Colormaps¶

This section shows the different colormaps that are available in datachart module. The colormaps are used to customize the colors of the charts.

datachart uses pypalettes under the hood, giving you access to 2500+ color palettes. A curated selection of popular palettes is available via the datachart.constants.COLORS constant, but you can use any valid pypalettes palette name directly.

The predefined palettes include:

• Sequential: Blues, Greens, Oranges, Purples, Reds, Sunset2, YlGnBu, YlOrRd, PuBuGn
• Diverging: RdBu, BrBG, PuOr, Spectral, RdYlBu, RdYlGn
• Categorical: Pastel, Set2, Accent, Dark2, Paired, Set1
• Grayscale: Greys (print-friendly)
• Color-blind friendly: Viridis, Cividis, Inferno, Plasma

In [1]:

from typing import List, Tuple

import numpy as np
import matplotlib.pyplot as plt

from typing import List, Tuple import numpy as np import matplotlib.pyplot as plt

In [2]:

from datachart.constants import COLORS
from datachart.utils._internal.colors import get_colormap

from datachart.constants import COLORS from datachart.utils._internal.colors import get_colormap

In [3]:

def plot_color_gradients(cmap_list: List[Tuple[str, str]], n_sections: int = 256):
    """Plots the gradients of multiple colormaps.

    Args:
        cmap_list (List[Tuple[str, str]]): The list of colormaps to plot.
        n_sections (int, optional): The number of sections to plot. Defaults to 256.

    """

    gradient = np.linspace(0, 1, n_sections)
    gradient = np.vstack((gradient, gradient))

    # Create figure and adjust figure height to number of colormaps
    nrows = len(cmap_list)
    figh = 0.35 + 0.15 + (nrows + (nrows - 1) * 0.1) * 0.22
    fig, axs = plt.subplots(nrows=nrows + 1, figsize=(8.2, figh))
    fig.subplots_adjust(top=1 - 0.35 / figh, bottom=0.15 / figh, left=0.2, right=0.99)
    axs[0].set_title(f"datachart colormaps", fontsize=14)

    for ax, (name, value) in zip(axs, cmap_list):
        ax.imshow(gradient, aspect="auto", cmap=get_colormap(value))
        ax.text(
            -0.01,
            0.5,
            name,
            va="center",
            ha="right",
            fontsize=10,
            transform=ax.transAxes,
        )

    # Turn off *all* ticks & spines, not just the ones with colormaps.
    for ax in axs:
        ax.set_axis_off()

def plot_color_gradients(cmap_list: List[Tuple[str, str]], n_sections: int = 256): """Plots the gradients of multiple colormaps. Args: cmap_list (List[Tuple[str, str]]): The list of colormaps to plot. n_sections (int, optional): The number of sections to plot. Defaults to 256. """ gradient = np.linspace(0, 1, n_sections) gradient = np.vstack((gradient, gradient)) # Create figure and adjust figure height to number of colormaps nrows = len(cmap_list) figh = 0.35 + 0.15 + (nrows + (nrows - 1) * 0.1) * 0.22 fig, axs = plt.subplots(nrows=nrows + 1, figsize=(8.2, figh)) fig.subplots_adjust(top=1 - 0.35 / figh, bottom=0.15 / figh, left=0.2, right=0.99) axs[0].set_title(f"datachart colormaps", fontsize=14) for ax, (name, value) in zip(axs, cmap_list): ax.imshow(gradient, aspect="auto", cmap=get_colormap(value)) ax.text( -0.01, 0.5, name, va="center", ha="right", fontsize=10, transform=ax.transAxes, ) # Turn off *all* ticks & spines, not just the ones with colormaps. for ax in axs: ax.set_axis_off()

In [4]:

cmap_list = [
    ("COLORS.Blues", COLORS.Blues),
    ("COLORS.Greens", COLORS.Greens),
    ("COLORS.Oranges", COLORS.Oranges),
    ("COLORS.Purples", COLORS.Purples),
    ("COLORS.Reds", COLORS.Reds),
    ("COLORS.Sunset2", COLORS.Sunset2),
    ("COLORS.YlGnBu", COLORS.YlGnBu),
    ("COLORS.YlOrRd", COLORS.YlOrRd),
    ("COLORS.PuBuGn", COLORS.PuBuGn),
    ("COLORS.RdBu", COLORS.RdBu),
    ("COLORS.BrBG", COLORS.BrBG),
    ("COLORS.PuOr", COLORS.PuOr),
    ("COLORS.Spectral", COLORS.Spectral),
    ("COLORS.RdYlBu", COLORS.RdYlBu),
    ("COLORS.RdYlGn", COLORS.RdYlGn),
    ("COLORS.Pastel", COLORS.Pastel),
    ("COLORS.Set2", COLORS.Set2),
    ("COLORS.Accent", COLORS.Accent),
    ("COLORS.Dark2", COLORS.Dark2),
    ("COLORS.Paired", COLORS.Paired),
    ("COLORS.Set1", COLORS.Set1),
    ("COLORS.Greys", COLORS.Greys),
    ("COLORS.Viridis", COLORS.Viridis),
    ("COLORS.Cividis", COLORS.Cividis),
    ("COLORS.Inferno", COLORS.Inferno),
    ("COLORS.Plasma", COLORS.Plasma)
]

cmap_list = [ ("COLORS.Blues", COLORS.Blues), ("COLORS.Greens", COLORS.Greens), ("COLORS.Oranges", COLORS.Oranges), ("COLORS.Purples", COLORS.Purples), ("COLORS.Reds", COLORS.Reds), ("COLORS.Sunset2", COLORS.Sunset2), ("COLORS.YlGnBu", COLORS.YlGnBu), ("COLORS.YlOrRd", COLORS.YlOrRd), ("COLORS.PuBuGn", COLORS.PuBuGn), ("COLORS.RdBu", COLORS.RdBu), ("COLORS.BrBG", COLORS.BrBG), ("COLORS.PuOr", COLORS.PuOr), ("COLORS.Spectral", COLORS.Spectral), ("COLORS.RdYlBu", COLORS.RdYlBu), ("COLORS.RdYlGn", COLORS.RdYlGn), ("COLORS.Pastel", COLORS.Pastel), ("COLORS.Set2", COLORS.Set2), ("COLORS.Accent", COLORS.Accent), ("COLORS.Dark2", COLORS.Dark2), ("COLORS.Paired", COLORS.Paired), ("COLORS.Set1", COLORS.Set1), ("COLORS.Greys", COLORS.Greys), ("COLORS.Viridis", COLORS.Viridis), ("COLORS.Cividis", COLORS.Cividis), ("COLORS.Inferno", COLORS.Inferno), ("COLORS.Plasma", COLORS.Plasma) ]

Continuous scales

In [5]:

plot_color_gradients(cmap_list=cmap_list)

plot_color_gradients(cmap_list=cmap_list)

Discrete scales

In [6]:

# change the number of sections `n_sections`
plot_color_gradients(cmap_list=cmap_list, n_sections=10)

# change the number of sections `n_sections` plot_color_gradients(cmap_list=cmap_list, n_sections=10)