Parameter size_unit in geom_pie()

Use the size_unit parameter to relate the size of the "pie"\ to the length of the unit step along one of the axis.

import pandas as pd

from lets_plot import *

LetsPlot.setup_html()

mpg_df = pd.read_csv("https://raw.githubusercontent.com/JetBrains/lets-plot-docs/master/data/mpg.csv")
mpg_df.head(3)

	Unnamed: 0	manufacturer	model	displ	year	cyl	trans	drv	cty	hwy	fl	class
0	1	audi	a4	1.8	1999	4	auto(l5)	f	18	29	p	compact
1	2	audi	a4	1.8	1999	4	manual(m5)	f	21	29	p	compact
2	3	audi	a4	2.0	2008	4	manual(m6)	f	20	31	p	compact

ggplot(mpg_df) + geom_pie(aes(fill='class', weight='displ'))

1. Make Pie' Diameter Equal to the Unit Step along the X-axis

Parameters: size=1, size_unit="x".

ggplot(mpg_df) + \
    geom_pie(aes(fill='class', weight='displ'), size=1, size_unit="x") + \
    coord_fixed()

2. Decrease the Pie' Diameter Slightly

Parameters: size=0.7, size_unit="x".

ggplot(mpg_df) + \
    geom_pie(aes(fill='class', weight='displ'), size=0.7, size_unit="x") + \
    coord_fixed() + \
    theme_void()