#!/usr/bin/env python3
"""
The constructor functions used to build class instances from simple shorthand arguments.
"""
# NOTE: These functions used to be in separate files like crs.py and
# ticker.py but makes more sense to group them together to ensure usage is
# consistent and so online documentation is easier to understand. Also in
# future version classes will not be imported into top-level namespace. This
# change will be easier to do with all constructor functions in separate file.
# NOTE: Used to include the raw variable names that define string keys as
# part of documentation, but this is redundant and pollutes the namespace.
# User should just inspect docstrings, use trial-error, or see online tables.
import os
import re
from functools import partial
from numbers import Number
import cycler
import matplotlib.colors as mcolors
import matplotlib.dates as mdates
import matplotlib.projections as mproj
import matplotlib.scale as mscale
import matplotlib.ticker as mticker
import numpy as np
from . import colors as pcolors
from . import crs as pcrs
from . import scale as pscale
from . import ticker as pticker
from .config import rc
from .internals import ic # noqa: F401
from .internals import _not_none, _pop_props, dependencies, warnings
from .utils import get_colors, to_hex, to_rgba
try:
from mpl_toolkits.basemap import Basemap
except ImportError:
Basemap = object
try:
import cartopy.crs as ccrs
import cartopy.mpl.ticker as cticker
from cartopy.crs import Projection
except ModuleNotFoundError:
Projection = ccrs = cticker = object
__all__ = [
'Proj',
'Locator',
'Formatter',
'Scale',
'Colormap',
'Norm',
'Cycle',
'Colors', # deprecated
]
# Color cycle constants
# TODO: Also automatically truncate the 'bright' end of colormaps
# when building color cycles from colormaps? Or add simple option.
DEFAULT_CYCLE_SAMPLES = 10
DEFAULT_CYCLE_LUMINANCE = 90
# Normalizer registry
NORMS = {
'none': mcolors.NoNorm,
'null': mcolors.NoNorm,
'div': pcolors.DivergingNorm,
'diverging': pcolors.DivergingNorm,
'segmented': pcolors.SegmentedNorm,
'segments': pcolors.SegmentedNorm,
'log': mcolors.LogNorm,
'linear': mcolors.Normalize,
'power': mcolors.PowerNorm,
'symlog': mcolors.SymLogNorm,
}
if hasattr(mcolors, 'TwoSlopeNorm'):
NORMS['twoslope'] = mcolors.TwoSlopeNorm
# Locator registry
LOCATORS = {
'none': mticker.NullLocator,
'null': mticker.NullLocator,
'auto': mticker.AutoLocator,
'log': mticker.LogLocator,
'maxn': mticker.MaxNLocator,
'linear': mticker.LinearLocator,
'multiple': mticker.MultipleLocator,
'fixed': mticker.FixedLocator,
'index': mticker.IndexLocator,
'symlog': mticker.SymmetricalLogLocator,
'logit': mticker.LogitLocator,
'minor': mticker.AutoMinorLocator,
'date': mdates.AutoDateLocator,
'microsecond': mdates.MicrosecondLocator,
'second': mdates.SecondLocator,
'minute': mdates.MinuteLocator,
'hour': mdates.HourLocator,
'day': mdates.DayLocator,
'weekday': mdates.WeekdayLocator,
'month': mdates.MonthLocator,
'year': mdates.YearLocator,
'lon': partial(pticker.LongitudeLocator, dms=False),
'lat': partial(pticker.LatitudeLocator, dms=False),
'deglon': partial(pticker.LongitudeLocator, dms=False),
'deglat': partial(pticker.LatitudeLocator, dms=False),
}
if dependencies._version_cartopy >= 0.18:
# NOTE: This only makes sense when paired with degree-minute-second formatter
LOCATORS['dms'] = partial(pticker.DegreeLocator, dms=True)
LOCATORS['dmslon'] = partial(pticker.LongitudeLocator, dms=True)
LOCATORS['dmslat'] = partial(pticker.LatitudeLocator, dms=True)
if hasattr(mproj.polar, 'ThetaLocator'):
LOCATORS['theta'] = mproj.polar.ThetaLocator
# Formatter registry
# NOTE: Critical to use SimpleFormatter for cardinal formatters rather than
# AutoFormatter because latter fails with Basemap formatting.
# NOTE: Define cartopy longitude/latitude formatters with dms=True because that
# is their distinguishing feature relative to proplot formatter.
FORMATTERS = { # note default LogFormatter uses ugly e+00 notation
'auto': pticker.AutoFormatter,
'frac': pticker.FracFormatter,
'sci': pticker.SciFormatter,
'sigfig': pticker.SigFigFormatter,
'simple': pticker.SimpleFormatter,
'date': mdates.AutoDateFormatter,
'datestr': mdates.DateFormatter,
'scalar': mticker.ScalarFormatter,
'none': mticker.NullFormatter,
'null': mticker.NullFormatter,
'func': mticker.FuncFormatter,
'strmethod': mticker.StrMethodFormatter,
'formatstr': mticker.FormatStrFormatter,
'log': mticker.LogFormatterSciNotation, # NOTE: this is subclass of Mathtext class
'logit': mticker.LogitFormatter,
'eng': mticker.EngFormatter,
'percent': mticker.PercentFormatter,
'index': pticker.IndexFormatter,
'e': partial(pticker.FracFormatter, symbol=r'$e$', number=np.e),
'pi': partial(pticker.FracFormatter, symbol=r'$\pi$', number=np.pi),
'tau': partial(pticker.FracFormatter, symbol=r'$\tau$', number=2 * np.pi),
'lat': partial(pticker.SimpleFormatter, negpos='SN'),
'lon': partial(pticker.SimpleFormatter, negpos='WE', wraprange=(-180, 180)),
'deg': partial(pticker.SimpleFormatter, suffix='\N{DEGREE SIGN}'),
'deglat': partial(pticker.SimpleFormatter, suffix='\N{DEGREE SIGN}', negpos='SN'),
'deglon': partial(pticker.SimpleFormatter, suffix='\N{DEGREE SIGN}', negpos='WE', wraprange=(-180, 180)), # noqa: E501
'math': mticker.LogFormatterMathtext, # deprecated (use SciNotation subclass)
}
if dependencies._version_cartopy >= 0.18:
# NOTE: Will raise error when you try to use these without cartopy >= 0.18
FORMATTERS['dms'] = partial(pticker.DegreeFormatter, dms=True)
FORMATTERS['dmslon'] = partial(pticker.LongitudeFormatter, dms=True)
FORMATTERS['dmslat'] = partial(pticker.LatitudeFormatter, dms=True)
if hasattr(mproj.polar, 'ThetaFormatter'):
FORMATTERS['theta'] = mproj.polar.ThetaFormatter
if hasattr(mdates, 'ConciseDateFormatter'):
FORMATTERS['concise'] = mdates.ConciseDateFormatter
# Scale registry and presets
SCALES = mscale._scale_mapping
SCALE_PRESETS = {
'quadratic': ('power', 2,),
'cubic': ('power', 3,),
'quartic': ('power', 4,),
'height': ('exp', np.e, -1 / 7, 1013.25, True),
'pressure': ('exp', np.e, -1 / 7, 1013.25, False),
'db': ('exp', 10, 1, 0.1, True),
'idb': ('exp', 10, 1, 0.1, False),
'np': ('exp', np.e, 1, 1, True),
'inp': ('exp', np.e, 1, 1, False),
}
mscale.register_scale(pscale.CutoffScale)
mscale.register_scale(pscale.ExpScale)
mscale.register_scale(pscale.FuncScale)
mscale.register_scale(pscale.InverseScale)
mscale.register_scale(pscale.LogScale)
mscale.register_scale(pscale.LinearScale)
mscale.register_scale(pscale.LogitScale)
mscale.register_scale(pscale.MercatorLatitudeScale)
mscale.register_scale(pscale.PowerScale)
mscale.register_scale(pscale.SineLatitudeScale)
mscale.register_scale(pscale.SymmetricalLogScale)
# Cartopy projection registry and default basemap keyword args
# NOTE: Normally basemap raises error if you omit keyword args
PROJ_ALIASES = { # aliases to basemap naming conventions
'eqc': 'cyl',
'pcarree': 'cyl',
}
PROJ_ALIASES_KW = { # use PROJ shorthands instead of verbose cartopy names
'lat_0': 'central_latitude',
'lon_0': 'central_longitude',
'lat_min': 'min_latitude',
'lat_max': 'max_latitude',
}
PROJ_DEFAULTS = {
'geos': {'lon_0': 0},
'eck4': {'lon_0': 0},
'moll': {'lon_0': 0},
'hammer': {'lon_0': 0},
'kav7': {'lon_0': 0},
'sinu': {'lon_0': 0},
'vandg': {'lon_0': 0},
'mbtfpq': {'lon_0': 0},
'robin': {'lon_0': 0},
'ortho': {'lon_0': 0, 'lat_0': 0},
'nsper': {'lon_0': 0, 'lat_0': 0},
'aea': {'lon_0': 0, 'lat_0': 90, 'width': 15000e3, 'height': 15000e3},
'eqdc': {'lon_0': 0, 'lat_0': 90, 'width': 15000e3, 'height': 15000e3},
'cass': {'lon_0': 0, 'lat_0': 90, 'width': 15000e3, 'height': 15000e3},
'gnom': {'lon_0': 0, 'lat_0': 90, 'width': 15000e3, 'height': 15000e3},
'poly': {'lon_0': 0, 'lat_0': 0, 'width': 10000e3, 'height': 10000e3},
'npaeqd': {'lon_0': 0, 'boundinglat': 10}, # NOTE: everything breaks if you
'nplaea': {'lon_0': 0, 'boundinglat': 10}, # try to set boundinglat to zero
'npstere': {'lon_0': 0, 'boundinglat': 10},
'spaeqd': {'lon_0': 0, 'boundinglat': -10},
'splaea': {'lon_0': 0, 'boundinglat': -10},
'spstere': {'lon_0': 0, 'boundinglat': -10},
'lcc': {
'lon_0': 0, 'lat_0': 40, 'lat_1': 35, 'lat_2': 45, # use cartopy defaults
'width': 20000e3, 'height': 15000e3
},
'tmerc': {
'lon_0': 0, 'lat_0': 0, 'width': 10000e3, 'height': 10000e3
},
'merc': {
'llcrnrlat': -80, 'urcrnrlat': 84, 'llcrnrlon': -180, 'urcrnrlon': 180
},
'omerc': {
'lat_0': 0, 'lon_0': 0, 'lat_1': -10, 'lat_2': 10,
'lon_1': 0, 'lon_2': 0, 'width': 10000e3, 'height': 10000e3
},
}
if ccrs is object:
PROJS = {}
else:
PROJS = {
'aitoff': pcrs.Aitoff,
'hammer': pcrs.Hammer,
'kav7': pcrs.KavrayskiyVII,
'wintri': pcrs.WinkelTripel,
'npgnom': pcrs.NorthPolarGnomonic,
'spgnom': pcrs.SouthPolarGnomonic,
'npaeqd': pcrs.NorthPolarAzimuthalEquidistant,
'spaeqd': pcrs.SouthPolarAzimuthalEquidistant,
'nplaea': pcrs.NorthPolarLambertAzimuthalEqualArea,
'splaea': pcrs.SouthPolarLambertAzimuthalEqualArea,
}
PROJS_MISSING = {
'aea': 'AlbersEqualArea',
'aeqd': 'AzimuthalEquidistant',
'cyl': 'PlateCarree', # only basemap name not matching PROJ
'eck1': 'EckertI',
'eck2': 'EckertII',
'eck3': 'EckertIII',
'eck4': 'EckertIV',
'eck5': 'EckertV',
'eck6': 'EckertVI',
'eqc': 'PlateCarree', # actual PROJ name
'eqdc': 'EquidistantConic',
'eqearth': 'EqualEarth', # better looking Robinson; not in basemap
'euro': 'EuroPP', # Europe; not in basemap or PROJ
'geos': 'Geostationary',
'gnom': 'Gnomonic',
'igh': 'InterruptedGoodeHomolosine', # not in basemap
'laea': 'LambertAzimuthalEqualArea',
'lcc': 'LambertConformal',
'lcyl': 'LambertCylindrical', # not in basemap or PROJ
'merc': 'Mercator',
'mill': 'Miller',
'moll': 'Mollweide',
'npstere': 'NorthPolarStereo', # np/sp stuff not in PROJ
'nsper': 'NearsidePerspective',
'ortho': 'Orthographic',
'osgb': 'OSGB', # UK; not in basemap or PROJ
'osni': 'OSNI', # Ireland; not in basemap or PROJ
'pcarree': 'PlateCarree', # common alternate name
'robin': 'Robinson',
'rotpole': 'RotatedPole',
'sinu': 'Sinusoidal',
'spstere': 'SouthPolarStereo',
'stere': 'Stereographic',
'tmerc': 'TransverseMercator',
'utm': 'UTM', # not in basemap
}
for _key, _cls in tuple(PROJS_MISSING.items()):
if hasattr(ccrs, _cls):
PROJS[_key] = getattr(ccrs, _cls)
del PROJS_MISSING[_key]
if PROJS_MISSING:
warnings._warn_proplot(
'The following cartopy projection(s) are unavailable: '
+ ', '.join(map(repr, PROJS_MISSING))
+ ' . Please consider updating cartopy.'
)
PROJS_TABLE = (
'The known cartopy projection classes are:\n'
+ '\n'.join(
' ' + key + ' ' * (max(map(len, PROJS)) - len(key) + 10) + cls.__name__
for key, cls in PROJS.items()
)
)
# Geographic feature properties
FEATURES_CARTOPY = { # positional arguments passed to NaturalEarthFeature
'land': ('physical', 'land'),
'ocean': ('physical', 'ocean'),
'lakes': ('physical', 'lakes'),
'coast': ('physical', 'coastline'),
'rivers': ('physical', 'rivers_lake_centerlines'),
'borders': ('cultural', 'admin_0_boundary_lines_land'),
'innerborders': ('cultural', 'admin_1_states_provinces_lakes'),
}
FEATURES_BASEMAP = { # names of relevant basemap methods
'land': 'fillcontinents',
'coast': 'drawcoastlines',
'rivers': 'drawrivers',
'borders': 'drawcountries',
'innerborders': 'drawstates',
}
# Resolution names
# NOTE: Maximum basemap resolutions are much finer than cartopy
RESOS_CARTOPY = {
'lo': '110m',
'med': '50m',
'hi': '10m',
'x-hi': '10m', # extra high
'xx-hi': '10m', # extra extra high
}
RESOS_BASEMAP = {
'lo': 'c', # coarse
'med': 'l',
'hi': 'i', # intermediate
'x-hi': 'h',
'xx-hi': 'f', # fine
}
def _modify_colormap(cmap, *, cut, left, right, reverse, shift, alpha, samples):
"""
Modify colormap using a variety of methods.
"""
if cut is not None or left is not None or right is not None:
if isinstance(cmap, pcolors.DiscreteColormap):
if cut is not None:
warnings._warn_proplot(
"Invalid argument 'cut' for ListedColormap. Ignoring."
)
cmap = cmap.truncate(left=left, right=right)
else:
cmap = cmap.cut(cut, left=left, right=right)
if reverse:
cmap = cmap.reversed()
if shift is not None:
cmap = cmap.shifted(shift)
if alpha is not None:
cmap = cmap.copy(alpha=alpha)
if samples is not None:
if isinstance(cmap, pcolors.DiscreteColormap):
cmap = cmap.copy(N=samples)
else:
cmap = cmap.to_discrete(samples)
return cmap
[docs]@warnings._rename_kwargs(
'0.8', fade='saturation', shade='luminance', to_listed='discrete'
)
def Colormap(
*args, name=None, listmode='perceptual', filemode='continuous', discrete=False,
cycle=None, save=False, save_kw=None, **kwargs
):
"""
Generate, retrieve, modify, and/or merge instances of
`~proplot.colors.PerceptualColormap`,
`~proplot.colors.ContinuousColormap`, and
`~proplot.colors.DiscreteColormap`.
Parameters
----------
*args : colormap-spec
Positional arguments that individually generate colormaps. If more
than one argument is passed, the resulting colormaps are *merged* with
`~proplot.colors.ContinuousColormap.append`
or `~proplot.colors.DiscreteColormap.append`.
The arguments are interpreted as follows:
* If a registered colormap name, that colormap instance is looked up.
If colormap instance is a native matplotlib colormap class, it is
converted to a proplot colormap class.
* If a filename string with valid extension, the colormap data
is loaded with `proplot.colors.ContinuousColormap.from_file` or
`proplot.colors.DiscreteColormap.from_file` depending on the value of
`filemode` (see below). Default behavior is to load a
`~proplot.colors.ContinuousColormap`.
* If RGB tuple or color string, a `~proplot.colors.PerceptualColormap`
is generated with `~proplot.colors.PerceptualColormap.from_color`.
If the string ends in ``'_r'``, the monochromatic map will be
*reversed*, i.e. will go from dark to light instead of light to dark.
* If sequence of RGB tuples or color strings, a
`~proplot.colors.DiscreteColormap`, `~proplot.colors.PerceptualColormap`,
or `~proplot.colors.ContinuousColormap` is generated depending on
the value of `listmode` (see below). Default behavior is to generate a
`~proplot.colors.PerceptualColormap`.
* If dictionary, a `~proplot.colors.PerceptualColormap` is
generated with `~proplot.colors.PerceptualColormap.from_hsl`.
The dictionary should contain the keys ``'hue'``, ``'saturation'``,
``'luminance'``, and optionally ``'alpha'``, or their aliases (see below).
name : str, optional
Name under which the final colormap is registered. It can
then be reused by passing ``cmap='name'`` to plotting
functions. Names with leading underscores are ignored.
filemode : {'perceptual', 'continuous', 'discrete'}, optional
Controls how colormaps are generated when you input list(s) of colors.
The options are as follows:
* If ``'perceptual'`` or ``'continuous'``, a colormap is generated using
`~proplot.colors.ContinuousColormap.from_file`. The resulting
colormap may be a `~proplot.colors.ContinuousColormap` or
`~proplot.colors.PerceptualColormap` depending on the data file.
* If ``'discrete'``, a `~proplot.colors.DiscreteColormap` is generated
using `~proplot.colors.ContinuousColormap.from_file`.
Default is ``'continuous'`` when calling `Colormap` directly and
``'discrete'`` when `Colormap` is called by `Cycle`.
listmode : {'perceptual', 'continuous', 'discrete'}, optional
Controls how colormaps are generated when you input sequence(s)
of colors. The options are as follows:
* If ``'perceptual'``, a `~proplot.colors.PerceptualColormap`
is generated with `~proplot.colors.PerceptualColormap.from_list`.
* If ``'continuous'``, a `~proplot.colors.ContinuousColormap` is
generated with `~proplot.colors.ContinuousColormap.from_list`.
* If ``'discrete'``, a `~proplot.colors.DiscreteColormap` is generated
by simply passing the colors to the class.
Default is ``'perceptual'`` when calling `Colormap` directly and
``'discrete'`` when `Colormap` is called by `Cycle`.
samples : int or sequence of int, optional
For `~proplot.colors.ContinuousColormap`\\ s, this is used to
generate `~proplot.colors.DiscreteColormap`\\ s with
`~proplot.colors.ContinuousColormap.to_discrete`. For
`~proplot.colors.DiscreteColormap`\\ s, this is used to updates the
number of colors in the cycle. If `samples` is integer, it applies
to the final *merged* colormap. If it is a sequence of integers,
it applies to each input colormap individually.
discrete : bool, optional
If ``True``, when the final colormap is a
`~proplot.colors.DiscreteColormap`, we leave it alone, but when it is a
`~proplot.colors.ContinuousColormap`, we always call
`~proplot.colors.ContinuousColormap.to_discrete` with a
default `samples` value of ``10``. This argument is not
necessary if you provide the `samples` argument.
left, right : float or sequence of float, optional
Truncate the left or right edges of the colormap.
Passed to `~proplot.colors.ContinuousColormap.truncate`.
If float, these apply to the final *merged* colormap. If sequence
of float, these apply to each input colormap individually.
cut : float or sequence of float, optional
Cut out the center of the colormap. Passed to
`~proplot.colors.ContinuousColormap.cut`. If float,
this applies to the final *merged* colormap. If sequence of
float, these apply to each input colormap individually.
reverse : bool or sequence of bool, optional
Reverse the colormap. Passed to
`~proplot.colors.ContinuousColormap.reversed`. If
float, this applies to the final *merged* colormap. If
sequence of float, these apply to each input colormap individually.
shift : float or sequence of float, optional
Cyclically shift the colormap.
Passed to `~proplot.colors.ContinuousColormap.shifted`.
If float, this applies to the final *merged* colormap. If sequence
of float, these apply to each input colormap individually.
a
Shorthand for `alpha`.
alpha : float or color-spec or sequence, optional
The opacity of the colormap or the opacity gradation. Passed to
`proplot.colors.ContinuousColormap.set_alpha`
or `proplot.colors.DiscreteColormap.set_alpha`. If float, this applies
to the final *merged* colormap. If sequence of float, these apply to
each colormap individually.
h, s, l, c
Shorthands for `hue`, `luminance`, `saturation`, and `chroma`.
hue, saturation, luminance : float or color-spec or sequence, optional
The channel value(s) used to generate colormaps with
`~proplot.colors.PerceptualColormap.from_hsl` and
`~proplot.colors.PerceptualColormap.from_color`.
* If you provided no positional arguments, these are used to create
an arbitrary perceptually uniform colormap with
`~proplot.colors.PerceptualColormap.from_hsl`. This
is an alternative to passing a dictionary as a positional argument
with `hue`, `saturation`, and `luminance` as dictionary keys (see `args`).
* If you did provide positional arguments, and any of them are
color specifications, these control the look of monochromatic colormaps
generated with `~proplot.colors.PerceptualColormap.from_color`.
To use different values for each colormap, pass a sequence of floats
instead of a single float. Note the default `luminance` is ``90`` if
`discrete` is ``True`` and ``100`` otherwise.
chroma
Alias for `saturation`.
cycle : str, optional
The registered cycle name used to interpret cycle color strings
like ``'C0'`` and ``'C2'``. Default is from the active property
cycler. This lets you make monochromatic colormaps using
colors selected from arbitrary property cycles.
save : bool, optional
Whether to call the colormap/color cycle save method, i.e.
`proplot.colors.ContinuousColormap.save` or
`proplot.colors.DiscreteColormap.save`.
save_kw : dict-like, optional
Ignored if `save` is ``False``. Passed to the colormap/color cycle
save method, i.e. `proplot.colors.ContinuousColormap.save` or
`proplot.colors.DiscreteColormap.save`.
Other parameters
----------------
**kwargs
Passed to `proplot.colors.ContinuousColormap.copy`,
`proplot.colors.PerceptualColormap.copy`, or
`proplot.colors.DiscreteColormap.copy`.
Returns
-------
`~matplotlib.colors.Colormap`
A `~proplot.colors.ContinuousColormap` or
`~proplot.colors.DiscreteColormap` instance.
See also
--------
matplotlib.colors.Colormap
matplotlib.colors.LinearSegmentedColormap
matplotlib.colors.ListedColormap
Norm
Cycle
proplot.utils.get_colors
"""
# Helper function
# NOTE: Very careful here! Try to support common use cases. For example
# adding opacity gradations to colormaps with Colormap('cmap', alpha=(0.5, 1))
# or sampling maps with Colormap('cmap', samples=np.linspace(0, 1, 11)) should
# be allowable.
# If *args is singleton try to preserve it.
def _pop_modification(key):
value = kwargs.pop(key, None)
if not np.iterable(value) or isinstance(value, str):
values = (None,) * len(args)
elif len(args) == len(value):
values, value = tuple(value), None
elif len(args) == 1: # e.g. Colormap('cmap', alpha=(0.5, 1))
values = (None,)
else:
raise ValueError(
f'Got {len(args)} colormap-specs '
f'but {len(value)} values for {key!r}.'
)
return value, values
# Parse keyword args that can apply to the merged colormap or each one
hsla = _pop_props(kwargs, 'hsla')
if not args and hsla.keys() - {'alpha'}:
args = (hsla,)
else:
kwargs.update(hsla)
default_luminance = kwargs.pop('default_luminance', None) # used internally
cut, cuts = _pop_modification('cut')
left, lefts = _pop_modification('left')
right, rights = _pop_modification('right')
shift, shifts = _pop_modification('shift')
reverse, reverses = _pop_modification('reverse')
samples, sampless = _pop_modification('samples')
alpha, alphas = _pop_modification('alpha')
luminance, luminances = _pop_modification('luminance')
saturation, saturations = _pop_modification('saturation')
if luminance is not None:
luminances = (luminance,) * len(args)
if saturation is not None:
saturations = (saturation,) * len(args)
# Issue warnings and errors
if not args:
raise ValueError(
'Colormap() requires either positional arguments or '
"'hue', 'chroma', 'saturation', and/or 'luminance' keywords."
)
deprecated = {'listed': 'discrete', 'linear': 'continuous'}
if listmode in deprecated:
oldmode, listmode = listmode, deprecated[listmode]
warnings._warn_proplot(
f'Please use listmode={listmode!r} instead of listmode={oldmode!r}.'
'Option was renamed in v0.8 and will be removed in a future relase.'
)
options = {'discrete', 'continuous', 'perceptual'}
for key, mode in zip(('listmode', 'filemode'), (listmode, filemode)):
if mode not in options:
raise ValueError(
f'Invalid {key}={mode!r}. Options are: '
+ ', '.join(map(repr, options))
+ '.'
)
# Loop through colormaps
cmaps = []
for arg, icut, ileft, iright, ireverse, ishift, isamples, iluminance, isaturation, ialpha in zip( # noqa: E501
args, cuts, lefts, rights, reverses, shifts, sampless, luminances, saturations, alphas # noqa: E501
):
# Load registered colormaps and maps on file
# TODO: Document how 'listmode' also affects loaded files
if isinstance(arg, str):
if '.' in arg and os.path.isfile(arg):
if filemode == 'discrete':
arg = pcolors.DiscreteColormap.from_file(arg)
else:
arg = pcolors.ContinuousColormap.from_file(arg)
else:
try:
arg = pcolors._cmap_database[arg]
except KeyError:
pass
# Convert matplotlib colormaps to subclasses
if isinstance(arg, mcolors.Colormap):
cmap = pcolors._translate_cmap(arg)
# Dictionary of hue/sat/luminance values or 2-tuples
elif isinstance(arg, dict):
cmap = pcolors.PerceptualColormap.from_hsl(**arg)
# List of color tuples or color strings, i.e. iterable of iterables
elif (
not isinstance(arg, str) and np.iterable(arg)
and all(np.iterable(color) for color in arg)
):
if listmode == 'discrete':
cmap = pcolors.DiscreteColormap(arg)
elif listmode == 'continuous':
cmap = pcolors.ContinuousColormap.from_list(arg)
else:
cmap = pcolors.PerceptualColormap.from_list(arg)
# Monochrome colormap from input color
# NOTE: Do not print color names in error message. Too long to be useful.
else:
jreverse = isinstance(arg, str) and arg[-2:] == '_r'
if jreverse:
arg = arg[:-2]
try:
color = to_rgba(arg, cycle=cycle)
except (ValueError, TypeError):
message = f'Invalid colormap, color cycle, or color {arg!r}.'
if isinstance(arg, str) and arg[:1] != '#':
message += (
' Options include: '
+ ', '.join(sorted(map(repr, pcolors._cmap_database)))
+ '.'
)
raise ValueError(message) from None
iluminance = _not_none(iluminance, default_luminance)
cmap = pcolors.PerceptualColormap.from_color(
color, luminance=iluminance, saturation=isaturation
)
ireverse = _not_none(ireverse, False)
ireverse = ireverse ^ jreverse # xor
# Modify the colormap
cmap = _modify_colormap(
cmap, cut=icut, left=ileft, right=iright,
reverse=ireverse, shift=ishift, alpha=ialpha, samples=isamples,
)
cmaps.append(cmap)
# Merge the resulting colormaps
if len(cmaps) > 1: # more than one map and modify arbitrary properties
cmap = cmaps[0].append(*cmaps[1:], **kwargs)
else:
cmap = cmaps[0].copy(**kwargs)
# Modify the colormap
if discrete and isinstance(cmap, pcolors.ContinuousColormap): # noqa: E501
samples = _not_none(samples, DEFAULT_CYCLE_SAMPLES)
cmap = _modify_colormap(
cmap, cut=cut, left=left, right=right,
reverse=reverse, shift=shift, alpha=alpha, samples=samples
)
# Initialize
if not cmap._isinit:
cmap._init()
# Register the colormap
if name is None:
name = cmap.name # may have been modified by e.g. reversed()
else:
cmap.name = name
if not isinstance(name, str):
raise ValueError('Colormap name must be a string.')
pcolors._cmap_database[name] = cmap
# Save the colormap
if save:
save_kw = save_kw or {}
cmap.save(**save_kw)
return cmap
[docs]def Cycle(*args, N=None, samples=None, name=None, **kwargs):
"""
Generate and merge `~cycler.Cycler` instances in a variety of ways.
Parameters
----------
*args : colormap-spec or cycle-spec, optional
Positional arguments control the *colors* in the `~cycler.Cycler`
object. If zero arguments are passed, the single color ``'black'``
is used. If more than one argument is passed, the resulting cycles
are merged. Arguments are interpreted as follows:
* If a `~cycler.Cycler`, nothing more is done.
* If a sequence of RGB tuples or color strings, these colors are used.
* If a `~proplot.colors.DiscreteColormap`, colors from the ``colors``
attribute are used.
* If a string cycle name, that `~proplot.colors.DiscreteColormap`
is looked up and its ``colors`` are used.
* In all other cases, the argument is passed to `Colormap`, and
colors from the resulting `~proplot.colors.ContinuousColormap`
are used. See the `samples` argument.
If the last positional argument is numeric, it is used for the
`samples` keyword argument.
N
Shorthand for `samples`.
samples : float or sequence of float, optional
For `~proplot.colors.DiscreteColormap`\\ s, this is the number of
colors to select. For example, ``Cycle('538', 4)`` returns the first 4
colors of the ``'538'`` color cycle.
For `~proplot.colors.ContinuousColormap`\\ s, this is either a
sequence of sample coordinates used to draw colors from the colormap, or
an integer number of colors to draw. If the latter, the sample coordinates
are ``np.linspace(0, 1, samples)``. For example, ``Cycle('Reds', 5)``
divides the ``'Reds'`` colormap into five evenly spaced colors.
Other parameters
----------------
c, color, colors : sequence of color-spec, optional
A sequence of colors passed as keyword arguments. This is equivalent
to passing a sequence of colors as the first positional argument and is
included for consistency with `~matplotlib.axes.Axes.set_prop_cycle`.
If positional arguments were passed, the colors in this list are
appended to the colors resulting from the positional arguments.
lw, ls, d, a, m, ms, mew, mec, mfc
Shorthands for the below keywords.
linewidth, linestyle, dashes, alpha, marker, markersize, markeredgewidth, \
markeredgecolor, markerfacecolor : object or sequence of object, optional
Lists of `~matplotlib.lines.Line2D` properties that can be added to the
`~cycler.Cycler` instance. If the input was already a `~cycler.Cycler`,
these are added or appended to the existing cycle keys. If the lists have
unequal length, they are repeated to their least common multiple (note
that matplotlib throws an error in this case). For more info on cyclers see
`~matplotlib.axes.Axes.set_prop_cycle`. Also see the `line style reference \
<https://matplotlib.org/2.2.5/gallery/lines_bars_and_markers/line_styles_reference.html>`__,
the `marker reference \
<https://matplotlib.org/stable/gallery/lines_bars_and_markers/marker_reference.html>`__,
and the `custom dashes reference \
<https://matplotlib.org/stable/gallery/lines_bars_and_markers/line_demo_dash_control.html>`__.
linewidths, linestyles, dashes, alphas, markers, markersizes, markeredgewidths, \
markeredgecolors, markerfacecolors
Aliases for the above keywords.
**kwargs
If the input is not already a `~cycler.Cycler` instance, these are passed
to `Colormap` and used to build the `~proplot.colors.DiscreteColormap`
from which the cycler will draw its colors.
Returns
-------
`~cycler.Cycler`
A cycler instance that can be passed to
`~matplotlib.axes.Axes.set_prop_cycle`.
See also
--------
cycler.Cycler
Colormap
Norm
proplot.utils.get_colors
"""
# Parse keyword arguments that rotate through other properties
# besides color cycles.
props = _pop_props(kwargs, 'line')
samples = _not_none(samples=samples, N=N) # trigger Colormap default
for key, value in tuple(props.items()): # permit in-place modification
if value is None:
return
elif not np.iterable(value) or isinstance(value, str):
value = (value,)
props[key] = list(value) # ensure mutable list
# If args is non-empty, means we want color cycle; otherwise is black
if not args:
props.setdefault('color', ['black'])
if kwargs:
warnings._warn_proplot(f'Ignoring Cycle() keyword arg(s) {kwargs}.')
dicts = ()
# Merge cycler objects and/or update cycler objects with input kwargs
elif all(isinstance(arg, cycler.Cycler) for arg in args):
if kwargs:
warnings._warn_proplot(f'Ignoring Cycle() keyword arg(s) {kwargs}.')
if len(args) == 1 and not props:
return args[0]
dicts = tuple(arg.by_key() for arg in args)
# Get a cycler from a colormap
# NOTE: Passing discrete=True does not imply default_luminance=90 because
# someone might be trying to make qualitative colormap for use in 2D plot
else:
if isinstance(args[-1], Number):
args, samples = args[:-1], _not_none(samples_positional=args[-1], samples=samples) # noqa: #501
kwargs.setdefault('listmode', 'discrete')
kwargs.setdefault('filemode', 'discrete')
kwargs['discrete'] = True # triggers application of default 'samples'
kwargs['default_luminance'] = DEFAULT_CYCLE_LUMINANCE
cmap = Colormap(*args, name=name, samples=samples, **kwargs)
name = _not_none(name, cmap.name)
dict_ = {'color': [c if isinstance(c, str) else to_hex(c) for c in cmap.colors]}
dicts = (dict_,)
# Update the cyler property
dicts = dicts + (props,)
props = {}
for dict_ in dicts:
for key, value in dict_.items():
props.setdefault(key, []).extend(value)
# Build cycler with matching property lengths
maxlen = np.lcm.reduce([len(value) for value in props.values()])
props = {key: value * (maxlen // len(value)) for key, value in props.items()}
cycle = cycler.cycler(**props)
cycle.name = _not_none(name, '_no_name')
return cycle
[docs]def Norm(norm, *args, **kwargs):
"""
Return an arbitrary `~matplotlib.colors.Normalize` instance. See this
`tutorial <https://matplotlib.org/stable/tutorials/colors/colormapnorms.html>`__
for an introduction to matplotlib normalizers.
Parameters
----------
norm : str or `~matplotlib.colors.Normalize`
The normalizer specification. If a `~matplotlib.colors.Normalize`
instance already, the input argument is simply returned. Otherwise,
`norm` should be a string corresponding to one of the "registered"
colormap normalizers (see below table).
If `norm` is a list or tuple and the first element is a "registered"
normalizer name, subsequent elements are passed to the normalizer class
as positional arguments.
.. _norm_table:
=============================== =====================================
Key(s) Class
=============================== =====================================
``'null'``, ``'none'`` `~matplotlib.colors.NoNorm`
``'diverging'``, ``'div'`` `~proplot.colors.DivergingNorm`
``'segmented'``, ``'segments'`` `~proplot.colors.SegmentedNorm`
``'linear'`` `~matplotlib.colors.Normalize`
``'log'`` `~matplotlib.colors.LogNorm`
``'power'`` `~matplotlib.colors.PowerNorm`
``'symlog'`` `~matplotlib.colors.SymLogNorm`
=============================== =====================================
Other parameters
----------------
*args, **kwargs
Passed to the `~matplotlib.colors.Normalize` initializer.
Returns
-------
`~matplotlib.colors.Normalize`
A `~matplotlib.colors.Normalize` instance.
See also
--------
matplotlib.colors.Normalize
proplot.colors.DiscreteNorm
Colormap
"""
if np.iterable(norm) and not isinstance(norm, str):
norm, args = norm[0], (*norm[1:], *args)
if isinstance(norm, mcolors.Normalize):
return norm
if not isinstance(norm, str):
raise ValueError(f'Invalid norm name {norm!r}. Must be string.')
if norm not in NORMS:
raise ValueError(
f'Unknown normalizer {norm!r}. Options are: '
+ ', '.join(map(repr, NORMS))
+ '.'
)
if norm == 'symlog' and not args and 'linthresh' not in kwargs:
kwargs['linthresh'] = 1 # special case, needs argument
return NORMS[norm](*args, **kwargs)
[docs]def Locator(locator, *args, **kwargs):
"""
Return a `~matplotlib.ticker.Locator` instance.
Parameters
----------
locator : `~matplotlib.ticker.Locator`, str, float, or sequence
The locator specification, interpreted as follows:
* If a `~matplotlib.ticker.Locator` instance already, the input
argument is simply returned.
* If a sequence of numbers, these points are ticked. Returns a
`~matplotlib.ticker.FixedLocator`.
* If number, this specifies the *step size* between tick locations.
Returns a `~matplotlib.ticker.MultipleLocator`.
Otherwise, `locator` should be a string corresponding to one
of the "registered" locators (see below table). If `locator` is a
list or tuple and the first element is a "registered" locator name,
subsequent elements are passed to the locator class as positional
arguments. For example, ``pplt.Locator(('multiple', 5))`` is
equivalent to ``pplt.Locator('multiple', 5)``.
.. _locator_table:
======================= ============================================ =====================================================================================
Key Class Description
======================= ============================================ =====================================================================================
``'null'``, ``'none'`` `~matplotlib.ticker.NullLocator` No ticks
``'auto'`` `~matplotlib.ticker.AutoLocator` Major ticks at sensible locations
``'minor'`` `~matplotlib.ticker.AutoMinorLocator` Minor ticks at sensible locations
``'date'`` `~matplotlib.dates.AutoDateLocator` Default tick locations for datetime axes
``'fixed'`` `~matplotlib.ticker.FixedLocator` Ticks at these exact locations
``'index'`` `~matplotlib.ticker.IndexLocator` Ticks on the non-negative integers
``'linear'`` `~matplotlib.ticker.LinearLocator` Exactly ``N`` ticks encompassing axis limits, spaced as ``numpy.linspace(lo, hi, N)``
``'log'`` `~matplotlib.ticker.LogLocator` For log-scale axes
``'logminor'`` `~matplotlib.ticker.LogLocator` For log-scale axes on the 1st through 9th multiples of each power of the base
``'logit'`` `~matplotlib.ticker.LogitLocator` For logit-scale axes
``'logitminor'`` `~matplotlib.ticker.LogitLocator` For logit-scale axes with ``minor=True`` passed to `~matplotlib.ticker.LogitLocator`
``'maxn'`` `~matplotlib.ticker.MaxNLocator` No more than ``N`` ticks at sensible locations
``'multiple'`` `~matplotlib.ticker.MultipleLocator` Ticks every ``N`` step away from zero
``'symlog'`` `~matplotlib.ticker.SymmetricalLogLocator` For symlog-scale axes
``'symlogminor'`` `~matplotlib.ticker.SymmetricalLogLocator` For symlog-scale axes on the 1st through 9th multiples of each power of the base
``'theta'`` `~matplotlib.projections.polar.ThetaLocator` Like the base locator but default locations are every `numpy.pi`/8 radians
``'year'`` `~matplotlib.dates.YearLocator` Ticks every ``N`` years
``'month'`` `~matplotlib.dates.MonthLocator` Ticks every ``N`` months
``'weekday'`` `~matplotlib.dates.WeekdayLocator` Ticks every ``N`` weekdays
``'day'`` `~matplotlib.dates.DayLocator` Ticks every ``N`` days
``'hour'`` `~matplotlib.dates.HourLocator` Ticks every ``N`` hours
``'minute'`` `~matplotlib.dates.MinuteLocator` Ticks every ``N`` minutes
``'second'`` `~matplotlib.dates.SecondLocator` Ticks every ``N`` seconds
``'microsecond'`` `~matplotlib.dates.MicrosecondLocator` Ticks every ``N`` microseconds
``'lon'``, ``'deglon'`` `~proplot.ticker.LongitudeLocator` Longitude gridlines at sensible decimal locations
``'lat'``, ``'deglat'`` `~proplot.ticker.LatitudeLocator` Latitude gridlines at sensible decimal locations
``'dms'`` `~proplot.ticker.DegreeLocator` Gridlines on nice minute and second intervals
``'dmslon'`` `~proplot.ticker.LongitudeLocator` Longitude gridlines on nice minute and second intervals
``'dmslat'`` `~proplot.ticker.LatitudeLocator` Latitude gridlines on nice minute and second intervals
======================= ============================================ =====================================================================================
Other parameters
----------------
*args, **kwargs
Passed to the `~matplotlib.ticker.Locator` class.
Returns
-------
`~matplotlib.ticker.Locator`
A `~matplotlib.ticker.Locator` instance.
See also
--------
matplotlib.ticker.Locator
proplot.axes.CartesianAxes.format
proplot.axes.PolarAxes.format
proplot.axes.GeoAxes.format
proplot.axes.Axes.colorbar
Formatter
""" # noqa: E501
if np.iterable(locator) and not isinstance(locator, str) and not all(
isinstance(num, Number) for num in locator
):
locator, args = locator[0], (*locator[1:], *args)
if isinstance(locator, mticker.Locator):
return locator
if isinstance(locator, str):
if locator == 'index': # defaults
args = args or (1,)
if len(args) == 1:
args = (*args, 0)
elif locator in ('logminor', 'logitminor', 'symlogminor'): # presets
locator, _ = locator.split('minor')
if locator == 'logit':
kwargs.setdefault('minor', True)
else:
kwargs.setdefault('subs', np.arange(1, 10))
if locator in LOCATORS:
locator = LOCATORS[locator](*args, **kwargs)
else:
raise ValueError(
f'Unknown locator {locator!r}. Options are: '
+ ', '.join(map(repr, LOCATORS))
+ '.'
)
elif isinstance(locator, Number): # scalar variable
locator = mticker.MultipleLocator(locator, *args, **kwargs)
elif np.iterable(locator):
locator = mticker.FixedLocator(np.sort(locator), *args, **kwargs)
else:
raise ValueError(f'Invalid locator {locator!r}.')
return locator
[docs]def Scale(scale, *args, **kwargs):
"""
Return a `~matplotlib.scale.ScaleBase` instance.
Parameters
----------
scale : `~matplotlib.scale.ScaleBase`, str, or tuple
The axis scale specification. If a `~matplotlib.scale.ScaleBase`
instance already, the input argument is simply returned. Otherwise,
`scale` should be a string corresponding to one of the
"registered" axis scales or axis scale presets (see below table).
If `scale` is a list or tuple and the first element is a
"registered" scale name, subsequent elements are passed to the
scale class as positional arguments.
.. _scale_table:
================= ====================================== ===============================================
Key Class Description
================= ====================================== ===============================================
``'linear'`` `~proplot.scale.LinearScale` Linear
``'log'`` `~proplot.scale.LogScale` Logarithmic
``'symlog'`` `~proplot.scale.SymmetricalLogScale` Logarithmic beyond finite space around zero
``'logit'`` `~proplot.scale.LogitScale` Logistic
``'inverse'`` `~proplot.scale.InverseScale` Inverse
``'function'`` `~proplot.scale.FuncScale` Arbitrary forward and backwards transformations
``'sine'`` `~proplot.scale.SineLatitudeScale` Sine function (in degrees)
``'mercator'`` `~proplot.scale.MercatorLatitudeScale` Mercator latitude function (in degrees)
``'exp'`` `~proplot.scale.ExpScale` Arbitrary exponential function
``'power'`` `~proplot.scale.PowerScale` Arbitrary power function
``'cutoff'`` `~proplot.scale.CutoffScale` Arbitrary piecewise linear transformations
``'quadratic'`` `~proplot.scale.PowerScale` (preset) Quadratic function
``'cubic'`` `~proplot.scale.PowerScale` (preset) Cubic function
``'quartic'`` `~proplot.scale.PowerScale` (preset) Quartic function
``'db'`` `~proplot.scale.ExpScale` (preset) Ratio expressed as `decibels <db_>`_
``'np'`` `~proplot.scale.ExpScale` (preset) Ratio expressed as `nepers <np_>`_
``'idb'`` `~proplot.scale.ExpScale` (preset) `Decibels <db_>`_ expressed as ratio
``'inp'`` `~proplot.scale.ExpScale` (preset) `Nepers <np_>`_ expressed as ratio
``'pressure'`` `~proplot.scale.ExpScale` (preset) Height (in km) expressed linear in pressure
``'height'`` `~proplot.scale.ExpScale` (preset) Pressure (in hPa) expressed linear in height
================= ====================================== ===============================================
.. _db: https://en.wikipedia.org/wiki/Decibel
.. _np: https://en.wikipedia.org/wiki/Neper
Other parameters
----------------
*args, **kwargs
Passed to the `~matplotlib.scale.ScaleBase` class.
Returns
-------
`~matplotlib.scale.ScaleBase`
The scale instance.
See also
--------
matplotlib.scale.ScaleBase
proplot.axes.CartesianAxes.format
proplot.axes.CartesianAxes.dualx
proplot.axes.CartesianAxes.dualy
""" # noqa: E501
# NOTE: Why not try to interpret FuncScale arguments, like when lists
# of numbers are passed to Locator? Because FuncScale *itself* accepts
# ScaleBase classes as arguments... but constructor functions cannot
# do anything but return the class instance upon receiving one.
if np.iterable(scale) and not isinstance(scale, str):
scale, args = scale[0], (*scale[1:], *args)
if isinstance(scale, mscale.ScaleBase):
return scale
if not isinstance(scale, str):
raise ValueError(f'Invalid scale name {scale!r}. Must be string.')
scale = scale.lower()
if scale in SCALE_PRESETS:
if args or kwargs:
warnings._warn_proplot(
f'Scale {scale!r} is a scale *preset*. Ignoring positional '
'argument(s): {args} and keyword argument(s): {kwargs}. '
)
scale, *args = SCALE_PRESETS[scale]
if scale in SCALES:
scale = SCALES[scale]
else:
raise ValueError(
f'Unknown scale or preset {scale!r}. Options are: '
+ ', '.join(map(repr, (*SCALES, *SCALE_PRESETS)))
+ '.'
)
return scale(*args, **kwargs)
[docs]def Proj(name, basemap=None, **kwargs):
"""
Return a `cartopy.crs.Projection` or `~mpl_toolkits.basemap.Basemap` instance.
Parameters
----------
name : str, `cartopy.crs.Projection`, or `~mpl_toolkits.basemap.Basemap`
The projection name or projection class instance. If the latter, it
is simply returned. If the former, it must correspond to one of the
`PROJ <https://proj.org>`__ projection name shorthands, like in
basemap.
The following table lists the valid projection name shorthands, their
full names (with links to the relevant
`PROJ documentation <https://proj4.org/operations/projections>`__),
and whether they are available in the cartopy and basemap packages.
(added) indicates a projection class that proplot has "added"
to cartopy using the cartopy API.
.. _proj_table:
============= =============================================== ========= =======
Key Name Cartopy Basemap
============= =============================================== ========= =======
``'aea'`` `Albers Equal Area <aea_>`_ ✓ ✓
``'aeqd'`` `Azimuthal Equidistant <aeqd_>`_ ✓ ✓
``'aitoff'`` `Aitoff <aitoff_>`_ ✓ (added) ✗
``'cass'`` `Cassini-Soldner <cass_>`_ ✗ ✓
``'cea'`` `Cylindrical Equal Area <cea_>`_ ✗ ✓
``'cyl'`` `Cylindrical Equidistant <eqc_>`_ ✓ ✓
``'eck1'`` `Eckert I <eck1_>`_ ✓ ✗
``'eck2'`` `Eckert II <eck2_>`_ ✓ ✗
``'eck3'`` `Eckert III <eck3_>`_ ✓ ✗
``'eck4'`` `Eckert IV <eck4_>`_ ✓ ✓
``'eck5'`` `Eckert V <eck5_>`_ ✓ ✗
``'eck6'`` `Eckert VI <eck6_>`_ ✓ ✗
``'eqdc'`` `Equidistant Conic <eqdc_>`_ ✓ ✓
``'eqc'`` `Cylindrical Equidistant <eqc_>`_ ✓ ✓
``'eqearth'`` `Equal Earth <eqearth_>`_ ✓ ✗
``'europp'`` Euro PP (Europe) ✓ ✗
``'gall'`` `Gall Stereographic Cylindrical <gall_>`_ ✗ ✓
``'geos'`` `Geostationary <geos_>`_ ✓ ✓
``'gnom'`` `Gnomonic <gnom_>`_ ✓ ✓
``'hammer'`` `Hammer <hammer_>`_ ✓ (added) ✓
``'igh'`` `Interrupted Goode Homolosine <igh_>`_ ✓ ✗
``'kav7'`` `Kavrayskiy VII <kav7_>`_ ✓ (added) ✓
``'laea'`` `Lambert Azimuthal Equal Area <laea_>`_ ✓ ✓
``'lcc'`` `Lambert Conformal <lcc_>`_ ✓ ✓
``'lcyl'`` Lambert Cylindrical ✓ ✗
``'mbtfpq'`` `McBryde-Thomas Flat-Polar Quartic <mbtfpq_>`_ ✗ ✓
``'merc'`` `Mercator <merc_>`_ ✓ ✓
``'mill'`` `Miller Cylindrical <mill_>`_ ✓ ✓
``'moll'`` `Mollweide <moll_>`_ ✓ ✓
``'npaeqd'`` North-Polar Azimuthal Equidistant ✓ (added) ✓
``'npgnom'`` North-Polar Gnomonic ✓ (added) ✗
``'nplaea'`` North-Polar Lambert Azimuthal ✓ (added) ✓
``'npstere'`` North-Polar Stereographic ✓ ✓
``'nsper'`` `Near-Sided Perspective <nsper_>`_ ✓ ✓
``'osni'`` OSNI (Ireland) ✓ ✗
``'osgb'`` OSGB (UK) ✓ ✗
``'omerc'`` `Oblique Mercator <omerc_>`_ ✗ ✓
``'ortho'`` `Orthographic <ortho_>`_ ✓ ✓
``'pcarree'`` `Cylindrical Equidistant <eqc_>`_ ✓ ✓
``'poly'`` `Polyconic <poly_>`_ ✗ ✓
``'rotpole'`` Rotated Pole ✓ ✓
``'sinu'`` `Sinusoidal <sinu_>`_ ✓ ✓
``'spaeqd'`` South-Polar Azimuthal Equidistant ✓ (added) ✓
``'spgnom'`` South-Polar Gnomonic ✓ (added) ✗
``'splaea'`` South-Polar Lambert Azimuthal ✓ (added) ✓
``'spstere'`` South-Polar Stereographic ✓ ✓
``'stere'`` `Stereographic <stere_>`_ ✓ ✓
``'tmerc'`` `Transverse Mercator <tmerc_>`_ ✓ ✓
``'utm'`` `Universal Transverse Mercator <utm_>`_ ✓ ✗
``'vandg'`` `van der Grinten <vandg_>`_ ✗ ✓
``'wintri'`` `Winkel tripel <wintri_>`_ ✓ (added) ✗
============= =============================================== ========= =======
basemap : bool, optional
Whether to use the basemap package as opposed to the cartopy package.
Default is :rc:`basemap`.
lonlim : 2-tuple of float, optional
Alternative way to specify `llcrnrlon` and `urcrnrlon` for basemap
projections.
latlim : 2-tuple of float, optional
Alternative way to specify `llcrnrlat` and `urcrnrlat` for basemap
projections.
Other parameters
----------------
**kwargs
Passed to the `mpl_toolkits.basemap.Basemap` or `cartopy.crs.Projection`
class. For cartopy axes, proplot translates `lon_0` and `lat_0` to
`central_longitude` and `central_latitude`.
Returns
-------
proj : `~mpl_toolkits.basemap.Basemap` or `~cartopy.crs.Projection`
The projection instance.
See also
--------
mpl_toolkits.basemap.Basemap
cartopy.crs.Projection
proplot.ui.subplots
proplot.axes.GeoAxes
References
----------
For more information on map projections, see the
`wikipedia page <https://en.wikipedia.org/wiki/Map_projection>`__ and the
`PROJ <https://proj.org>`__ documentation.
.. _aea: https://proj4.org/operations/projections/aea.html
.. _aeqd: https://proj4.org/operations/projections/aeqd.html
.. _aitoff: https://proj4.org/operations/projections/aitoff.html
.. _cass: https://proj4.org/operations/projections/cass.html
.. _cea: https://proj4.org/operations/projections/cea.html
.. _eqc: https://proj4.org/operations/projections/eqc.html
.. _eck1: https://proj4.org/operations/projections/eck1.html
.. _eck2: https://proj4.org/operations/projections/eck2.html
.. _eck3: https://proj4.org/operations/projections/eck3.html
.. _eck4: https://proj4.org/operations/projections/eck4.html
.. _eck5: https://proj4.org/operations/projections/eck5.html
.. _eck6: https://proj4.org/operations/projections/eck6.html
.. _eqdc: https://proj4.org/operations/projections/eqdc.html
.. _eqc: https://proj4.org/operations/projections/eqc.html
.. _eqearth: https://proj4.org/operations/projections/eqearth.html
.. _gall: https://proj4.org/operations/projections/gall.html
.. _geos: https://proj4.org/operations/projections/geos.html
.. _gnom: https://proj4.org/operations/projections/gnom.html
.. _hammer: https://proj4.org/operations/projections/hammer.html
.. _igh: https://proj4.org/operations/projections/igh.html
.. _kav7: https://proj4.org/operations/projections/kav7.html
.. _laea: https://proj4.org/operations/projections/laea.html
.. _lcc: https://proj4.org/operations/projections/lcc.html
.. _mbtfpq: https://proj4.org/operations/projections/mbtfpq.html
.. _merc: https://proj4.org/operations/projections/merc.html
.. _mill: https://proj4.org/operations/projections/mill.html
.. _moll: https://proj4.org/operations/projections/moll.html
.. _nsper: https://proj4.org/operations/projections/nsper.html
.. _omerc: https://proj4.org/operations/projections/omerc.html
.. _ortho: https://proj4.org/operations/projections/ortho.html
.. _eqc: https://proj4.org/operations/projections/eqc.html
.. _poly: https://proj4.org/operations/projections/poly.html
.. _sinu: https://proj4.org/operations/projections/sinu.html
.. _stere: https://proj4.org/operations/projections/stere.html
.. _tmerc: https://proj4.org/operations/projections/tmerc.html
.. _utm: https://proj4.org/operations/projections/utm.html
.. _vandg: https://proj4.org/operations/projections/vandg.html
.. _wintri: https://proj4.org/operations/projections/wintri.html
""" # noqa: E501
# Class instances
basemap = _not_none(basemap, rc['basemap'])
is_crs = Projection is not object and isinstance(name, Projection)
is_basemap = Basemap is not object and isinstance(name, Basemap)
include_axes = kwargs.pop('include_axes', False) # for error message
if is_crs or is_basemap:
proj = name
package = 'cartopy' if is_crs else 'basemap'
if kwargs:
warnings._warn_proplot(f'Ignoring Proj() keyword arg(s): {kwargs!r}.')
# Unknown
elif not isinstance(name, str):
raise ValueError(
f'Unexpected projection {name!r}. Must be PROJ string name, '
'cartopy.crs.Projection, or mpl_toolkits.basemap.Basemap.'
)
# Basemap
# NOTE: Known issue that basemap sometimes produces backwards maps:
# https://stackoverflow.com/q/56299971/4970632
# NOTE: We set rsphere to fix non-conda installed basemap issue:
# https://github.com/matplotlib/basemap/issues/361
# NOTE: Adjust lon_0 tof fix issues with Robinson (and related?) projections
# https://stackoverflow.com/questions/56299971/ (also triggers 'no room for axes')
# NOTE: Unlike cartopy, basemap resolution is configured
# on initialization and controls *all* features.
elif basemap:
import mpl_toolkits.basemap as mbasemap
package = 'basemap'
if dependencies._version_mpl >= 3.3:
raise RuntimeError(
'Basemap is no longer maintained and is incompatible with '
'matplotlib >= 3.3. Please use cartopy as your geographic '
'plotting backend or downgrade to matplotlib <= 3.2.'
)
if 'lonlim' in kwargs:
kwargs['llcrnrlon'], kwargs['urcrnrlon'] = kwargs.pop('lonlim')
if 'latlim' in kwargs:
kwargs['llcrnrlat'], kwargs['urcrnrlat'] = kwargs.pop('latlim')
name = PROJ_ALIASES.get(name, name)
proj_kw = PROJ_DEFAULTS.get(name, {}).copy()
proj_kw.update(kwargs)
proj_kw.setdefault('fix_aspect', True)
if proj_kw.get('lon_0', 0) > 0:
proj_kw['lon_0'] -= 360
if name[:2] in ('np', 'sp'):
proj_kw.setdefault('round', True)
if name == 'geos':
proj_kw.setdefault('rsphere', (6378137.00, 6356752.3142))
reso = _not_none(
reso=proj_kw.pop('reso', None),
resolution=proj_kw.pop('resolution', None),
default=rc['reso']
)
if reso in RESOS_BASEMAP:
reso = RESOS_BASEMAP[reso]
else:
raise ValueError(
f'Invalid resolution {reso!r}. Options are: '
+ ', '.join(map(repr, RESOS_BASEMAP))
+ '.'
)
proj_kw.update({'resolution': reso, 'projection': name})
try:
proj = mbasemap.Basemap(**proj_kw) # will raise helpful warning
except ValueError as err:
message = str(err)
message = message.strip()
message = message.replace('projection', 'basemap projection')
message = message.replace('supported', 'known')
if include_axes:
from . import axes as paxes # avoid circular imports
message = message.replace('projection.', 'projection or axes subclass.')
message += '\nThe known axes subclasses are:\n' + paxes._cls_table
raise ValueError(message) from None
# Cartopy
# NOTE: Error message matches basemap invalid projection message
else:
import cartopy.crs as ccrs # noqa: F401
package = 'cartopy'
proj_kw = {PROJ_ALIASES_KW.get(key, key): value for key, value in kwargs.items()} # noqa: E501
if 'boundinglat' in proj_kw:
raise ValueError('"boundinglat" must be passed to the ax.format() command for cartopy axes.') # noqa: E501
try:
crs = PROJS[name]
except KeyError:
message = f'{name!r} is an unknown cartopy projection class.\n'
message += 'The known cartopy projection classes are:\n'
message += '\n'.join(
' ' + key + ' ' * (max(map(len, PROJS)) - len(key) + 10) + cls.__name__
for key, cls in PROJS.items()
)
if include_axes:
from . import axes as paxes # avoid circular imports
message = message.replace('class.', 'class or axes subclass.')
message += '\nThe known axes subclasses are:\n' + paxes._cls_table
raise ValueError(message) from None
if name == 'geos': # fix common mistake
proj_kw.pop('central_latitude', None)
proj = crs(**proj_kw)
proj._proj_package = package
return proj
# Deprecated
Colors = warnings._rename_objs(
'0.8', Colors=get_colors
)