Zoom and pan with toolbar in Matplotlib - Step-by-Step Execution

Concept Flow - Zoom and pan with toolbar

Start plot display

↓

User clicks zoom button

↓

Activate zoom mode

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User drags mouse to select area

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Plot zooms to selected area

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User clicks pan button

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Activate pan mode

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User drags plot to move view

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Plot view updates

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User clicks home button

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Plot resets to original view

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End interaction

The user interacts with the plot toolbar to zoom or pan the plot, changing the view dynamically.

Execution Sample

Matplotlib

import matplotlib.pyplot as plt

fig, ax = plt.subplots()
ax.plot([1, 2, 3, 4], [10, 20, 25, 30])
plt.show()

This code creates a simple line plot with a toolbar that allows zooming and panning.

Execution Table

Step	User Action	Toolbar Mode	Plot View Change	Output
1	Plot window opens	None	Full data range shown	Plot displayed with toolbar
2	Click zoom button	Zoom	Zoom mode activated	Cursor changes to zoom tool
3	Drag mouse to select area	Zoom	Plot zooms to selected rectangle	Plot view updates to zoomed area
4	Click pan button	Pan	Pan mode activated	Cursor changes to pan tool
5	Drag mouse to move plot	Pan	Plot view shifts accordingly	Plot view updates to new position
6	Click home button	None	Plot resets to original view	Plot view shows full data range
7	Close plot window	None	End interaction	Plot window closes

💡 User closes the plot window, ending interaction.

Variable Tracker

Variable	Start	After Step 3	After Step 5	Final
Toolbar Mode	None	Zoom	Pan	None
Plot View	Full range	Zoomed area	Shifted view	Full range

Key Moments - 2 Insights

Why does the cursor change when clicking zoom or pan buttons?

The cursor changes to indicate the active mode (zoom or pan), helping the user know what interaction is possible, as shown in execution_table steps 2 and 4.

What happens if you drag the mouse without selecting zoom or pan mode?

Dragging the mouse without activating zoom or pan does not change the plot view because no interaction mode is active, as seen before step 2 in the execution_table.

Visual Quiz - 3 Questions

Look at the execution table, what is the toolbar mode after step 3?

A Pan

B Zoom

C None

D Home

💡 Hint

Check the 'Toolbar Mode' column at step 3 in the execution_table.

At which step does the plot view reset to the original full data range?

A Step 6

B Step 5

C Step 3

D Step 7

💡 Hint

Look for 'Plot resets to original view' in the 'Plot View Change' column.

If the user never clicks the zoom or pan buttons, what will happen when dragging the mouse?

A Plot zooms in

B Plot pans

C No change in plot view

D Plot closes

💡 Hint

Refer to the key moment about dragging without activating zoom or pan mode.

Concept Snapshot

Zoom and pan with toolbar in matplotlib:
- Use toolbar buttons to activate zoom or pan modes.
- Drag mouse to zoom into or pan across the plot.
- Home button resets view to original.
- Cursor changes indicate active mode.
- Interaction updates plot view dynamically.

Full Transcript

This example shows how matplotlib's toolbar allows users to zoom and pan a plot interactively. When the plot window opens, the toolbar is inactive. Clicking the zoom button activates zoom mode, changing the cursor and allowing the user to drag a rectangle to zoom in. Clicking the pan button activates pan mode, letting the user drag the plot view around. The home button resets the plot to its original view. These interactions update the plot view dynamically, providing an intuitive way to explore data visually.