Color palettes

Examples of color palettes.

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import matplotlib.colors as mcolors
import matplotlib.pyplot as plt
import numpy as np
from matplotlib import patches

from plothist import get_color_palette


def create_palette_plot(
    colors: list[str] | list[tuple[float, float, float]],
    fig_name: str,
    add_text: bool = False,
    add_black_border: bool = False,
):
    ncolors = len(colors)

    # Create a figure and axis
    fig, ax = plt.subplots(figsize=(ncolors, 1))

    # Plot the colored squares with small spacing
    square_size = 1.0
    spacing = 0.1
    x = 0.0

    for color in colors:
        rect = patches.Rectangle((x, 0), square_size, square_size, color=color)
        ax.add_patch(rect)
        x += square_size + spacing

        if add_text:
            # Add text displaying the color value
            ax.text(
                x - (square_size + spacing) / 1.81,
                -0.18,
                mcolors.rgb2hex(color).upper(),
                ha="center",
                fontsize=10,
            )

    # Set the x-axis limits and show the ticks
    ax.set_xlim(-0.5, x - spacing)
    ax.set_xticks(np.arange(0, x, square_size + spacing))
    ax.set_xticklabels(np.arange(1, ncolors + 1), fontsize=8)
    ax.set_xticklabels([])  # Remove the x-tick labels

    # Set the y-axis ticks and labels
    ax.set_yticks([])
    ax.set_yticklabels([])

    # Remove the borders around the plot
    ax.spines["top"].set_visible(False)
    ax.spines["bottom"].set_visible(False)
    ax.spines["left"].set_visible(False)
    ax.spines["right"].set_visible(False)

    # Remove the x-label and y-label
    ax.set_xlabel("")
    ax.set_ylabel("")

    if add_black_border:
        # Add a black border rectangle
        border_rect = patches.Rectangle(
            (0, 0),
            x - spacing,
            square_size,
            edgecolor="black",
            facecolor="none",
            linewidth=1,
        )
        ax.add_patch(border_rect)

    # Adjust the padding and remove extra whitespace
    plt.margins(0)
    plt.gca().set_axis_off()
    plt.subplots_adjust(left=0.05, right=0.95)

    plt.savefig(fig_name, bbox_inches="tight")

    return fig


figs = []

ncolors = 7

ncolors_ggplot = 7 if ncolors > 7 else ncolors
colors = get_color_palette("ggplot", ncolors_ggplot)
figs.append(
    create_palette_plot(colors, fig_name="usage_style_cycle.svg", add_text=True)
)

colors = get_color_palette("cubehelix", ncolors)
figs.append(create_palette_plot(colors, fig_name="usage_cubehelix.svg"))

cmap_list = ["viridis", "coolwarm", "YlGnBu_r"]
for cmap_name in cmap_list:
    colors = get_color_palette(cmap_name, ncolors)
    figs.append(create_palette_plot(colors, fig_name=f"usage_{cmap_name}_palette.svg"))