Introduction to Plotly

What is Plotly?

Plotly creates interactive charts. Unlike matplotlib:

• You can zoom in/out
• Hover to see values
• Pan around the chart
• Export as image

Install Plotly

pip install plotly

Your First Interactive Chart

import plotly.express as px

# Simple line chart
fig = px.line(x=[1, 2, 3, 4, 5], y=[1, 4, 9, 16, 25])
fig.show()

Try hovering over the points!

Why Plotly?

Basic Chart Types

import plotly.express as px

# Line chart
px.line(x=[1,2,3], y=[1,4,9])

# Bar chart
px.bar(x=['A','B','C'], y=[10,20,15])

# Scatter plot
px.scatter(x=[1,2,3], y=[1,4,9])

With DataFrame

import plotly.express as px
import pandas as pd

df = pd.DataFrame({
    'Month': ['Jan', 'Feb', 'Mar', 'Apr'],
    'Sales': [100, 120, 115, 140]
})

fig = px.bar(df, x='Month', y='Sales', title='Monthly Sales')
fig.show()

Interactive Features

When you view a Plotly chart:

• Hover: See exact values
• Zoom: Click and drag to zoom
• Pan: Shift + drag to move
• Reset: Double-click to reset
• Download: Camera icon to save

Key Points

• plotly.express (px) is the easy way
• Charts are interactive by default
• Works great with pandas DataFrames
• fig.show() displays the chart
• Perfect for dashboards and web apps

What's Next?

Learn Plotly Express basics for creating charts quickly.