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pythondataframeplotlytrendline

Plotly Trendline for Line Chart

Is there any way to easily add a trendline to a plotly express line chart like there is for plotly scatter plot?

I have tried using this line to create my dataframe:

fig = px.line(df4, x=df4["DATE"], y=df4['Ratio'], title="Market Ratio", trendline='ols')

But it gives the error

TypeError: line() got an unexpected keyword argument 'trendline'

Thanks!

Solution

  • No, there isn't. And you don't need it. All you need is px.scatter and:

    fig.update_traces(mode = 'lines')

    This will yield the same result as px.line if it did have a trendline attribute.

    enter image description here

    Complete code:

    # imports
import pandas as pd
import plotly.express as px
import plotly.io as pio

# data
df = px.data.stocks()[['GOOG', 'AAPL']]

# your choices
target = 'GOOG'
colors = px.colors.qualitative.T10

# plotly
fig = px.scatter(df, 
                 x = target,
                 y = [c for c in df.columns if c != target],
                 template = 'plotly_dark',
                 color_discrete_sequence = colors,
                 trendline = 'ols',
                 title = "fig.update_traces(mode = 'lines')")
f = fig.full_figure_for_development(warn=False)
fig.update_traces(mode = 'lines')
fig.data[-1].line.color = 'red'
fig.show()