Matplotlib Timer Objects | Programming Tutorials

Introduction

This lab aims to explain how to use general timer objects in Matplotlib. This is a simple example that is used to update the time placed in the title of the figure.

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Skills Graph

%%%%{init: {'theme':'neutral'}}%%%% flowchart RL matplotlib(("`Matplotlib`")) -.-> matplotlib/BasicConceptsGroup(["`Basic Concepts`"]) matplotlib(("`Matplotlib`")) -.-> matplotlib/PlottingDataGroup(["`Plotting Data`"]) python(("`Python`")) -.-> python/DataStructuresGroup(["`Data Structures`"]) python(("`Python`")) -.-> python/FunctionsGroup(["`Functions`"]) python(("`Python`")) -.-> python/ModulesandPackagesGroup(["`Modules and Packages`"]) python(("`Python`")) -.-> python/PythonStandardLibraryGroup(["`Python Standard Library`"]) python(("`Python`")) -.-> python/DataScienceandMachineLearningGroup(["`Data Science and Machine Learning`"]) matplotlib/BasicConceptsGroup -.-> matplotlib/importing_matplotlib("`Importing Matplotlib`") matplotlib/BasicConceptsGroup -.-> matplotlib/figures_axes("`Understanding Figures and Axes`") matplotlib/PlottingDataGroup -.-> matplotlib/line_plots("`Line Plots`") python/DataStructuresGroup -.-> python/tuples("`Tuples`") python/FunctionsGroup -.-> python/function_definition("`Function Definition`") python/ModulesandPackagesGroup -.-> python/importing_modules("`Importing Modules`") python/ModulesandPackagesGroup -.-> python/using_packages("`Using Packages`") python/ModulesandPackagesGroup -.-> python/standard_libraries("`Common Standard Libraries`") python/PythonStandardLibraryGroup -.-> python/date_time("`Date and Time`") python/DataScienceandMachineLearningGroup -.-> python/numerical_computing("`Numerical Computing`") python/DataScienceandMachineLearningGroup -.-> python/data_visualization("`Data Visualization`") subgraph Lab Skills matplotlib/importing_matplotlib -.-> lab-48997{{"`Using Matplotlib General Timer Objects`"}} matplotlib/figures_axes -.-> lab-48997{{"`Using Matplotlib General Timer Objects`"}} matplotlib/line_plots -.-> lab-48997{{"`Using Matplotlib General Timer Objects`"}} python/tuples -.-> lab-48997{{"`Using Matplotlib General Timer Objects`"}} python/function_definition -.-> lab-48997{{"`Using Matplotlib General Timer Objects`"}} python/importing_modules -.-> lab-48997{{"`Using Matplotlib General Timer Objects`"}} python/using_packages -.-> lab-48997{{"`Using Matplotlib General Timer Objects`"}} python/standard_libraries -.-> lab-48997{{"`Using Matplotlib General Timer Objects`"}} python/date_time -.-> lab-48997{{"`Using Matplotlib General Timer Objects`"}} python/numerical_computing -.-> lab-48997{{"`Using Matplotlib General Timer Objects`"}} python/data_visualization -.-> lab-48997{{"`Using Matplotlib General Timer Objects`"}} end

Import Required Libraries

Import the required libraries for the code to function properly.

from datetime import datetime
import matplotlib.pyplot as plt
import numpy as np

Define Function to Update Title

Define the function to update the title of the figure with the current time.

def update_title(axes):
    axes.set_title(datetime.now())
    axes.figure.canvas.draw()

Create Figure and Axes

Create a figure and axes for the plot.

fig, ax = plt.subplots()

Plot Data

Create data to plot and plot it on the axes.

x = np.linspace(-3, 3)
ax.plot(x, x ** 2)

Create Timer Object

Create a new timer object. Set the interval to 100 milliseconds (1000 is default) and tell the timer what function should be called.

timer = fig.canvas.new_timer(interval=100)
timer.add_callback(update_title, ax)

Start Timer

Start the timer.

timer.start()

Show Plot

Show the plot.

plt.show()

Summary

This lab showed how to use general timer objects in Matplotlib to update the time in the title of a figure. By following the steps, users can create their own timer objects and update their plots dynamically.

Using Matplotlib General Timer Objects