Custom color of Plotly candlesticks

Question

Is it possible to define custom color for candlesticks? We would like to color them according to our own business rules, not "increasing" and "decreasing" rules, which Plotly applies by default.

Answer 1

To answer you initial question directly wrt:

Is it possible to define custom color for candlesticks?

From the information you've provided so far, and the lack of data and code provided, I can only interpret your question as:

How to apply different colors to different candlestick sizes or ranges between open and close.

Here's a plot that sets different thresholds for what is considered extreme upwards and downwards movements through:

df['change'] = df['AAPL.Close'] - df['AAPL.Open']
df_hi = df[df['change']>1.5]
df_lo = df[df['change']<-0.3]

Then, a "base" trace is set up from data that are not considered extreme with:

fig = go.Figure(go.Candlestick(x=df['Date'],
                open=df['AAPL.Open'], high=df['AAPL.High'],
                low=df['AAPL.Low'], close=df['AAPL.Close']))

And then two additional traces are added to include the movements that are considered extreme with:

# set up trace with extreme highs
fig.add_traces(go.Candlestick(x=df_hi['Date'],
                open=df_hi['AAPL.Open'], high=df_hi['AAPL.High'],
                low=df_hi['AAPL.Low'], close=df_hi['AAPL.Close']))

I will provide further explanations on how the colors are set if this is in fact what you're looking for. With this setup, you can also subset the different traces through the legend.

Plot:

Complete code:

import plotly.graph_objects as go
from plotly.subplots import make_subplots
import pandas as pd

# data
df = pd.read_csv('https://raw.githubusercontent.com/plotly/datasets/master/finance-charts-apple.csv')
df=df.tail(15)

df['change'] = df['AAPL.Close'] - df['AAPL.Open']
df_hi = df[df['change']>1.5]
df_lo = df[df['change']<-0.3]

not_hi = df[df.index.isin(df_hi.index)].index
not_lo = df[df.index.isin(df_lo.index)].index
df = df.drop(not_hi)
df = df.drop(not_lo)

# set up figure with values not high and not low
# include candlestick with rangeselector
fig = go.Figure(go.Candlestick(x=df['Date'],
                open=df['AAPL.Open'], high=df['AAPL.High'],
                low=df['AAPL.Low'], close=df['AAPL.Close']))

# set up trace with extreme highs
fig.add_traces(go.Candlestick(x=df_hi['Date'],
                open=df_hi['AAPL.Open'], high=df_hi['AAPL.High'],
                low=df_hi['AAPL.Low'], close=df_hi['AAPL.Close']))

# set up traces with extreme lows
fig.add_traces(go.Candlestick(x=df_lo['Date'],
                open=df_lo['AAPL.Open'], high=df_lo['AAPL.High'],
                low=df_lo['AAPL.Low'], close=df_lo['AAPL.Close']))


color_hi_fill = 'black'
color_hi_line = 'blue'

color_lo_fill = 'yellow'
color_lo_line = 'purple'

fig.data[1].increasing.fillcolor = color_hi_fill
fig.data[1].increasing.line.color = color_hi_line
fig.data[1].decreasing.fillcolor = 'rgba(0,0,0,0)'
fig.data[1].decreasing.line.color = 'rgba(0,0,0,0)'

fig.data[2].increasing.fillcolor = 'rgba(0,0,0,0)'
fig.data[2].increasing.line.color = 'rgba(0,0,0,0)'
fig.data[2].decreasing.fillcolor = color_lo_fill
fig.data[2].decreasing.line.color = color_lo_line

fig.show()