def bezier(icolors,
ncol=255,
correctlightness=True,
reverse=False,
cmap=None,
lch=False):
"""
interpolates between a set of colors using a bezier spline
"""
# Bezier interpolation functions
int2 = lambda c0, c1, t: (1. - t) * c0 + t * c1
int3 = lambda c0, c1, c2, t: (1. - t) * (1. - t) * c0 + 2. * (
1. - t) * t * c1 + t * t * c2
int4 = lambda c0, c1, c2, c3, t: (1. - t) * (1. - t) * (
1. - t) * c0 + 3. * (1. - t) * (1. - t) * t * c1 + 3. * (
1. - t) * t * t * c2 + t * t * t * c3
# Check
assert ncol > 1, 'Number of interpolated colours must be > 1'
# Convert colours to L*a*b
if lch:
colors = [rgb2lch(*col2rgb(i)) for i in icolors] # in lab
else:
colors = [rgb2lab(*col2rgb(i)) for i in icolors] # in lab
# Check - 2
icol = len(colors)
if (icol > 5):
raise ValueError('number of input colors > 5 not supported.')
# Check sequential or diverging colours, i.e. check for increasing/decreasing lightness
if (icol > 1):
lights = np.array([i[0] for i in colors])
dlight = np.diff(lights)
if np.all(dlight < 0.) or np.all(dlight >= 0.):
idiverge = False
# if icol > 4:
# raise ValueError('only diverging colours supported in case of 5 input colours.')
else:
idiverge = True
if icol == 4:
print('ll', lights)
raise ValueError(
'colours must have increasing or decreasing lightness in case of even number of colors: '
+ ',' + ','.join([str(i) for i in lights]))
# Interpolate colours
if icol == 1:
lab = [colors[0] for i in range(ncol)]
elif icol == 2:
lab0 = colors[0]
lab1 = colors[1]
# linear interpolation
lab = list()
for it in range(ncol):
t = float(it) / float(ncol - 1)
if correctlightness:
t = correct_lightness(int2, lab0[0], lab1[0], t)
lab.append(tuple([int2(lab0[i], lab1[i], t) for i in range(3)]))
elif icol == 3:
if idiverge:
assert (
ncol % 2
) == 1, 'number of colors has to be odd for bezier interpolation with 3 diverging colors.'
ncol2 = ncol // 2 + 1
# two separate interpolations
col1 = bezier(icolors[:2], ncol2)
col2 = bezier(icolors[1:], ncol2)
col1.extend(col2[1:])
if lch:
lab = [rgb2lch(*rgb012rgb(*i)) for i in col1]
else:
lab = [rgb2lab(*rgb012rgb(*i)) for i in col1]
else:
lab0 = colors[0]
lab1 = colors[1]
lab2 = colors[2]
# quadratic bezier interpolation
lab = list()
for it in range(ncol):
t = float(it) / float(ncol - 1)
if correctlightness:
t = correct_lightness(int3, lab0[0], lab1[0], lab2[0], t)
lab.append(
tuple([
int3(lab0[i], lab1[i], lab2[i], t) for i in range(3)
]))
elif icol == 4:
lab0 = colors[0]
lab1 = colors[1]
lab2 = colors[2]
lab3 = colors[3]
# cubic bezier interpolation
lab = list()
for it in range(ncol):
t = float(it) / float(ncol - 1)
if correctlightness:
t = correct_lightness(int4, lab0[0], lab1[0], lab2[0], lab3[0],
t)
lab.append(
tuple([
int4(lab0[i], lab1[i], lab2[i], lab3[i], t)
for i in range(3)
]))
elif icol == 5:
assert (
ncol % 2
) == 1, 'number of colors has to be odd for bezier interpolation with 5 colors.'
ncol2 = ncol // 2 + 1
col1 = bezier(icolors[:3], ncol2)
col2 = bezier(icolors[2:], ncol2)
col1.extend(col2[1:])
if lch:
lab = [rgb2lch(*rgb012rgb(*i)) for i in col1]
else:
lab = [rgb2lab(*rgb012rgb(*i)) for i in col1]
else:
raise ValueError('number of input colors > 5 not supported.')
# Reverse colours
if reverse:
lab = lab[::-1]
# rgb [0-1]
if lch:
cout = [rgb2rgb01(*lch2rgb(*i)) for i in lab]
else:
cout = [rgb2rgb01(*lab2rgb(*i)) for i in lab]
# Register colour map with matplotlib
if cmap is not None:
from matplotlib.colors import ListedColormap
from matplotlib.cm import register_cmap
iscmap = ListedColormap(cout, name=cmap, N=ncol)
register_cmap(name=cmap, cmap=iscmap)
return cout
def sron_colors(cmap='palette1', ncol=9, cname=None, rgb=False, rgb256=False, reverse=False):
"""
Distinct colour palettes of Paul Tol at SRON - Netherlands Institute for Space Research
Definition
----------
def sron_colors(cmap='palette1', ncol=9, cname=None, rgb=False, rgb256=False, reverse=False):
Input
-----
None
Optional Input
--------------
cmap Colour palette name
palette1: 1-12 colours; orignal palette is ncol=9
palette2: more regular hue and saturation (21 colours)
palette2-light: 7 light colours of palette2
palette2-medium: 7 medium colours of palette2
palette2-dark: 7 darker colours of palette2
gray / grey: 4 colours optimized for printing in grey scale
ylorbr 3-9 colours from sron_maps('ylorbr')
buylrd 3-11 colours from sron_maps('buylrd')
rainbow 4-12 colours from sron_maps('rainbow')
banded-rainbow 14, 15, 18, 21 banded rainbow schemes
ncol number of desired colors if palette1 (1-12)
cname if given, name of registered colormap
rgb if True, return RGB value tuple between 0 and 1
rgb256 if True, return RGB value tuple between 0 and 255
reverse if True, reverse colormap
Output
------
matplotlip listed colormap of ncol colours
Restrictions
------------
None
Examples
--------
>>> print(sron_colors('palette1', 3, rgb256=True))
[(68, 119, 170), (221, 204, 119), (204, 102, 119)]
>>> print(sron_colors('palette2-light', rgb256=True)[0])
(119, 170, 221)
>>> print(sron_colors('ylorbr', 4, rgb256=True, reverse=True)[0])
(204, 76, 2)
License
-------
This file is part of the JAMS Python package, distributed under the MIT
License. The JAMS Python package originates from the former UFZ Python library,
Department of Computational Hydrosystems, Helmholtz Centre for Environmental
Research - UFZ, Leipzig, Germany.
Copyright (c) 2016 Matthias Cuntz - mc (at) macu (dot) de
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
History
-------
Written, MC, May 2016
"""
from jams.color import hex2rgb01
if cmap.lower() == 'palette1':
assert (ncol>0) and (ncol<13), 'palette1 has 1-12 colours.'
cols = []
for i in palette1[ncol-1]:
cols.append(tuple(hex2rgb01(i)))
elif cmap.lower() == 'palette2':
cols = []
for i in range(7):
cols.append(tuple(hex2rgb01(palette2_light[i])))
cols.append(tuple(hex2rgb01(palette2_medium[i])))
cols.append(tuple(hex2rgb01(palette2_dark[i])))
elif cmap.lower() == 'palette2-light':
cols = []
for i in palette2_light:
cols.append(tuple(hex2rgb01(i)))
elif cmap.lower() == 'palette2-medium':
cols = []
for i in palette2_medium:
cols.append(tuple(hex2rgb01(i)))
elif cmap.lower() == 'palette2-dark':
cols = []
for i in palette2_dark:
cols.append(tuple(hex2rgb01(i)))
elif cmap.lower() == 'grey' or cmap.lower() == 'gray':
cols = []
for i in greysafe:
cols.append(tuple(hex2rgb01(i)))
elif cmap.lower() == 'ylorbr':
assert (ncol>2) and (ncol<10), 'ylorbr has 3-9 colours.'
cols = []
for i in palette_ylorbr[ncol-3]:
cols.append(tuple(hex2rgb01(i)))
elif cmap.lower() == 'buylrd':
assert (ncol>2) and (ncol<12), 'buylrd has 3-11 colours.'
cols = []
for i in palette_buylrd[ncol-3]:
cols.append(tuple(hex2rgb01(i)))
elif cmap.lower() == 'rainbow':
assert (ncol>3) and (ncol<13), 'rainbow has 4-12 colours.'
cols = []
for i in palette_rainbow[ncol-4]:
cols.append(tuple(hex2rgb01(i)))
elif cmap.lower() == 'banded-rainbow':
if ncol==14:
psel = palette_rainbow_band[0]
elif ncol==15:
psel = palette_rainbow_band[1]
elif ncol==18:
psel = palette_rainbow_band[2]
elif ncol==21:
psel = palette_rainbow_band[3]
else:
raise ValueError('banded-rainbow palette has 14, 15, 18, or 21 colours.')
cols = []
for i in psel:
cols.append(tuple(hex2rgb01(i)))
else:
raise ValueError('Colour palette not known: '+cmap)
if reverse: cols = cols[::-1]
if (not rgb) and (not rgb256):
from matplotlib.colors import ListedColormap
ccmap = ListedColormap(cols)
if cname:
from matplotlib.cm import register_cmap, get_cmap
register_cmap(cname, ccmap)
return get_cmap(cname)
else:
return ccmap
else:
if rgb256:
from jams.color import rgb012rgb
return [ rgb012rgb(*i) for i in cols ]
else:
return cols
def sron_maps(cmap, ncol=256, offset=0, upper=1,
cname=None, rgb=False, rgb256=False, reverse=False, grey=False, gray=False):
"""
Colour maps of Paul Tol at SRON - Netherlands Institute for Space Research
Definition
----------
def sron_maps(cmap, ncol=256, offset=0, upper=1,
cname=None, rgb=False, rgb256=False, reverse=False, grey=False, gray=False):
Input
-----
cmap Colour map name
buylrd: blue-yellow-red diverging
rainbow: rainbow
ylorbr: yellow-orange-red sequential
Optional Input
--------------
ncol number of desired colors
offset bottom fraction to exclude (0-1)
upper upper most fraction included (0-1)
cname if given, name of registered colormap
rgb if True, return RGB value tuple between 0 and 1
rgb256 if True, return RGB value tuple between 0 and 255
reverse if True, reverse colormap
grey if True, return grey equivalent
gray same as grey
Output
------
matplotlip listed colormap of ncol colours
Restrictions
------------
None
Examples
--------
cmap = sron_maps('rainbow', 256)
cc = sron_maps('buylrd', 11, rgb=True)
License
-------
This file is part of the JAMS Python package, distributed under the MIT
License. The JAMS Python package originates from the former UFZ Python library,
Department of Computational Hydrosystems, Helmholtz Centre for Environmental
Research - UFZ, Leipzig, Germany.
Copyright (c) 2016 Matthias Cuntz - mc (at) macu (dot) de
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
History
-------
Written, MC, May 2016
"""
if cmap == 'ylorbr':
from scipy.special import erf
cols = []
for i in range(ncol):
x = offset + float(i)/float(ncol-1) * (upper-offset)
if cmap == 'buylrd':
cols.append(tuple(buylrd(x)))
elif cmap == 'rainbow':
cols.append(tuple(rainbow(x)))
elif cmap == 'ylorbr':
cols.append(tuple(ylorbr(x)))
else:
raise ValueError('Colour map not known: '+cmap)
if reverse: cols = cols[::-1]
if grey or gray:
for i, cc in enumerate(cols):
isgray = 0.2125*cc[0] + 0.7154*cc[1] + 0.072*cc[2]
cols[i] = (isgray,isgray,isgray)
if (not rgb) and (not rgb256):
from matplotlib.colors import ListedColormap
ccmap = ListedColormap(cols)
if cname:
from matplotlib.cm import register_cmap, get_cmap
register_cmap(cname, ccmap)
return get_cmap(cname)
else:
return ccmap
else:
if rgb256:
from jams.color import rgb012rgb
return [ rgb012rgb(*i) for i in cols ]
else:
return cols
def get_brewer(cname=None,
names=False,
rgb=False,
rgb256=False,
reverse=False,
grey=False,
gray=False):
"""
Get colour map either as registered handle or as RGB values (0-255 or 0-1).
Examples
--------
>>> import numpy as np
>>> from jams.autostring import astr
>>> cc = get_brewer('blues4',rgb=True)
>>> print(astr(np.array(cc[0]), 4))
['0.9373' '0.9529' '1.0000']
>>> cc = get_brewer('Blues4',rgb256=True)
>>> print(cc[0])
(239, 243, 255)
>>> cc = get_brewer('bLuEs4',rgb256=True,reverse=True)
>>> print(cc[-1])
(239, 243, 255)
>>> print(cc[0])
(33, 113, 181)
>>> cc = get_brewer('blues4',rgb256=True,grey=True)
>>> print(astr(np.array(cc[0]), 4))
['242.9897' '242.9897' '242.9897']
"""
from jams.color import rgb2rgb01, rgb012rgb
if names:
if names.lower() == 'sequential':
return list(brewer_sequential.keys())
elif names.lower() == 'diverging':
return list(brewer_diverging.keys())
elif names.lower() == 'qualitative':
return list(brewer_qualitative.keys())
elif names.lower() == 'osu':
return list(oregon.keys())
elif names.lower() == 'ncl_large':
return list(ncl_large.keys())
elif names.lower() == 'ncl_small':
return list(ncl_small.keys())
elif names.lower() == 'ncl_meteo_swiss':
return list(ncl_meteo_swiss.keys())
elif names.lower() == 'mma' or names.lower() == 'mathematica':
return list(mathematica.keys())
else:
cmaps = list(all_maps.keys())
return cmaps
else:
cname = capitalise(cname)
cpool = all_maps[cname][:]
if (not rgb) and (not rgb256):
# register colour map with matplotlib
from matplotlib.cm import get_cmap
register_brewer(cname, reverse=reverse, grey=grey, gray=gray)
return get_cmap(cname)
elif rgb:
# tuple 0-1
if cname in all255_maps:
cpool = [rgb2rgb01(*i) for i in cpool]
elif rgb256:
# tuple 0-255
if cname not in all255_maps:
cpool = [rgb012rgb(*i) for i in cpool]
if reverse:
cpool = cpool[::-1]
if grey or gray:
for j in range(len(cpool)):
isgray = 0.2125 * cpool[j][0] + 0.7154 * cpool[j][
1] + 0.072 * cpool[j][2]
cpool[j] = (isgray, isgray, isgray)
return cpool