Three dimensions

Install required library

On Windows PowerShell:

py -m pip install matplotlib

On macOS or Linux:

python3 -m pip install matplotlib

Minimal example

This minimal example plots f(x, y) = e^{-(x2 + y2)} and shows it.

# Basic packages
import numpy as np
import matplotlib.pyplot as plt

# function
def f(x, y):
    return np.exp(-(x ** 2 + y ** 2))

# domain
x = np.linspace(-2.0, 2.0, 80)
y = np.linspace(-2.0, 2.0, 80)
X, Y = np.meshgrid(x, y)
Z = f(X, Y)

# visualization
fig = plt.figure(figsize=(6, 6))
ax = fig.add_subplot(projection="3d")
ax.plot_surface(X, Y, Z, cmap="viridis")
plt.show()

Complete example

This example plots f(x, y) = e^{-(x2 + y2)}, creates a figures folder next to the .py file, saves the figure, and then shows it.

# Basic packages
import numpy as np
import matplotlib.pyplot as plt
from pathlib import Path

# save path setting
script_dir = Path(__file__).resolve().parent
figures_dir = script_dir / "figures"
figures_dir.mkdir(exist_ok=True)

# function
def f(x, y):
    return np.exp(-(x ** 2 + y ** 2))

# domain
x = np.linspace(-2.0, 2.0, 80)
y = np.linspace(-2.0, 2.0, 80)
X, Y = np.meshgrid(x, y)
Z = f(X, Y)

# visualization
fig = plt.figure(figsize=(6, 6))
ax = fig.add_subplot(projection="3d")
ax.plot_surface(X, Y, Z, cmap="viridis")
ax.set_xlabel("$x$", fontsize=11)
ax.set_ylabel("$y$", fontsize=11)
ax.set_zlabel("$f(x, y)$", fontsize=11, labelpad=12)
ax.set_title("Surface plot of $f(x, y) = e^{-(x^2 + y^2)}$", fontsize=11, pad=14)
ax.view_init(elev=30, azim=45)

figure_path = figures_dir / "surface-3d.png"
fig.savefig(figure_path, dpi=300, bbox_inches="tight", pad_inches=0.2)
plt.show()

The script saves the figure as figures/surface-3d.png next to the .py file. This keeps generated figures close to the script that created them.

The resulting figure should look like this.