Introduction
In this lab, we will explore different ways to specify markers using Python Matplotlib. Markers are used to denote points on a graph and can be customized in various ways to enhance data visualization.
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Import libraries and set random seed
We will start by importing the necessary libraries and setting a random seed to ensure reproducibility of results.
import matplotlib.pyplot as plt
import numpy as np
## Set random seed
np.random.seed(19680801)
Generate random data
We will generate random data using NumPy's random module.
x = np.random.rand(10)
y = np.random.rand(10)
z = np.sqrt(x**2 + y**2)
Create subplots
We will create a 2x3 grid of subplots using subplots() function.
fig, axs = plt.subplots(2, 3, sharex=True, sharey=True, layout="constrained")
Customize markers
We will customize markers in the following ways:
Method 1: Matplotlib marker symbol
We will use the marker parameter to specify a Matplotlib marker symbol.
axs[0, 0].scatter(x, y, s=80, c=z, marker=">")
axs[0, 0].set_title("marker='>'")
Method 2: Marker from TeX
We will use the marker parameter to specify a marker from TeX by enclosing a TeX symbol name in $-signs.
axs[0, 1].scatter(x, y, s=80, c=z, marker=r"$\clubsuit$")
axs[0, 1].set_title(r"marker=r'\$\clubsuit\$'")
Method 3: Marker from path
We will use the marker parameter to specify a custom path of N vertices as a (N, 2) array-like.
verts = [[-1, -1], [1, -1], [1, 1], [-1, -1]]
axs[0, 2].scatter(x, y, s=80, c=z, marker=verts)
axs[0, 2].set_title("marker=verts")
Method 4: Regular polygon marker
We will use the marker parameter to specify a regular polygon marker using a tuple (N, 0).
axs[1, 0].scatter(x, y, s=80, c=z, marker=(5, 0))
axs[1, 0].set_title("marker=(5, 0)")
Method 5: Regular star marker
We will use the marker parameter to specify a regular star marker using a tuple (N, 1).
axs[1, 1].scatter(x, y, s=80, c=z, marker=(5, 1))
axs[1, 1].set_title("marker=(5, 1)")
Method 6: Regular asterisk marker
We will use the marker parameter to specify a regular asterisk marker using a tuple (N, 2).
axs[1, 2].scatter(x, y, s=80, c=z, marker=(5, 2))
axs[1, 2].set_title("marker=(5, 2)")
Show the plot
We will display the plot using show() function.
plt.show()
Summary
In this lab, we learned different ways to customize markers in Python Matplotlib. We explored various methods to specify markers and demonstrated their usage with code examples. By customizing markers, we can enhance the visual appeal of our data plots and make them more informative.