3D Scatter Plot Legend Error From KMeans "No Handles With Labels Found To Put In Legend"

I have plotted 3D scatter plot for a KMeans model which I had fitted for RFM analysis. I used KMeans model labels for 'color' groups. when I used legend(), it pops an error, 'No h

Solution 1:

The problem with your code is that you didn't provide any label for the scattered points, so there's no reason legend would work.

Following the Scatter plots with a legend tutorial on matplotlib's website, the following code randomize data with three "classes" and plot them with a legend:

from matplotlib import pyplot as plt
import numpy as np

fig = plt.figure(figsize=(8, 6))
ax = fig.add_subplot(111, projection='3d')

xs = np.random.normal(0, 1, (20,))
ys = np.random.normal(0, 1, (20,))
zs = np.random.normal(0, 1, (20,))

labels = np.random.choice(["First", "Second", "Third"], (20,))

for lbl in np.unique(labels):
    indices = np.where(labels == lbl)
    x = xs[indices]
    y = ys[indices]
    z = zs[indices]
    print(x,y,z,lbl)
    ax.scatter(x, y, z, s=50, alpha=0.6, label=str(lbl), cmap='rainbow')

ax.legend()

plt.show()

The result is: