helper.py

import matplotlib.font_manager
from IPython.core.display import HTML
from matplotlib.patches import Rectangle
import matplotlib.pyplot as plt
import matplotlib.colors as mcolors


def plot_colortable(colors, title, sort_colors=True, emptycols=0):
    """
    Display matplotlib named color options.
    """

    cell_width = 212
    cell_height = 22
    swatch_width = 48
    margin = 12
    topmargin = 40

    # Sort colors by hue, saturation, value and name
    if sort_colors is True:
        by_hsv = sorted((tuple(mcolors.rgb_to_hsv(mcolors.to_rgb(color))),
                         name)
                        for name, color in colors.items())
        names = [name for hsv, name in by_hsv]
    else:
        names = list(colors)

    n = len(names)
    ncols = 4 - emptycols
    nrows = n // ncols + int(n % ncols > 0)

    width = cell_width * 4 + 2 * margin
    height = cell_height * nrows + margin + topmargin
    dpi = 72

    fig, ax = plt.subplots(figsize=(width / dpi, height / dpi), dpi=dpi)
    fig.subplots_adjust(margin/width, margin/height,
                        (width-margin)/width, (height-topmargin)/height)
    ax.set_xlim(0, cell_width * 4)
    ax.set_ylim(cell_height * (nrows-0.5), -cell_height/2.)
    ax.yaxis.set_visible(False)
    ax.xaxis.set_visible(False)
    ax.set_axis_off()
    ax.set_title(title, fontsize=24, loc="left", pad=10)

    for i, name in enumerate(names):
        row = i % nrows
        col = i // nrows
        y = row * cell_height

        swatch_start_x = cell_width * col
        text_pos_x = cell_width * col + swatch_width + 7

        ax.text(text_pos_x, y, name, fontsize=14,
                horizontalalignment='left',
                verticalalignment='center')

        ax.add_patch(
            Rectangle(xy=(swatch_start_x, y-9), width=swatch_width,
                      height=18, facecolor=colors[name], edgecolor='0.7')
        )

    return fig


def get_plt_options(style_param=None):
    
    """
    Print out available matplotlib options.
    
    Parameters
    ----------
        param: A string corresponding to the matplotlib parameter of interest. Options include: 'fontname', 'color' (default: None).
    """
    
    if style_param == 'fontname':
        
        def make_html(fontname):
            return "<p>{font}: <span style='font-family:{font}; font-size: 24px;'>{font}</p>".format(font=fontname)
        
        code = "\n".join([make_html(font) for font in sorted(set([f.name for f in matplotlib.font_manager.fontManager.ttflist]))])

        return HTML("<div style='column-count: 2;'>{}</div>".format(code))
    
    elif style_param == 'color':

        plot_colortable(mcolors.BASE_COLORS, "Base Colors",
                        sort_colors=False, emptycols=1)
                        
        plot_colortable(mcolors.TABLEAU_COLORS, "Tableau Palette",
                        sort_colors=False, emptycols=2)

        plot_colortable(mcolors.CSS4_COLORS, "CSS Colors")

        plot_colortable(mcolors.XKCD_COLORS, "XKCD Colors")

        plt.show()
    
    else:
        return None