Python Matplotlib Wind Barb Visualization

Introduction

In this tutorial, we will learn how to create wind barb plots using Python Matplotlib. Wind barbs are a graphical representation of wind speed and direction using a combination of flags, lines, and dots. The length of the line represents the wind speed, while the orientation of the flags and dots represent the wind direction.

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Import Libraries

First, we need to import the necessary libraries. In this case, we will be using the Matplotlib and NumPy libraries.

import matplotlib.pyplot as plt
import numpy as np

Create Data

Next, we will create the data that will be used to generate the wind barb plot. We will create a uniform grid of 5x5 and a vector field using the meshgrid and multiplication functions.

x = np.linspace(-5, 5, 5)
X, Y = np.meshgrid(x, x)
U, V = 12 * X, 12 * Y

Create Wind Barb Plot

Now, we can create the wind barb plot using the barbs function. We will use the default parameters to plot the uniform grid.

plt.barbs(X, Y, U, V)
plt.show()

Customize Wind Barb Plot

We can customize the wind barb plot by changing the parameters of the barbs function. For example, we can change the length and pivot point of the vectors, fill the circles for an empty barb, and change the colors of the flags and bars.

plt.barbs(X, Y, U, V, length=8, pivot='middle', fill_empty=True, rounding=False,
          sizes=dict(emptybarb=0.25, spacing=0.2, height=0.3), flagcolor='r',
          barbcolor=['b', 'g'], flip_barb=True, barb_increments=dict(half=10, full=20, flag=100))
plt.show()

Create Masked Wind Barb Plot

We can also create a masked wind barb plot by using a masked array. In this case, we will change the value of one vector to a bad value and mask it.

masked_u = np.ma.masked_array(U)
masked_u[4] = 1000  ## Bad value that should not be plotted when masked
masked_u[4] = np.ma.masked

plt.barbs(X, Y, masked_u, V, length=8, pivot='middle')
plt.show()

Summary

In this tutorial, we learned how to create wind barb plots using Python Matplotlib. We started by importing the necessary libraries and creating the data for the plot. We then created a basic wind barb plot and customized it by changing the parameters. Finally, we learned how to create a masked wind barb plot using a masked array.