key = _deprecated_ignore_map[key]
            cbook.warn_deprecated(
                version, key, obj_type="rcparam", alternative=alt_key)
            return dict.__getitem__(self, alt_key) if alt_key else None

        elif key == 'examples.directory':
            cbook.warn_deprecated(
                "3.0", "{} is deprecated; in the future, examples will be "
                "found relative to the 'datapath' directory.".format(key))

        elif key == "backend":
            val = dict.__getitem__(self, key)
            if val is rcsetup._auto_backend_sentinel:
                from matplotlib import pyplot as plt
                plt.switch_backend(rcsetup._auto_backend_sentinel)

        return dict.__getitem__(self, key)

    def __repr__(self):
        class_name = self.__class__.__name__
        indent = len(class_name) + 1
        repr_split = pprint.pformat(dict(self), indent=1,
                                    width=80 - indent).split('\n')
        repr_indented = ('\n' + ' ' * indent).join(repr_split)
        return '{}({})'.format(class_name, repr_indented)

    def __str__(self):
        return '\n'.join(map('{0[0]}: {0[1]}'.format, sorted(self.items())))

    def __iter__(self):
        """Yield sorted list of keys."""
        with warnings.catch_warnings():
            warnings.simplefilter('ignore', MatplotlibDeprecationWarning)
            yield from sorted(dict.__iter__(self))

    def __len__(self):
        return dict.__len__(self)

    def find_all(self, pattern):
        """
        Return the subset of this RcParams dictionary whose keys match,
        using :func:`re.search`, the given ``pattern``.

        .. note::

            Changes to the returned dictionary are *not* propagated to
            the parent RcParams dictionary.

        """
        pattern_re = re.compile(pattern)
        return RcParams((key, value)
                        for key, value in self.items()
                        if pattern_re.search(key))

    def copy(self):
        return {k: dict.__getitem__(self, k) for k in self}


def rc_params(fail_on_error=False):
    """Return a :class:`matplotlib.RcParams` instance from the
    default matplotlib rc file.
    """
    fname = matplotlib_fname()
    if not os.path.exists(fname):
        # this should never happen, default in mpl-data should always be found
        message = 'could not find rc file; returning defaults'
        ret = RcParams([(key, default) for key, (default, _) in
                        defaultParams.items()
                        if key not in _all_deprecated])
        warnings.warn(message)
        return ret

    return rc_params_from_file(fname, fail_on_error)


URL_REGEX = re.compile(r'http://|https://|ftp://|file://|file:\\')


def is_url(filename):
    """Return True if string is an http, ftp, or file URL path."""
    return URL_REGEX.match(filename) is not None


@contextlib.contextmanager
def _open_file_or_url(fname):
    if is_url(fname):
        with urllib.request.urlopen(fname) as f:
            yield (line.decode('utf-8') for line in f)
    else:
        fname = os.path.expanduser(fname)
        encoding = locale.getpreferredencoding(do_setlocale=False)
        if encoding is None:
            encoding = "utf-8"
        with open(fname, encoding=encoding) as f:
            yield f


_error_details_fmt = 'line #%d\n\t"%s"\n\tin file "%s"'


def _rc_params_in_file(fname, fail_on_error=False):
    """Return :class:`matplotlib.RcParams` from the contents of the given file.

    Unlike `rc_params_from_file`, the configuration class only contains the
    parameters specified in the file (i.e. default values are not filled in).
    """
    cnt = 0
    rc_temp = {}
    with _open_file_or_url(fname) as fd:
        try:
            for line in fd:
                cnt += 1
                strippedline = line.split('#', 1)[0].strip()
                if not strippedline:
                    continue
                tup = strippedline.split(':', 1)
                if len(tup) != 2:
                    error_details = _error_details_fmt % (cnt, line, fname)
                    warnings.warn('Illegal %s' % error_details)
                    continue
                key, val = tup
                key = key.strip()
                val = val.strip()
                if key in rc_temp:
                    warnings.warn('Duplicate key in file "%s", line #%d' %
                                  (fname, cnt))
                rc_temp[key] = (val, line, cnt)
        except UnicodeDecodeError:
            warnings.warn(
                ('Cannot decode configuration file %s with '
                 'encoding %s, check LANG and LC_* variables')
                % (fname, locale.getpreferredencoding(do_setlocale=False) or
                   'utf-8 (default)'))
            raise

    config = RcParams()

    for key in ('verbose.level', 'verbose.fileo'):
        if key in rc_temp:
            val, line, cnt = rc_temp.pop(key)
            if fail_on_error:
                config[key] = val  # try to convert to proper type or raise
            else:
                try:
                    config[key] = val  # try to convert to proper type or skip
                except Exception as msg:
                    error_details = _error_details_fmt % (cnt, line, fname)
                    warnings.warn('Bad val "%s" on %s\n\t%s' %
                                  (val, error_details, msg))

    for key, (val, line, cnt) in rc_temp.items():
        if key in defaultParams:
            if fail_on_error:
                config[key] = val  # try to convert to proper type or raise
            else:
                try:
                    config[key] = val  # try to convert to proper type or skip
                except Exception as msg:
                    error_details = _error_details_fmt % (cnt, line, fname)
                    warnings.warn('Bad val "%s" on %s\n\t%s' %
                                  (val, error_details, msg))
        elif key in _deprecated_ignore_map:
            version, alt_key = _deprecated_ignore_map[key]
            cbook.warn_deprecated(
                version, key, alternative=alt_key,
                addendum="Please update your matplotlibrc.")
        else:
            print("""
Bad key "%s" on line %d in
%s.
You probably need to get an updated matplotlibrc file from
http://github.com/matplotlib/matplotlib/blob/master/matplotlibrc.template
or from the matplotlib source distribution""" % (key, cnt, fname),
                  file=sys.stderr)

    return config


def rc_params_from_file(fname, fail_on_error=False, use_default_template=True):
    """Return :class:`matplotlib.RcParams` from the contents of the given file.

    Parameters
    ----------
    fname : str
        Name of file parsed for matplotlib settings.
    fail_on_error : bool
        If True, raise an error when the parser fails to convert a parameter.
    use_default_template : bool
        If True, initialize with default parameters before updating with those
        in the given file. If False, the configuration class only contains the
        parameters specified in the file. (Useful for updating dicts.)
    """
    config_from_file = _rc_params_in_file(fname, fail_on_error)

    if not use_default_template:
        return config_from_file

    iter_params = defaultParams.items()
    with warnings.catch_warnings():
        warnings.simplefilter("ignore", MatplotlibDeprecationWarning)
        config = RcParams([(key, default) for key, (default, _) in iter_params
                           if key not in _all_deprecated])
    config.update(config_from_file)

    if config['datapath'] is None:
        config['datapath'] = get_data_path()

    if "".join(config['text.latex.preamble']):
        _log.info("""
*****************************************************************
You have the following UNSUPPORTED LaTeX preamble customizations:
%s
Please do not ask for support with these customizations active.
*****************************************************************
""", '\n'.join(config['text.latex.preamble']))
    _log.debug('loaded rc file %s', fname)

    return config


# this is the instance used by the matplotlib classes
rcParams = rc_params()

# Don't trigger deprecation warning when just fetching.
if dict.__getitem__(rcParams, 'examples.directory'):
    # paths that are intended to be relative to matplotlib_fname()
    # are allowed for the examples.directory parameter.
    # However, we will need to fully qualify the path because
    # Sphinx requires absolute paths.
    if not os.path.isabs(rcParams['examples.directory']):
        _basedir, _fname = os.path.split(matplotlib_fname())
        # Sometimes matplotlib_fname() can return relative paths,
        # Also, using realpath() guarantees that Sphinx will use
        # the same path that matplotlib sees (in case of weird symlinks).
        _basedir = os.path.realpath(_basedir)
        _fullpath = os.path.join(_basedir, rcParams['examples.directory'])
        rcParams['examples.directory'] = _fullpath


with warnings.catch_warnings():
    warnings.simplefilter("ignore", MatplotlibDeprecationWarning)
    rcParamsOrig = RcParams(rcParams.copy())
    rcParamsDefault = RcParams([(key, default) for key, (default, converter) in
                                defaultParams.items()
                                if key not in _all_deprecated])

rcParams['ps.usedistiller'] = checkdep_ps_distiller(
                      rcParams['ps.usedistiller'])

rcParams['text.usetex'] = checkdep_usetex(rcParams['text.usetex'])

if rcParams['axes.formatter.use_locale']:
    locale.setlocale(locale.LC_ALL, '')


def rc(group, **kwargs):
    """
    Set the current rc params.  *group* is the grouping for the rc, e.g.,
    for ``lines.linewidth`` the group is ``lines``, for
    ``axes.facecolor``, the group is ``axes``, and so on.  Group may
    also be a list or tuple of group names, e.g., (*xtick*, *ytick*).
    *kwargs* is a dictionary attribute name/value pairs, e.g.,::

      rc('lines', linewidth=2, color='r')

    sets the current rc params and is equivalent to::

      rcParams['lines.linewidth'] = 2
      rcParams['lines.color'] = 'r'

    The following aliases are available to save typing for interactive
    users:

    =====   =================
    Alias   Property
    =====   =================
    'lw'    'linewidth'
    'ls'    'linestyle'
    'c'     'color'
    'fc'    'facecolor'
    'ec'    'edgecolor'
    'mew'   'markeredgewidth'
    'aa'    'antialiased'
    =====   =================

    Thus you could abbreviate the above rc command as::

          rc('lines', lw=2, c='r')


    Note you can use python's kwargs dictionary facility to store
    dictionaries of default parameters.  e.g., you can customize the
    font rc as follows::

      font = {'family' : 'monospace',
              'weight' : 'bold',
              'size'   : 'larger'}

      rc('font', **font)  # pass in the font dict as kwargs

    This enables you to easily switch between several configurations.  Use
    ``matplotlib.style.use('default')`` or :func:`~matplotlib.rcdefaults` to
    restore the default rc params after changes.
    """

    aliases = {
        'lw':  'linewidth',
        'ls':  'linestyle',
        'c':   'color',
        'fc':  'facecolor',
        'ec':  'edgecolor',
        'mew': 'markeredgewidth',
        'aa':  'antialiased',
        }

    if isinstance(group, str):
        group = (group,)
    for g in group:
        for k, v in kwargs.items():
            name = aliases.get(k) or k
            key = '%s.%s' % (g, name)
            try:
                rcParams[key] = v
            except KeyError:
                raise KeyError(('Unrecognized key "%s" for group "%s" and '
                                'name "%s"') % (key, g, name))


def rcdefaults():
    """
    Restore the rc params from Matplotlib's internal default style.

    Style-blacklisted rc params (defined in
    `matplotlib.style.core.STYLE_BLACKLIST`) are not updated.

    See Also
    --------
    rc_file_defaults :
        Restore the rc params from the rc file originally loaded by Matplotlib.
    matplotlib.style.use :
        Use a specific style file.  Call ``style.use('default')`` to restore
        the default style.
    """
    # Deprecation warnings were already handled when creating rcParamsDefault,
    # no need to reemit them here.
    with warnings.catch_warnings():
        warnings.simplefilter("ignore", mplDeprecation)
        from .style.core import STYLE_BLACKLIST
        rcParams.clear()
        rcParams.update({k: v for k, v in rcParamsDefault.items()
                         if k not in STYLE_BLACKLIST})


def rc_file_defaults():
    """
    Restore the rc params from the original rc file loaded by Matplotlib.

    Style-blacklisted rc params (defined in
    `matplotlib.style.core.STYLE_BLACKLIST`) are not updated.
    """
    # Deprecation warnings were already handled when creating rcParamsOrig, no
    # need to reemit them here.
    with warnings.catch_warnings():
        warnings.simplefilter("ignore", mplDeprecation)
        from .style.core import STYLE_BLACKLIST
        rcParams.update({k: rcParamsOrig[k] for k in rcParamsOrig
                         if k not in STYLE_BLACKLIST})


def rc_file(fname):
    """
    Update rc params from file.

    Style-blacklisted rc params (defined in
    `matplotlib.style.core.STYLE_BLACKLIST`) are not updated.
    """
    # Deprecation warnings were already handled in rc_params_from_file, no need
    # to reemit them here.
    with warnings.catch_warnings():
        warnings.simplefilter("ignore", mplDeprecation)
        from .style.core import STYLE_BLACKLIST
        rc_from_file = rc_params_from_file(fname)
        rcParams.update({k: rc_from_file[k] for k in rc_from_file
                         if k not in STYLE_BLACKLIST})


class rc_context:
    """
    Return a context manager for managing rc settings.

    This allows one to do::

        with mpl.rc_context(fname='screen.rc'):
            plt.plot(x, a)
            with mpl.rc_context(fname='print.rc'):
                plt.plot(x, b)
            plt.plot(x, c)

    The 'a' vs 'x' and 'c' vs 'x' plots would have settings from
    'screen.rc', while the 'b' vs 'x' plot would have settings from
    'print.rc'.

    A dictionary can also be passed to the context manager::

        with mpl.rc_context(rc={'text.usetex': True}, fname='screen.rc'):
            plt.plot(x, a)

    The 'rc' dictionary takes precedence over the settings loaded from
    'fname'.  Passing a dictionary only is also valid. For example a
    common usage is::

        with mpl.rc_context(rc={'interactive': False}):
            fig, ax = plt.subplots()
            ax.plot(range(3), range(3))
            fig.savefig('A.png', format='png')
            plt.close(fig)
    """
    # While it may seem natural to implement rc_context using
    # contextlib.contextmanager, that would entail always calling the finally:
    # clause of the contextmanager (which restores the original rcs) including
    # during garbage collection; as a result, something like `plt.xkcd();
    # gc.collect()` would result in the style being lost (as `xkcd()` is
    # implemented on top of rc_context, and nothing is holding onto context
    # manager except possibly circular references.

    def __init__(self, rc=None, fname=None):
        self._orig = rcParams.copy()
        try:
            if fname:
                rc_file(fname)
            if rc:
                rcParams.update(rc)
        except Exception:
            self.__fallback()
            raise

    def __fallback(self):
        # If anything goes wrong, revert to the original rcs.
        updated_backend = self._orig['backend']
        dict.update(rcParams, self._orig)
        # except for the backend.  If the context block triggered resloving
        # the auto backend resolution keep that value around
        if self._orig['backend'] is rcsetup._auto_backend_sentinel:
            rcParams['backend'] = updated_backend

    def __enter__(self):
        return self

    def __exit__(self, exc_type, exc_value, exc_tb):
        self.__fallback()


def use(arg, warn=False, force=True):
    """
    Set the matplotlib backend to one of the known backends.

    Parameters
    ----------
    arg : str
        The backend to switch to.  This can either be one of the
        'standard' backend names:

        - interactive backends:
          GTK3Agg, GTK3Cairo, MacOSX, nbAgg,
          Qt4Agg, Qt4Cairo, Qt5Agg, Qt5Cairo,
          TkAgg, TkCairo, WebAgg, WX, WXAgg, WXCairo

        - non-interactive backends:
          agg, cairo, pdf, pgf, ps, svg, template

        or a string of the form: ``module://my.module.name``.

        Note: Standard backend names are case-insensitive here.

    warn : bool, optional
        If True, warn if this is called after pyplot has been imported
        and a backend is set up.

        defaults to False.

    force : bool, optional
        If True, attempt to switch the backend.   An ImportError is raised if
        an interactive backend is selected, but another interactive
        backend has already started.  This defaults to True.

    See Also
    --------
    :ref:`backends`
    matplotlib.get_backend
    """
    name = validate_backend(arg)

    # if setting back to the same thing, do nothing
    if (dict.__getitem__(rcParams, 'backend') == name):
        pass

    # Check if we have already imported pyplot and triggered
    # backend selection, do a bit more work
    elif 'matplotlib.pyplot' in sys.modules:
        # If we are here then the requested is different than the current.
        # If we are going to force the switch, never warn, else, if warn
        # is True, then direct users to `plt.switch_backend`
        if (not force) and warn:
            warnings.warn(
                ("matplotlib.pyplot as already been imported, "
                 "this call will have no effect."),
                stacklevel=2)

        # if we are going to force switching the backend, pull in
        # `switch_backend` from pyplot.  This will only happen if
        # pyplot is already imported.
        if force:
            from matplotlib.pyplot import switch_backend
            switch_backend(name)
    # Finally if pyplot is not imported update both rcParams and
    # rcDefaults so restoring the defaults later with rcdefaults
    # won't change the backend.  This is a bit of overkill as 'backend'
    # is already in style.core.STYLE_BLACKLIST, but better to be safe.
    else:
        rcParams['backend'] = rcParamsDefault['backend'] = name


if os.environ.get('MPLBACKEND'):
    rcParams['backend'] = os.environ.get('MPLBACKEND')


def get_backend():
    """
    Return the name of the current backend.

    See Also
    --------
    matplotlib.use
    """
    return rcParams['backend']


def interactive(b):
    """
    Set interactive mode to boolean b.

    If b is True, then draw after every plotting command, e.g., after xlabel
    """
    rcParams['interactive'] = b


def is_interactive():
    'Return true if plot mode is interactive'
    return rcParams['interactive']


def tk_window_focus():
    """Return true if focus maintenance under TkAgg on win32 is on.
     This currently works only for python.exe and IPython.exe.
     Both IDLE and Pythonwin.exe fail badly when tk_window_focus is on."""
    if rcParams['backend'] != 'TkAgg':
        return False
    return rcParams['tk.window_focus']


default_test_modules = [
    'matplotlib.tests',
    'matplotlib.sphinxext.tests',
    'mpl_toolkits.tests',
]


def _init_tests():
    # CPython's faulthandler since v3.6 handles exceptions on Windows
    # https://bugs.python.org/issue23848 but until v3.6.4 it was printing
    # non-fatal exceptions https://bugs.python.org/issue30557
    import platform
    if not (sys.platform == 'win32' and
            (3, 6) < sys.version_info < (3, 6, 4) and
            platform.python_implementation() == 'CPython'):
        import faulthandler
        faulthandler.enable()

    # The version of FreeType to install locally for running the
    # tests.  This must match the value in `setupext.py`
    LOCAL_FREETYPE_VERSION = '2.6.1'

    from matplotlib import ft2font
    if (ft2font.__freetype_version__ != LOCAL_FREETYPE_VERSION or
        ft2font.__freetype_build_type__ != 'local'):
        warnings.warn(
            "Matplotlib is not built with the correct FreeType version to run "
            "tests.  Set local_freetype=True in setup.cfg and rebuild. "
            "Expect many image comparison failures below. "
            "Expected freetype version {0}. "
            "Found freetype version {1}. "
            "Freetype build type is {2}local".format(
                LOCAL_FREETYPE_VERSION,
                ft2font.__freetype_version__,
                "" if ft2font.__freetype_build_type__ == 'local' else "not "
            )
        )

    try:
        import pytest
    except ImportError:
        print("matplotlib.test requires pytest to run.")
        raise


def test(verbosity=None, coverage=False, switch_backend_warn=True,
         recursionlimit=0, **kwargs):
    """run the matplotlib test suite"""
    _init_tests()
    if not os.path.isdir(os.path.join(os.path.dirname(__file__), 'tests')):
        raise ImportError("Matplotlib test data is not installed")

    old_backend = get_backend()
    old_recursionlimit = sys.getrecursionlimit()
    try:
        use('agg')
        if recursionlimit:
            sys.setrecursionlimit(recursionlimit)
        import pytest

        args = kwargs.pop('argv', [])
        provide_default_modules = True
        use_pyargs = True
        for arg in args:
            if any(arg.startswith(module_path)
                   for module_path in default_test_modules):
                provide_default_modules = False
                break
            if os.path.exists(arg):
                provide_default_modules = False
                use_pyargs = False
                break
        if use_pyargs:
            args += ['--pyargs']
        if provide_default_modules:
            args += default_test_modules

        if coverage:
            args += ['--cov']

        if verbosity:
            args += ['-' + 'v' * verbosity]

        retcode = pytest.main(args, **kwargs)
    finally:
        if old_backend.lower() != 'agg':
            use(old_backend, warn=switch_backend_warn)
        if recursionlimit:
            sys.setrecursionlimit(old_recursionlimit)

    return retcode


test.__test__ = False  # pytest: this function is not a test


def _replacer(data, key):
    """Either returns data[key] or passes data back. Also
    converts input data to a sequence as needed.
    """
    # if key isn't a string don't bother
    if not isinstance(key, str):
        return key
    # try to use __getitem__
    try:
        return sanitize_sequence(data[key])
    # key does not exist, silently fall back to key
    except KeyError:
        return key


_DATA_DOC_APPENDIX = """

.. note::
    In addition to the above described arguments, this function can take a
    **data** keyword argument. If such a **data** argument is given, the
    following arguments are replaced by **data[<arg>]**:

    {replaced}

    Objects passed as **data** must support item access (``data[<arg>]``) and
    membership test (``<arg> in data``).
"""


def _add_data_doc(docstring, replace_names, replace_all_args):
    """Add documentation for a *data* field to the given docstring.

    Parameters
    ----------
    docstring : str
        The input docstring.
    replace_names : list of strings or None
        The list of parameter names which arguments should be replaced by
        `data[name]`. If None, all arguments are replaced if they are
        included in `data`.
    replace_all_args : bool
        If True, all arguments in *args get replaced, even if they are not
        in replace_names.

    Returns
    -------
        The augmented docstring.
    """
    if docstring is None:
        docstring = ''
    else:
        docstring = dedent(docstring)
    _repl = ""
    if replace_names is None:
        _repl = "* All positional and all keyword arguments."
    else:
        if len(replace_names) != 0:
            _repl = "* All arguments with the following names: '{names}'."
        if replace_all_args:
            _repl += "\n    * All positional arguments."
        _repl = _repl.format(names="', '".join(sorted(replace_names)))
    return docstring + _DATA_DOC_APPENDIX.format(replaced=_repl)


def _preprocess_data(replace_names=None, replace_all_args=False,
                     label_namer=None, positional_parameter_names=None):
    """
    A decorator to add a 'data' kwarg to any a function.  The signature
    of the input function must include the ax argument at the first position ::

       def foo(ax, *args, **kwargs)

    so this is suitable for use with Axes methods.

    Parameters
    ----------
    replace_names : list of strings, optional, default: None
        The list of parameter names which arguments should be replaced by
        `data[name]`. If None, all arguments are replaced if they are
        included in `data`.
    replace_all_args : bool, default: False
        If True, all arguments in *args get replaced, even if they are not
        in replace_names.
    label_namer : string, optional, default: None
        The name of the parameter which argument should be used as label, if
        label is not set. If None, the label keyword argument is not set.
    positional_parameter_names : list of strings or callable, optional
        The full list of positional parameter names (excluding an explicit
        `ax`/'self' argument at the first place and including all possible
        positional parameter in `*args`), in the right order. Can also include
        all other keyword parameter. Only needed if the wrapped function does
        contain `*args` and (replace_names is not None or replace_all_args is
        False). If it is a callable, it will be called with the actual
        tuple of *args and the data and should return a list like
        above.
        NOTE: callables should only be used when the names and order of *args
        can only be determined at runtime. Please use list of names
        when the order and names of *args is clear before runtime!

    .. note:: decorator also converts MappingView input data to list.
    """
    if replace_names is not None:
        replace_names = set(replace_names)

    def param(func):
        sig = inspect.signature(func)
        _has_varargs = False
        _has_varkwargs = False
        _arg_names = []
        params = list(sig.parameters.values())
        for p in params:
            if p.kind is Parameter.VAR_POSITIONAL:
                _has_varargs = True
            elif p.kind is Parameter.VAR_KEYWORD:
                _has_varkwargs = True
            else:
                _arg_names.append(p.name)
        data_param = Parameter('data', Parameter.KEYWORD_ONLY, default=None)
        if _has_varkwargs:
            params.insert(-1, data_param)
        else:
            params.append(data_param)
        new_sig = sig.replace(parameters=params)
        # Import-time check: do we have enough information to replace *args?
        arg_names_at_runtime = False
        # there can't be any positional arguments behind *args and no
        # positional args can end up in **kwargs, so only *varargs make
        # problems.
        # http://stupidpythonideas.blogspot.de/2013/08/arguments-and-parameters.html
        if not _has_varargs:
            # all args are "named", so no problem
            # remove the first "ax" / self arg
            arg_names = _arg_names[1:]
        else:
            # Here we have "unnamed" variables and we need a way to determine
            # whether to replace a arg or not
            if replace_names is None:
                # all argnames should be replaced
                arg_names = None
            elif len(replace_names) == 0:
                # No argnames should be replaced
                arg_names = []
            elif len(_arg_names) > 1 and (positional_parameter_names is None):
                # we got no manual parameter names but more than an 'ax' ...
                if len(replace_names - set(_arg_names[1:])) == 0:
                    # all to be replaced arguments are in the list
                    arg_names = _arg_names[1:]
                else:
                    raise AssertionError(
                        "Got unknown 'replace_names' and wrapped function "
                        "{!r} uses '*args', need 'positional_parameter_names'"
                        .format(func.__name__))
            else:
                if positional_parameter_names is not None:
                    if callable(positional_parameter_names):
                        # determined by the function at runtime
                        arg_names_at_runtime = True
                        # so that we don't compute the label_pos at import time
                        arg_names = []
                    else:
                        arg_names = positional_parameter_names
                else:
                    if replace_all_args:
                        arg_names = []
                    else:
                        raise AssertionError(
                            "Got 'replace_names' and wrapped function {!r} "
                            "uses *args, need 'positional_parameter_names' or "
                            "'replace_all_args'".format(func.__name__))

        # compute the possible label_namer and label position in positional
        # arguments
        label_pos = 9999  # bigger than all "possible" argument lists
        label_namer_pos = 9999  # bigger than all "possible" argument lists
        if (label_namer and  # we actually want a label here ...
                arg_names and  # and we can determine a label in *args ...
                label_namer in arg_names):  # and it is in *args
            label_namer_pos = arg_names.index(label_namer)
            if "label" in arg_names:
                label_pos = arg_names.index("label")

        # Check the case we know a label_namer but we can't find it the
        # arg_names... Unfortunately the label_namer can be in **kwargs,
        # which we can't detect here and which results in a non-set label
        # which might surprise the user :-(
        if label_namer and not arg_names_at_runtime and not _has_varkwargs:
            if not arg_names:
                raise AssertionError(
                    "label_namer {!r} can't be found as the parameter without "
                    "'positional_parameter_names'".format(label_namer))
            elif label_namer not in arg_names:
                raise AssertionError(
                    "label_namer {!r} can't be found in the parameter names "
                    "(known argnames: %s).".format(label_namer, arg_names))
            else:
                # this is the case when the name is in arg_names
                pass

        @functools.wraps(func)
        def inner(ax, *args, data=None, **kwargs):
            # this is needed because we want to change these values if
            # arg_names_at_runtime==True, but python does not allow assigning
            # to a variable in a outer scope. So use some new local ones and
            # set them to the already computed values.
            _label_pos = label_pos
            _label_namer_pos = label_namer_pos
            _arg_names = arg_names

            label = None

            if data is None:  # data validation
                args = tuple(sanitize_sequence(a) for a in args)
            else:
                if arg_names_at_runtime:
                    # update the information about replace names and
                    # label position
                    _arg_names = positional_parameter_names(args, data)
                    if (label_namer and  # we actually want a label here ...
                            _arg_names and  # and we can find a label in *args
                            (label_namer in _arg_names)):  # and it is in *args
                        _label_namer_pos = _arg_names.index(label_namer)
                        if "label" in _arg_names:
                            _label_pos = arg_names.index("label")

                # save the current label_namer value so that it can be used as
                # a label
                if _label_namer_pos < len(args):
                    label = args[_label_namer_pos]
                else:
                    label = kwargs.get(label_namer, None)
                # ensure a string, as label can't be anything else
                if not isinstance(label, str):
                    label = None

                if (replace_names is None) or (replace_all_args is True):
                    # all should be replaced
                    args = tuple(_replacer(data, a) for
                                 j, a in enumerate(args))
                else:
                    # An arg is replaced if the arg_name of that position is
                    #   in replace_names ...
                    if len(_arg_names) < len(args):
                        raise RuntimeError(
                            "Got more args than function expects")
                    args = tuple(_replacer(data, a)
                                 if _arg_names[j] in replace_names else a
                                 for j, a in enumerate(args))

                if replace_names is None:
                    # replace all kwargs ...
                    kwargs = {k: _replacer(data, v) for k, v in kwargs.items()}
                else:
                    # ... or only if a kwarg of that name is in replace_names
                    kwargs = {
                        k: _replacer(data, v) if k in replace_names else v
                        for k, v in kwargs.items()}

            # replace the label if this func "wants" a label arg and the user
            # didn't set one. Note: if the user puts in "label=None", it does
            # *NOT* get replaced!
            user_supplied_label = (
                len(args) >= _label_pos or  # label is included in args
                'label' in kwargs  # ... or in kwargs
            )
            if label_namer and not user_supplied_label:
                if _label_namer_pos < len(args):
                    kwargs['label'] = get_label(args[_label_namer_pos], label)
                elif label_namer in kwargs:
                    kwargs['label'] = get_label(kwargs[label_namer], label)
                else:
                    warnings.warn(
                        "Tried to set a label via parameter %r in func %r but "
                        "couldn't find such an argument.\n"
                        "(This is a programming error, please report to "
                        "the Matplotlib list!)" % (label_namer, func.__name__),
                        RuntimeWarning, stacklevel=2)
            return func(ax, *args, **kwargs)

        inner.__doc__ = _add_data_doc(inner.__doc__,
                                      replace_names, replace_all_args)
        inner.__signature__ = new_sig
        return inner

    return param

_log.debug('matplotlib version %s', __version__)
_log.debug('interactive is %s', is_interactive())
_log.debug('platform is %s', sys.platform)
_log.debug('loaded modules: %s', list(sys.modules))