size_bar

Example demonstrating the SizeBar annotation for radial glyphs.

SizeBar provides a visual reference for understanding the size mapping in scatter plots where circle radius varies with data values.

import numpy as np

from bokeh.models import SizeBar
from bokeh.plotting import figure, show

N = 100
x = np.random.random(size=N) * 100
y = np.random.random(size=N) * 100
radii = np.random.random(size=N) * 10
colors = np.array([(r, g, 150) for r, g in zip(50 + 2*x, 30 + 2*y)], dtype=np.uint8)

p = figure()
cr = p.circle(x, y, radius=radii, fill_color=colors, fill_alpha=0.6, line_color=None)

size_bar = SizeBar(
    renderer=cr,
    title="SizeBar component",
    width="max",
    orientation="horizontal",
    glyph_fill_color="violet", glyph_fill_alpha=0.8, glyph_line_color="black",
    border_line_color="gray", border_line_dash="dotted",
)
p.add_layout(size_bar, "below")

show(p)