7.2 KiB
name, description
| name | description |
|---|---|
| plotly | Interactive scientific and statistical data visualization library for Python. Use when creating charts, plots, or visualizations including scatter plots, line charts, bar charts, heatmaps, 3D plots, geographic maps, statistical distributions, financial charts, and dashboards. Supports both quick visualizations (Plotly Express) and fine-grained customization (graph objects). Outputs interactive HTML or static images (PNG, PDF, SVG). |
Plotly
Python graphing library for creating interactive, publication-quality visualizations with 40+ chart types.
Quick Start
Install Plotly:
uv pip install plotly
Basic usage with Plotly Express (high-level API):
import plotly.express as px
import pandas as pd
df = pd.DataFrame({
'x': [1, 2, 3, 4],
'y': [10, 11, 12, 13]
})
fig = px.scatter(df, x='x', y='y', title='My First Plot')
fig.show()
Choosing Between APIs
Use Plotly Express (px)
For quick, standard visualizations with sensible defaults:
- Working with pandas DataFrames
- Creating common chart types (scatter, line, bar, histogram, etc.)
- Need automatic color encoding and legends
- Want minimal code (1-5 lines)
See reference/plotly-express.md for complete guide.
Use Graph Objects (go)
For fine-grained control and custom visualizations:
- Chart types not in Plotly Express (3D mesh, isosurface, complex financial charts)
- Building complex multi-trace figures from scratch
- Need precise control over individual components
- Creating specialized visualizations with custom shapes and annotations
See reference/graph-objects.md for complete guide.
Note: Plotly Express returns graph objects Figure, so you can combine approaches:
fig = px.scatter(df, x='x', y='y')
fig.update_layout(title='Custom Title') # Use go methods on px figure
fig.add_hline(y=10) # Add shapes
Core Capabilities
1. Chart Types
Plotly supports 40+ chart types organized into categories:
Basic Charts: scatter, line, bar, pie, area, bubble
Statistical Charts: histogram, box plot, violin, distribution, error bars
Scientific Charts: heatmap, contour, ternary, image display
Financial Charts: candlestick, OHLC, waterfall, funnel, time series
Maps: scatter maps, choropleth, density maps (geographic visualization)
3D Charts: scatter3d, surface, mesh, cone, volume
Specialized: sunburst, treemap, sankey, parallel coordinates, gauge
For detailed examples and usage of all chart types, see reference/chart-types.md.
2. Layouts and Styling
Subplots: Create multi-plot figures with shared axes:
from plotly.subplots import make_subplots
import plotly.graph_objects as go
fig = make_subplots(rows=2, cols=2, subplot_titles=('A', 'B', 'C', 'D'))
fig.add_trace(go.Scatter(x=[1, 2], y=[3, 4]), row=1, col=1)
Templates: Apply coordinated styling:
fig = px.scatter(df, x='x', y='y', template='plotly_dark')
# Built-in: plotly_white, plotly_dark, ggplot2, seaborn, simple_white
Customization: Control every aspect of appearance:
- Colors (discrete sequences, continuous scales)
- Fonts and text
- Axes (ranges, ticks, grids)
- Legends
- Margins and sizing
- Annotations and shapes
For complete layout and styling options, see reference/layouts-styling.md.
3. Interactivity
Built-in interactive features:
- Hover tooltips with customizable data
- Pan and zoom
- Legend toggling
- Box/lasso selection
- Rangesliders for time series
- Buttons and dropdowns
- Animations
# Custom hover template
fig.update_traces(
hovertemplate='<b>%{x}</b><br>Value: %{y:.2f}<extra></extra>'
)
# Add rangeslider
fig.update_xaxes(rangeslider_visible=True)
# Animations
fig = px.scatter(df, x='x', y='y', animation_frame='year')
For complete interactivity guide, see reference/export-interactivity.md.
4. Export Options
Interactive HTML:
fig.write_html('chart.html') # Full standalone
fig.write_html('chart.html', include_plotlyjs='cdn') # Smaller file
Static Images (requires kaleido):
uv pip install kaleido
fig.write_image('chart.png') # PNG
fig.write_image('chart.pdf') # PDF
fig.write_image('chart.svg') # SVG
For complete export options, see reference/export-interactivity.md.
Common Workflows
Scientific Data Visualization
import plotly.express as px
# Scatter plot with trendline
fig = px.scatter(df, x='temperature', y='yield', trendline='ols')
# Heatmap from matrix
fig = px.imshow(correlation_matrix, text_auto=True, color_continuous_scale='RdBu')
# 3D surface plot
import plotly.graph_objects as go
fig = go.Figure(data=[go.Surface(z=z_data, x=x_data, y=y_data)])
Statistical Analysis
# Distribution comparison
fig = px.histogram(df, x='values', color='group', marginal='box', nbins=30)
# Box plot with all points
fig = px.box(df, x='category', y='value', points='all')
# Violin plot
fig = px.violin(df, x='group', y='measurement', box=True)
Time Series and Financial
# Time series with rangeslider
fig = px.line(df, x='date', y='price')
fig.update_xaxes(rangeslider_visible=True)
# Candlestick chart
import plotly.graph_objects as go
fig = go.Figure(data=[go.Candlestick(
x=df['date'],
open=df['open'],
high=df['high'],
low=df['low'],
close=df['close']
)])
Multi-Plot Dashboards
from plotly.subplots import make_subplots
import plotly.graph_objects as go
fig = make_subplots(
rows=2, cols=2,
subplot_titles=('Scatter', 'Bar', 'Histogram', 'Box'),
specs=[[{'type': 'scatter'}, {'type': 'bar'}],
[{'type': 'histogram'}, {'type': 'box'}]]
)
fig.add_trace(go.Scatter(x=[1, 2, 3], y=[4, 5, 6]), row=1, col=1)
fig.add_trace(go.Bar(x=['A', 'B'], y=[1, 2]), row=1, col=2)
fig.add_trace(go.Histogram(x=data), row=2, col=1)
fig.add_trace(go.Box(y=data), row=2, col=2)
fig.update_layout(height=800, showlegend=False)
Integration with Dash
For interactive web applications, use Dash (Plotly's web app framework):
uv pip install dash
import dash
from dash import dcc, html
import plotly.express as px
app = dash.Dash(__name__)
fig = px.scatter(df, x='x', y='y')
app.layout = html.Div([
html.H1('Dashboard'),
dcc.Graph(figure=fig)
])
app.run_server(debug=True)
Reference Files
- plotly-express.md - High-level API for quick visualizations
- graph-objects.md - Low-level API for fine-grained control
- chart-types.md - Complete catalog of 40+ chart types with examples
- layouts-styling.md - Subplots, templates, colors, customization
- export-interactivity.md - Export options and interactive features
Additional Resources
- Official documentation: https://plotly.com/python/
- API reference: https://plotly.com/python-api-reference/
- Community forum: https://community.plotly.com/