Naturalcolors tutorial¶

In [1]:

import numpy as np
import importlib
import matplotlib as mpl
import naturalcolors.colorpalette as ncp

import numpy as np import importlib import matplotlib as mpl import naturalcolors.colorpalette as ncp

Documentation¶

Documentation on how to create a colormap from a list of colors (a listed colormap) or by specifying anchor points between which the RGB(A) colors are interpolated (a linear segmented colormap) can be found here:

https://matplotlib.org/3.1.0/tutorials/colors/colormap-manipulation.html

The naturalcolors colormap¶

Naturalcolors provides wrapper functions to create a colormap from a list of colors in a json file. The colormap is generated by calling the naturalcolors() function from the colorpalette submodule.

In [3]:

natcmap_list,natcmap_linseg = ncp.naturalcolors()

natcmap_list,natcmap_linseg = ncp.naturalcolors()

The resulting listed and linear segmented colormaps can be visualized either by a colorbar or a color circle

In [13]:

ncp.drawColorBar(natcmap_linseg)

ncp.drawColorBar(natcmap_linseg)

Draw a color circle with the naturalcolors colormap

In [14]:

ncp.drawColorCircle(natcmap_linseg, 15, 2000)

ncp.drawColorCircle(natcmap_linseg, 15, 2000)

Custom colormaps¶

You can create your own custom colormaps directly from a list of colors or by loading them from a json file using the load_colors function from the colorpalette submodule.

The json file should be structures as a list of rgb(a) colors:

[[234,33,59],
[237,65,55],
[239,102,58],
...]

In [20]:

colors = [[0.31, 0.45, 0.56],[0.9,0.9,0.9], [0.75, 0.51, 0.38]]
cmap_list,cmap_linseg = ncp.make_colormap(colors, 'BlueWhiteOrange')
ncp.drawColorCircle(cmap_linseg, area=500)

colors = [[0.31, 0.45, 0.56],[0.9,0.9,0.9], [0.75, 0.51, 0.38]] cmap_list,cmap_linseg = ncp.make_colormap(colors, 'BlueWhiteOrange') ncp.drawColorCircle(cmap_linseg, area=500)

Registered colormaps¶

Registered colormaps can also be called directly from their name

In [21]:

ncp.drawColorCircle('Blues', area=500)

ncp.drawColorCircle('Blues', area=500)

A registered colormap can be accessed from its name by the following equivalent commands:

In [28]:

# from the cmap submodule
mpl.cm.get_cmap('Blues')

# from the pyplot submodule
mpl.pyplot.get_cmap('Blues')

# from the cmap submodule mpl.cm.get_cmap('Blues') # from the pyplot submodule mpl.pyplot.get_cmap('Blues')

Out[28]:

<matplotlib.colors.LinearSegmentedColormap at 0x7f53bc975278>

A list of n colors can be extracted from a colormap using the get_colors function of the colorpalette submodule (calls cmap(np.linspace(0,1,n) internally). Using the flag scramble=True (default=False) rearranges the color array as [[first rgb],[last rgb],[second rgb],...]]

In [44]:

ncp.get_colors('Blues', 5, scramble=True)

ncp.get_colors('Blues', 5, scramble=True)

Out[44]:

array([[0.96862745, 0.98431373, 1.        , 1.        ],
       [0.03137255, 0.18823529, 0.41960784, 1.        ],
       [0.77524029, 0.85830065, 0.9368243 , 1.        ],
       [0.12710496, 0.44018454, 0.70749712, 1.        ],
       [0.41708574, 0.68063053, 0.83823145, 1.        ]])