TopolearnPlotly Express is the fastest way to an interactive chart and covers most everyday plotting.
Plotly Express functions take a DataFrame and column names:
px.scatter(df, x="gdpPercap", y="lifeExp")
px.line(df, x="date", y="price")
px.bar(df, x="country", y="pop")Each returns a complete Figure with axis titles taken from the column names, hover tooltips showing the mapped values, and a default theme. Display it with fig.show() in a notebook or script, or save it with fig.write_html(...).
Express accepts pandas DataFrames and, through the narwhals compatibility layer, also Polars and PyArrow tables. You can also pass plain lists or arrays: px.line(x=[1, 2, 3], y=[2, 4, 3]).
Common arguments shared by most functions:
title=,labels={"gdpPercap": "GDP per capita"}to rename columns in axis titles, legends and tooltips;log_x=True/log_y=True,range_x=[0, 10];width=,height=in pixels;template="plotly_white"for a lighter look.
px.line connects points in the order of the rows, so sort by x first. With y=["a", "b"] (several columns) Express draws one trace per column from wide-form data.
px.data ships sample datasets (gapminder, tips, iris, stocks) bundled with the library, handy for experimenting offline.
Example
import plotly.express as px
df = px.data.gapminder().query("year == 2007")
print(df.shape) # (142, 8)
fig = px.scatter(df, x="gdpPercap", y="lifeExp", log_x=True,
labels={"gdpPercap": "GDP per capita",
"lifeExp": "Life expectancy"},
title="Wealth and health, 2007")
print(fig.layout.xaxis.title.text) # GDP per capita
print(fig.layout.xaxis.type) # log
print(len(fig.data), fig.data[0].mode) # 1 markers
stocks = px.data.stocks()
fig2 = px.line(stocks, x="date", y=["GOOG", "AAPL"]) # wide form
print([t.name for t in fig2.data]) # ['GOOG', 'AAPL']
fig.write_html("gapminder.html")Remember
- px functions take a DataFrame plus column names and return a Figure
labels=renames columns everywhere they appear- Passing several y columns draws one trace per column
Watch out for
- Plotting unsorted data with
px.line, which connects rows in their given order.