2022-05-23 00:16:32 +04:00

44 lines
1.2 KiB
Python

"""
Candlestick Chart
=================
A candlestick chart inspired from `Protovis <http://mbostock.github.io/protovis/ex/candlestick.html>`_.
This example shows the performance of the Chicago Board Options Exchange `Volatility Index <https://en.wikipedia.org/wiki/VIX>`_ (VIX)
in the summer of 2009. The thick bar represents the opening and closing prices,
while the thin bar shows intraday high and low prices; if the index closed higher on a given day, the bars are colored green rather than red.
"""
# category: other charts
import altair as alt
from vega_datasets import data
source = data.ohlc()
open_close_color = alt.condition("datum.open <= datum.close",
alt.value("#06982d"),
alt.value("#ae1325"))
base = alt.Chart(source).encode(
alt.X('date:T',
axis=alt.Axis(
format='%m/%d',
labelAngle=-45,
title='Date in 2009'
)
),
color=open_close_color
)
rule = base.mark_rule().encode(
alt.Y(
'low:Q',
title='Price',
scale=alt.Scale(zero=False),
),
alt.Y2('high:Q')
)
bar = base.mark_bar().encode(
alt.Y('open:Q'),
alt.Y2('close:Q')
)
rule + bar