Plot a circle with an edgecolor in Matplotlib

To plot a circle with an edgecolor in Matplotlib, you can use the Circle class from matplotlib.patches. This allows you to customize the circle's appearance including edge color and line width.

Steps to Create a Circle with Edgecolor

• Create a new figure using figure() method

• Add a subplot to the current axis

• Create a Circle instance with specified edgecolor and linewidth

• Add the circle patch to the plot

• Optionally add text using text() method

• Set axis limits and display the figure

Example

Here's how to create a circle with an orange edge ?

import matplotlib.pyplot as plt
import matplotlib.patches as patches

# Set figure size
plt.rcParams["figure.figsize"] = [7.00, 3.50]
plt.rcParams["figure.autolayout"] = True

# Create figure and axis
fig = plt.figure()
ax = fig.add_subplot(111)

# Create circle with orange edge
circle = patches.Circle((0, 0), radius=1, edgecolor="orange", linewidth=7, fill=False)
ax.add_patch(circle)

# Add text
plt.text(-0.25, 0, "Circle")

# Set axis limits and make axes equal
plt.xlim([-4, 4])
plt.ylim([-4, 4])
plt.axis('equal')

plt.show()

Customizing Circle Properties

You can customize various properties of the circle ?

import matplotlib.pyplot as plt
import matplotlib.patches as patches

fig, axes = plt.subplots(1, 3, figsize=(12, 4))

# Circle 1: Thick red edge
circle1 = patches.Circle((0, 0), radius=1, edgecolor="red", linewidth=5, fill=False)
axes[0].add_patch(circle1)
axes[0].set_title("Thick Red Edge")
axes[0].set_xlim([-2, 2])
axes[0].set_ylim([-2, 2])
axes[0].axis('equal')

# Circle 2: Filled with blue edge
circle2 = patches.Circle((0, 0), radius=1, edgecolor="blue", facecolor="lightblue", linewidth=3)
axes[1].add_patch(circle2)
axes[1].set_title("Filled with Blue Edge")
axes[1].set_xlim([-2, 2])
axes[1].set_ylim([-2, 2])
axes[1].axis('equal')

# Circle 3: Dashed green edge
circle3 = patches.Circle((0, 0), radius=1, edgecolor="green", linewidth=4, fill=False, linestyle='--')
axes[2].add_patch(circle3)
axes[2].set_title("Dashed Green Edge")
axes[2].set_xlim([-2, 2])
axes[2].set_ylim([-2, 2])
axes[2].axis('equal')

plt.tight_layout()
plt.show()

Key Parameters

Conclusion

Use matplotlib.patches.Circle with the edgecolor parameter to create circles with colored edges. Combine with linewidth and other properties to customize the appearance for your visualization needs.