matplotlib.github.com/2.2.4/_modules/matplotlib/dates.html at main · matplotlib/matplotlib.github.com

History

1978 lines (1586 loc) · 224 KB

Raw

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

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

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

<head>

<title>matplotlib.dates — Matplotlib 2.2.4 documentation</title>

type="text/css" />

type="text/css" />

var DOCUMENTATION_OPTIONS = {

URL_ROOT: '../../',

VERSION: '2.2.4',

COLLAPSE_INDEX: false,

FILE_SUFFIX: '.html',

HAS_SOURCE: true,

SOURCELINK_SUFFIX: '.txt'

};

</script>

title="Search within Matplotlib 2.2.4 documentation"

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

</head>

<body>

<div id="unreleased-message"> You are reading an old version of the documentation (v2.2.4). 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 2.2.4</div>

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

</div>

<h3>Navigation</h3>

<ul>

<a href="../../genindex.html" title="General Index"

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

<a href="../../py-modindex.html" title="Python Module Index"

>modules</a> |</li>

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

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

<li><a href="../../api/pyplot_summary.html">pyplot</a>| </li>

<li><a href="../index.html" >Module code</a> »</li>

<li><a href="../matplotlib.html" accesskey="U">matplotlib</a> »</li>

</ul>

</div>

<h3>Quick search</h3>

</form>

</div>

<h3>Related Topics</h3>

<ul>

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

<li><a href="../index.html">Module code</a><ul>

<li><a href="../matplotlib.html">matplotlib</a><ul>

</ul></li>

</ul>

</div>

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

"""

Matplotlib provides sophisticated date plotting capabilities, standing on the

shoulders of python :mod:`datetime`, the add-on modules :mod:`pytz` and

:mod:`dateutil`.

.. _date-format:

Matplotlib date format

----------------------

Matplotlib represents dates using floating point numbers specifying the number

of days since 0001-01-01 UTC, plus 1. For example, 0001-01-01, 06:00 is 1.25,

not 0.25. Values < 1, i.e. dates before 0001-01-01 UTC are not supported.

There are a number of helper functions to convert between :mod:`datetime`

objects and Matplotlib dates:

.. currentmodule:: matplotlib.dates

.. autosummary::

:nosignatures:

date2num

num2date

num2timedelta

epoch2num

num2epoch

mx2num

drange

.. note::

Like Python's datetime, mpl uses the Gregorian calendar for all

conversions between dates and floating point numbers. This practice

is not universal, and calendar differences can cause confusing

differences between what Python and mpl give as the number of days

since 0001-01-01 and what other software and databases yield. For

example, the US Naval Observatory uses a calendar that switches

from Julian to Gregorian in October, 1582. Hence, using their

calculator, the number of days between 0001-01-01 and 2006-04-01 is

732403, whereas using the Gregorian calendar via the datetime

module we find::

In [1]: date(2006, 4, 1).toordinal() - date(1, 1, 1).toordinal()

Out[1]: 732401

All the Matplotlib date converters, tickers and formatters are timezone aware.

If no explicit timezone is provided, the rcParam ``timezone`` is assumend. If

you want to use a custom time zone, pass a :class:`pytz.timezone` instance

with the tz keyword argument to :func:`num2date`, :func:`.plot_date`, and any

custom date tickers or locators you create.

See `pytz <http://pythonhosted.org/pytz/>`_ for information on :mod:`pytz` and

timezone handling.

A wide range of specific and general purpose date tick locators and

formatters are provided in this module. See

:mod:`matplotlib.ticker` for general information on tick locators

and formatters. These are described below.

The `dateutil module <https://dateutil.readthedocs.io/en/stable/>`_ provides

additional code to handle date ticking, making it easy to place ticks

on any kinds of dates. See examples below.

Date tickers

------------

Most of the date tickers can locate single or multiple values. For

example::

# import constants for the days of the week

from matplotlib.dates import MO, TU, WE, TH, FR, SA, SU

# tick on mondays every week

loc = WeekdayLocator(byweekday=MO, tz=tz)

# tick on mondays and saturdays

loc = WeekdayLocator(byweekday=(MO, SA))

In addition, most of the constructors take an interval argument::

# tick on mondays every second week

loc = WeekdayLocator(byweekday=MO, interval=2)

The rrule locator allows completely general date ticking::

# tick every 5th easter

rule = rrulewrapper(YEARLY, byeaster=1, interval=5)

loc = RRuleLocator(rule)

Here are all the date tickers:

* :class:`MicrosecondLocator`: locate microseconds

* :class:`SecondLocator`: locate seconds

* :class:`MinuteLocator`: locate minutes

* :class:`HourLocator`: locate hours

* :class:`DayLocator`: locate specified days of the month

* :class:`WeekdayLocator`: Locate days of the week, e.g., MO, TU

* :class:`MonthLocator`: locate months, e.g., 7 for july

* :class:`YearLocator`: locate years that are multiples of base

* :class:`RRuleLocator`: locate using a

:class:`matplotlib.dates.rrulewrapper`. The

:class:`rrulewrapper` is a simple wrapper around a

:class:`dateutil.rrule` (`dateutil

<https://dateutil.readthedocs.io/en/stable/>`_) which allow almost

arbitrary date tick specifications. See `rrule example

<../gallery/ticks_and_spines/date_demo_rrule.html>`_.

* :class:`AutoDateLocator`: On autoscale, this class picks the best

:class:`DateLocator` (e.g., :class:`RRuleLocator`)

to set the view limits and the tick

locations. If called with ``interval_multiples=True`` it will

make ticks line up with sensible multiples of the tick intervals. E.g.

if the interval is 4 hours, it will pick hours 0, 4, 8, etc as ticks.

This behaviour is not guaranteed by default.

Date formatters

---------------

Here all all the date formatters:

* :class:`AutoDateFormatter`: attempts to figure out the best format

to use. This is most useful when used with the :class:`AutoDateLocator`.

* :class:`DateFormatter`: use :func:`strftime` format strings

* :class:`IndexDateFormatter`: date plots with implicit *x*

indexing.

"""

from __future__ import (absolute_import, division, print_function,

unicode_literals)

import six

from six.moves import zip

import re

import time

import math

import datetime

import functools

import warnings

import logging

from dateutil.rrule import (rrule, MO, TU, WE, TH, FR, SA, SU, YEARLY,

MONTHLY, WEEKLY, DAILY, HOURLY, MINUTELY,

SECONDLY)

from dateutil.relativedelta import relativedelta

import dateutil.parser

import logging

import numpy as np

import matplotlib

from matplotlib import rcParams

import matplotlib.units as units

import matplotlib.cbook as cbook

import matplotlib.ticker as ticker

_log = logging.getLogger(__name__)

__all__ = ('date2num', 'num2date', 'num2timedelta', 'drange', 'epoch2num',

'num2epoch', 'mx2num', 'DateFormatter',

'IndexDateFormatter', 'AutoDateFormatter', 'DateLocator',

'RRuleLocator', 'AutoDateLocator', 'YearLocator',

'MonthLocator', 'WeekdayLocator',

'DayLocator', 'HourLocator', 'MinuteLocator',

'SecondLocator', 'MicrosecondLocator',

'rrule', 'MO', 'TU', 'WE', 'TH', 'FR', 'SA', 'SU',

'YEARLY', 'MONTHLY', 'WEEKLY', 'DAILY',

'HOURLY', 'MINUTELY', 'SECONDLY', 'MICROSECONDLY', 'relativedelta',

'seconds', 'minutes', 'hours', 'weeks')

# Make a simple UTC instance so we don't always have to import

# pytz. From the python datetime library docs:

class _UTC(datetime.tzinfo):

"""UTC"""

def utcoffset(self, dt):

return datetime.timedelta(0)

def tzname(self, dt):

return str("UTC")

def dst(self, dt):

return datetime.timedelta(0)

UTC = _UTC()

def _get_rc_timezone():

"""

Retrieve the preferred timeszone from the rcParams dictionary.

"""

s = matplotlib.rcParams['timezone']

if s == 'UTC':

return UTC

import pytz

return pytz.timezone(s)

"""

Time-related constants.

"""

EPOCH_OFFSET = float(datetime.datetime(1970, 1, 1).toordinal())

JULIAN_OFFSET = 1721424.5 # Julian date at 0001-01-01

MICROSECONDLY = SECONDLY + 1

HOURS_PER_DAY = 24.

MIN_PER_HOUR = 60.

SEC_PER_MIN = 60.

MONTHS_PER_YEAR = 12.

DAYS_PER_WEEK = 7.

DAYS_PER_MONTH = 30.

DAYS_PER_YEAR = 365.0

MINUTES_PER_DAY = MIN_PER_HOUR * HOURS_PER_DAY

SEC_PER_HOUR = SEC_PER_MIN * MIN_PER_HOUR

SEC_PER_DAY = SEC_PER_HOUR * HOURS_PER_DAY

SEC_PER_WEEK = SEC_PER_DAY * DAYS_PER_WEEK

MUSECONDS_PER_DAY = 1e6 * SEC_PER_DAY

MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY, SUNDAY = (

MO, TU, WE, TH, FR, SA, SU)

WEEKDAYS = (MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY, SUNDAY)

def _to_ordinalf(dt):

"""

Convert :mod:`datetime` or :mod:`date` to the Gregorian date as UTC float

days, preserving hours, minutes, seconds and microseconds. Return value

is a :func:`float`.

"""

# Convert to UTC

tzi = getattr(dt, 'tzinfo', None)

if tzi is not None:

dt = dt.astimezone(UTC)

tzi = UTC

base = float(dt.toordinal())

# If it's sufficiently datetime-like, it will have a `date()` method

cdate = getattr(dt, 'date', lambda: None)()

if cdate is not None:

# Get a datetime object at midnight UTC

midnight_time = datetime.time(0, tzinfo=tzi)

rdt = datetime.datetime.combine(cdate, midnight_time)

# Append the seconds as a fraction of a day

base += (dt - rdt).total_seconds() / SEC_PER_DAY

return base

# a version of _to_ordinalf that can operate on numpy arrays

_to_ordinalf_np_vectorized = np.vectorize(_to_ordinalf)

def _dt64_to_ordinalf(d):

"""

Convert `numpy.datetime64` or an ndarray of those types to Gregorian

date as UTC float. Roundoff is via float64 precision. Practically:

microseconds for dates between 290301 BC, 294241 AD, milliseconds for

larger dates (see `numpy.datetime64`). Nanoseconds aren't possible

because we do times compared to ``0001-01-01T00:00:00`` (plus one day).

"""

# the "extra" ensures that we at least allow the dynamic range out to

# seconds. That should get out to +/-2e11 years.

extra = d - d.astype('datetime64[s]')

extra = extra.astype('timedelta64[ns]')

t0 = np.datetime64('0001-01-01T00:00:00').astype('datetime64[s]')

dt = (d.astype('datetime64[s]') - t0).astype(np.float64)

dt += extra.astype(np.float64) / 1.0e9

dt = dt / SEC_PER_DAY + 1.0

NaT_int = np.datetime64('NaT').astype(np.int64)

d_int = d.astype(np.int64)

try:

dt[d_int == NaT_int] = np.nan

except TypeError:

if d_int == NaT_int:

dt = np.nan

return dt

def _from_ordinalf(x, tz=None):

"""

Convert Gregorian float of the date, preserving hours, minutes,

seconds and microseconds. Return value is a `.datetime`.

The input date *x* is a float in ordinal days at UTC, and the output will

be the specified `.datetime` object corresponding to that time in

timezone *tz*, or if *tz* is ``None``, in the timezone specified in

:rc:`timezone`.

"""

if tz is None:

tz = _get_rc_timezone()

ix, remainder = divmod(x, 1)

ix = int(ix)

if ix < 1:

raise ValueError('Cannot convert {} to a date. This often happens if '

'non-datetime values are passed to an axis that '

'expects datetime objects.'.format(ix))

dt = datetime.datetime.fromordinal(ix).replace(tzinfo=UTC)

# Since the input date `x` float is unable to preserve microsecond

# precision of time representation in non-antique years, the

# resulting datetime is rounded to the nearest multiple of

# `musec_prec`. A value of 20 is appropriate for current dates.

musec_prec = 20

remainder_musec = int(round(remainder * MUSECONDS_PER_DAY / musec_prec)

* musec_prec)

# For people trying to plot with full microsecond precision, enable

# an early-year workaround

if x < 30 * 365:

# add hours, minutes, seconds, microseconds

dt += datetime.timedelta(microseconds=remainder_musec)

return dt.astimezone(tz)

# a version of _from_ordinalf that can operate on numpy arrays

_from_ordinalf_np_vectorized = np.vectorize(_from_ordinalf)

class strpdate2num(object):

"""

Use this class to parse date strings to matplotlib datenums when

you know the date format string of the date you are parsing.

"""

def __init__(self, fmt):

""" fmt: any valid strptime format is supported """

self.fmt = fmt

def __call__(self, s):

"""s : string to be converted

return value: a date2num float

"""

return date2num(datetime.datetime(*time.strptime(s, self.fmt)[:6]))

class bytespdate2num(strpdate2num):

"""

Use this class to parse date strings to matplotlib datenums when

you know the date format string of the date you are parsing. See

:file:`examples/misc/load_converter.py`.

"""

def __init__(self, fmt, encoding='utf-8'):

"""

Args:

fmt: any valid strptime format is supported

encoding: encoding to use on byte input (default: 'utf-8')

"""

super(bytespdate2num, self).__init__(fmt)

self.encoding = encoding

def __call__(self, b):

"""

Args:

b: byte input to be converted

Returns:

A date2num float

"""

s = b.decode(self.encoding)

return super(bytespdate2num, self).__call__(s)

# a version of dateutil.parser.parse that can operate on nump0y arrays

_dateutil_parser_parse_np_vectorized = np.vectorize(dateutil.parser.parse)

def datestr2num(d, default=None):

"""

Convert a date string to a datenum using

:func:`dateutil.parser.parse`.

Parameters

----------

d : string or sequence of strings

The dates to convert.

default : datetime instance, optional

The default date to use when fields are missing in *d*.

"""

if isinstance(d, six.string_types):

dt = dateutil.parser.parse(d, default=default)

return date2num(dt)

else:

if default is not None:

d = [dateutil.parser.parse(s, default=default) for s in d]

d = np.asarray(d)

if not d.size:

return d

return date2num(_dateutil_parser_parse_np_vectorized(d))

<div class="viewcode-block" id="date2num"><a class="viewcode-back" href="../../api/dates_api.html#matplotlib.dates.date2num">[docs]</a>def date2num(d):

"""

Convert datetime objects to Matplotlib dates.

Parameters

----------

d : `datetime.datetime` or `numpy.datetime64` or sequences of these

Returns

-------

float or sequence of floats

Number of days (fraction part represents hours, minutes, seconds, ms)

since 0001-01-01 00:00:00 UTC, plus one.

Notes

-----

The addition of one here is a historical artifact. Also, note that the

Gregorian calendar is assumed; this is not universal practice.

For details see the module docstring.

"""

if hasattr(d, "values"):

# this unpacks pandas series or dataframes...

d = d.values

if ((isinstance(d, np.ndarray) and np.issubdtype(d.dtype, np.datetime64))

or isinstance(d, np.datetime64)):

return _dt64_to_ordinalf(d)

if not cbook.iterable(d):

return _to_ordinalf(d)

else:

if not d.size:

return d

return _to_ordinalf_np_vectorized(d)</div>

def julian2num(j):

"""

Convert a Julian date (or sequence) to a Matplotlib date (or sequence).

Parameters

----------

j : float or sequence of floats

Julian date(s)

Returns

-------

float or sequence of floats

Matplotlib date(s)

"""

if cbook.iterable(j):

j = np.asarray(j)

return j - JULIAN_OFFSET

def num2julian(n):

"""

Convert a Matplotlib date (or sequence) to a Julian date (or sequence).

Parameters

----------

n : float or sequence of floats

Matplotlib date(s)

Returns

-------

float or sequence of floats

Julian date(s)

"""

if cbook.iterable(n):

n = np.asarray(n)

return n + JULIAN_OFFSET

<div class="viewcode-block" id="num2date"><a class="viewcode-back" href="../../api/dates_api.html#matplotlib.dates.num2date">[docs]</a>def num2date(x, tz=None):

"""

Convert Matplotlib dates to `~datetime.datetime` objects.

Parameters

----------

x : float or sequence of floats

Number of days (fraction part represents hours, minutes, seconds)

since 0001-01-01 00:00:00 UTC, plus one.

tz : string, optional

Timezone of *x* (defaults to rcparams ``timezone``).

Returns

-------

`~datetime.datetime` or sequence of `~datetime.datetime`

Dates are returned in timezone *tz*.

If *x* is a sequence, a sequence of :class:`datetime` objects will

be returned.

Notes

-----

The addition of one here is a historical artifact. Also, note that the

Gregorian calendar is assumed; this is not universal practice.

For details, see the module docstring.

"""

if tz is None:

tz = _get_rc_timezone()

return _from_ordinalf(x, tz)

else:

x = np.asarray(x)

if not x.size:

return x

return _from_ordinalf_np_vectorized(x, tz).tolist()</div>

def _ordinalf_to_timedelta(x):

return datetime.timedelta(days=x)

_ordinalf_to_timedelta_np_vectorized = np.vectorize(_ordinalf_to_timedelta)

<div class="viewcode-block" id="num2timedelta"><a class="viewcode-back" href="../../api/dates_api.html#matplotlib.dates.num2timedelta">[docs]</a>def num2timedelta(x):

"""

Convert number of days to a `~datetime.timedelta` object.

If *x* is a sequence, a sequence of `~datetime.timedelta` objects will

be returned.

Parameters

----------

x : float, sequence of floats

Number of days. The fraction part represents hours, minutes, seconds.

Returns

-------

`datetime.timedelta` or list[`datetime.timedelta`]

"""

return _ordinalf_to_timedelta(x)

else:

if not x.size:

return x

return _ordinalf_to_timedelta_np_vectorized(x).tolist()</div>

<div class="viewcode-block" id="drange"><a class="viewcode-back" href="../../api/dates_api.html#matplotlib.dates.drange">[docs]</a>def drange(dstart, dend, delta):

"""

Return a sequence of equally spaced Matplotlib dates.

The dates start at *dstart* and reach up to, but not including *dend*.

They are spaced by *delta*.

Parameters

----------

dstart, dend : `~datetime.datetime`

The date limits.

delta : `datetime.timedelta`

Spacing of the dates.

Returns

-------

drange : `numpy.array`

A list floats representing Matplotlib dates.

"""

f1 = date2num(dstart)

f2 = date2num(dend)

step = delta.total_seconds() / SEC_PER_DAY

# calculate the difference between dend and dstart in times of delta

num = int(np.ceil((f2 - f1) / step))

# calculate end of the interval which will be generated

dinterval_end = dstart + num * delta

# ensure, that an half open interval will be generated [dstart, dend)

if dinterval_end >= dend:

# if the endpoint is greated than dend, just subtract one delta

dinterval_end -= delta

num -= 1

f2 = date2num(dinterval_end) # new float-endpoint

return np.linspace(f1, f2, num + 1)</div>

### date tickers and formatters ###

<div class="viewcode-block" id="DateFormatter"><a class="viewcode-back" href="../../api/dates_api.html#matplotlib.dates.DateFormatter">[docs]</a>class DateFormatter(ticker.Formatter):

"""

Tick location is seconds since the epoch. Use a :func:`strftime`

format string.

Python only supports :mod:`datetime` :func:`strftime` formatting

for years greater than 1900. Thanks to Andrew Dalke, Dalke

Scientific Software who contributed the :func:`strftime` code

below to include dates earlier than this year.

"""

illegal_s = re.compile(r"((^|[^%])(%%)*%s)")

def __init__(self, fmt, tz=None):

"""

*fmt* is a :func:`strftime` format string; *tz* is the

:class:`tzinfo` instance.

"""

if tz is None:

tz = _get_rc_timezone()

self.fmt = fmt

self.tz = tz

def __call__(self, x, pos=0):

if x == 0:

raise ValueError('DateFormatter found a value of x=0, which is '

'an illegal date. This usually occurs because '

'you have not informed the axis that it is '

'plotting dates, e.g., with ax.xaxis_date()')

dt = num2date(x, self.tz)

return self.strftime(dt, self.fmt)

<div class="viewcode-block" id="DateFormatter.set_tzinfo"><a class="viewcode-back" href="../../api/dates_api.html#matplotlib.dates.DateFormatter.set_tzinfo">[docs]</a> def set_tzinfo(self, tz):

self.tz = tz</div>

def _replace_common_substr(self, s1, s2, sub1, sub2, replacement):

"""Helper function for replacing substrings sub1 and sub2

located at the same indexes in strings s1 and s2 respectively,

with the string replacement. It is expected that sub1 and sub2

have the same length. Returns the pair s1, s2 after the

substitutions.

"""

# Find common indexes of substrings sub1 in s1 and sub2 in s2

# and make substitutions inplace. Because this is inplace,

# it is okay if len(replacement) != len(sub1), len(sub2).

i = 0

while True:

j = s1.find(sub1, i)

if j == -1:

break

i = j + 1

if s2[j:j + len(sub2)] != sub2:

continue

s1 = s1[:j] + replacement + s1[j + len(sub1):]

s2 = s2[:j] + replacement + s2[j + len(sub2):]

return s1, s2

<div class="viewcode-block" id="DateFormatter.strftime_pre_1900"><a class="viewcode-back" href="../../api/dates_api.html#matplotlib.dates.DateFormatter.strftime_pre_1900">[docs]</a> def strftime_pre_1900(self, dt, fmt=None):

"""Call time.strftime for years before 1900 by rolling

forward a multiple of 28 years.

*fmt* is a :func:`strftime` format string.

Dalke: I hope I did this math right. Every 28 years the

calendar repeats, except through century leap years excepting

the 400 year leap years. But only if you're using the Gregorian

calendar.

"""

if fmt is None:

fmt = self.fmt

# Since python's time module's strftime implementation does not

# support %f microsecond (but the datetime module does), use a

# regular expression substitution to replace instances of %f.

# Note that this can be useful since python's floating-point

# precision representation for datetime causes precision to be

# more accurate closer to year 0 (around the year 2000, precision

# can be at 10s of microseconds).

fmt = re.sub(r'((^|[^%])(%%)*)%f',

r'\g<1>{0:06d}'.format(dt.microsecond), fmt)

year = dt.year

# For every non-leap year century, advance by

# 6 years to get into the 28-year repeat cycle

delta = 2000 - year

off = 6 * (delta // 100 + delta // 400)

year = year + off

# Move to between the years 1973 and 2000

year1 = year + ((2000 - year) // 28) * 28

year2 = year1 + 28

timetuple = dt.timetuple()

# Generate timestamp string for year and year+28

s1 = time.strftime(fmt, (year1,) + timetuple[1:])

s2 = time.strftime(fmt, (year2,) + timetuple[1:])

# Replace instances of respective years (both 2-digit and 4-digit)

# that are located at the same indexes of s1, s2 with dt's year.

# Note that C++'s strftime implementation does not use padded

# zeros or padded whitespace for %y or %Y for years before 100, but

# uses padded zeros for %x. (For example, try the runnable examples

# with .tm_year in the interval [-1900, -1800] on

# http://en.cppreference.com/w/c/chrono/strftime.) For ease of

# implementation, we always use padded zeros for %y, %Y, and %x.

s1, s2 = self._replace_common_substr(s1, s2,

"{0:04d}".format(year1),

"{0:02d}".format(year1 % 100),

"{0:02d}".format(year2 % 100),

"{0:02d}".format(dt.year % 100))

return cbook.unicode_safe(s1)</div>

<div class="viewcode-block" id="DateFormatter.strftime"><a class="viewcode-back" href="../../api/dates_api.html#matplotlib.dates.DateFormatter.strftime">[docs]</a> def strftime(self, dt, fmt=None):

"""

Refer to documentation for :meth:`datetime.datetime.strftime`

*fmt* is a :meth:`datetime.datetime.strftime` format string.

Warning: For years before 1900, depending upon the current

locale it is possible that the year displayed with %x might

be incorrect. For years before 100, %y and %Y will yield

zero-padded strings.

"""

if fmt is None:

fmt = self.fmt

fmt = self.illegal_s.sub(r"\1", fmt)

fmt = fmt.replace("%s", "s")

if dt.year >= 1900:

# Note: in python 3.3 this is okay for years >= 1000,

# refer to http://bugs.python.org/issue1777412

return cbook.unicode_safe(dt.strftime(fmt))

return self.strftime_pre_1900(dt, fmt)</div></div>

<div class="viewcode-block" id="IndexDateFormatter"><a class="viewcode-back" href="../../api/dates_api.html#matplotlib.dates.IndexDateFormatter">[docs]</a>class IndexDateFormatter(ticker.Formatter):

"""

Use with :class:`~matplotlib.ticker.IndexLocator` to cycle format

strings by index.

"""

def __init__(self, t, fmt, tz=None):

"""

*t* is a sequence of dates (floating point days). *fmt* is a

:func:`strftime` format string.

"""

if tz is None:

tz = _get_rc_timezone()

self.t = t

self.fmt = fmt

self.tz = tz

'Return the label for time *x* at position *pos*'

ind = int(np.round(x))

if ind >= len(self.t) or ind <= 0:

return ''

dt = num2date(self.t[ind], self.tz)

<div class="viewcode-block" id="AutoDateFormatter"><a class="viewcode-back" href="../../api/dates_api.html#matplotlib.dates.AutoDateFormatter">[docs]</a>class AutoDateFormatter(ticker.Formatter):

"""

This class attempts to figure out the best format to use. This is

most useful when used with the :class:`AutoDateLocator`.

The AutoDateFormatter has a scale dictionary that maps the scale

of the tick (the distance in days between one major tick) and a

format string. The default looks like this::

self.scaled = {

DAYS_PER_YEAR: rcParams['date.autoformat.year'],

DAYS_PER_MONTH: rcParams['date.autoformat.month'],

1.0: rcParams['date.autoformat.day'],

1. / HOURS_PER_DAY: rcParams['date.autoformat.hour'],

1. / (MINUTES_PER_DAY): rcParams['date.autoformat.minute'],

1. / (SEC_PER_DAY): rcParams['date.autoformat.second'],

1. / (MUSECONDS_PER_DAY): rcParams['date.autoformat.microsecond'],

}

The algorithm picks the key in the dictionary that is >= the

current scale and uses that format string. You can customize this

dictionary by doing::

>>> locator = AutoDateLocator()

>>> formatter = AutoDateFormatter(locator)

>>> formatter.scaled[1/(24.*60.)] = '%M:%S' # only show min and sec

A custom :class:`~matplotlib.ticker.FuncFormatter` can also be used.

The following example shows how to use a custom format function to strip

trailing zeros from decimal seconds and adds the date to the first

ticklabel::

>>> def my_format_function(x, pos=None):

... x = matplotlib.dates.num2date(x)

... if pos == 0:

... fmt = '%D %H:%M:%S.%f'

... else:

... fmt = '%H:%M:%S.%f'

... label = x.strftime(fmt)

... label = label.rstrip("0")

... label = label.rstrip(".")

... return label

>>> from matplotlib.ticker import FuncFormatter

>>> formatter.scaled[1/(24.*60.)] = FuncFormatter(my_format_function)

"""

# This can be improved by providing some user-level direction on

# how to choose the best format (precedence, etc...)

# Perhaps a 'struct' that has a field for each time-type where a

# zero would indicate "don't show" and a number would indicate

# "show" with some sort of priority. Same priorities could mean

# show all with the same priority.

# Or more simply, perhaps just a format string for each

# possibility...

def __init__(self, locator, tz=None, defaultfmt='%Y-%m-%d'):

"""

Autoformat the date labels. The default format is the one to use

if none of the values in ``self.scaled`` are greater than the unit

returned by ``locator._get_unit()``.

"""

self._locator = locator

self._tz = tz

self.defaultfmt = defaultfmt

self._formatter = DateFormatter(self.defaultfmt, tz)

self.scaled = {DAYS_PER_YEAR: rcParams['date.autoformatter.year'],

DAYS_PER_MONTH: rcParams['date.autoformatter.month'],

1.0: rcParams['date.autoformatter.day'],

1. / HOURS_PER_DAY: rcParams['date.autoformatter.hour'],

1. / (MINUTES_PER_DAY):

rcParams['date.autoformatter.minute'],

1. / (SEC_PER_DAY):

rcParams['date.autoformatter.second'],

1. / (MUSECONDS_PER_DAY):

rcParams['date.autoformatter.microsecond']}

locator_unit_scale = float(self._locator._get_unit())

# Pick the first scale which is greater than the locator unit.

fmt = next((fmt for scale, fmt in sorted(self.scaled.items())

if scale >= locator_unit_scale),

self.defaultfmt)

if isinstance(fmt, six.string_types):

self._formatter = DateFormatter(fmt, self._tz)

result = self._formatter(x, pos)

elif callable(fmt):

result = fmt(x, pos)

else:

raise TypeError('Unexpected type passed to {0!r}.'.format(self))

return result</div>

class rrulewrapper(object):

def __init__(self, freq, tzinfo=None, **kwargs):

kwargs['freq'] = freq

self._base_tzinfo = tzinfo

self._update_rrule(**kwargs)

def set(self, **kwargs):

self._construct.update(kwargs)

self._update_rrule(**self._construct)

View remainder of file in raw view

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

FilesExpand file tree

dates.html

Latest commit

History

dates.html

File metadata and controls