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Function to lighten any color in matplotlib
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def lighten_color(color, amount=0.5): | |
""" | |
Lightens the given color by multiplying (1-luminosity) by the given amount. | |
Input can be matplotlib color string, hex string, or RGB tuple. | |
Examples: | |
>> lighten_color('g', 0.3) | |
>> lighten_color('#F034A3', 0.6) | |
>> lighten_color((.3,.55,.1), 0.5) | |
""" | |
import matplotlib.colors as mc | |
import colorsys | |
try: | |
c = mc.cnames[color] | |
except: | |
c = color | |
c = np.array(colorsys.rgb_to_hls(*mc.to_rgb(c))) | |
return colorsys.hls_to_rgb(c[0],1-amount * (1-c[1]),c[2]) |
Also note that F Lekschas proposed a very good adaption on StackOverflow (edit 3):
c = np.array(colorsys.rgb_to_hls(*mc.to_rgb(c)))
hls = (c[0], max(0, min(1, amount * c[1])), c[2])
rgb = colorsys.hls_to_rgb(*hls)
return mc.to_hex(rgb)
such that the color gets brighter when amount > 1 and darker when amount < 1. I also restricted the luminosity to [0,1] as values outside don't make sense. ~ F Lekschas
Made a version of it that takes RGB values from 0-255
def adjust_lightness(input_color, amount):
color = (input_color[0]/255, input_color[1]/255, input_color[2]/255)
try:
c = mc.cnames[color]
except:
c = color
c = colorsys.rgb_to_hls(*mc.to_rgb(c))
float_color = colorsys.hls_to_rgb(c[0], max(0, min(1, amount * c[1])), c[2])
return list(round(i*255) for i in float_color)
Found this Gist thanks to this StackOverflow link
In case you need to new custom LinearSegmentedColormap like I did. The original Stackoverflow Question
def custom_cmap_lightness(color, under=0.8, over=1.3):
color_ligten = []
for amount in np.linspace(under,over,1000):
try:
c = mc.cnames[color]
except:
c = color
c = colorsys.rgb_to_hls(*mc.to_rgb(c))
new_color = colorsys.hls_to_rgb(c[0], max(0, min(1, amount * c[1])), c[2])
color_ligten.append(new_color)
color_ligten.reverse()
new_cmp = LinearSegmentedColormap.from_list('testCmap', colors=color_ligten, N=256)
return new_cmp
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This is great, thank you 👍 Love that you also included docstrings with examples.
Note that if you want to get back a hex value, you can do:
I've also adjusted spacing and added an optional paranthesis to make visually clear that we don't multiply
1-amount
by1-c[1]
but rather do1
minusamount*(1-c[1])
.