projection 3d points to sphere

projection 3d points to sphere.py

# Reference: https://github.com/cvqluu/Angular-Penalty-Softmax-Losses-Pytorch/blob/master/plotting.py#L1

import matplotlib.pyplot as plt
from matplotlib import cm, colors
from mpl_toolkits.mplot3d import Axes3D
import numpy as np


def plot(embeds, labels, fig_path='./example.pdf'):

    fig = plt.figure(figsize=(10,10))
    ax = fig.add_subplot(111, projection='3d')

    # Create a sphere
    r = 1
    pi = np.pi
    cos = np.cos
    sin = np.sin
    phi, theta = np.mgrid[0.0:pi:100j, 0.0:2.0*pi:100j]
    x = r*sin(phi)*cos(theta)
    y = r*sin(phi)*sin(theta)
    z = r*cos(phi)
    ax.plot_surface(
        x, y, z,  rstride=1, cstride=1, color='w', alpha=0.3, linewidth=0)
    ax.scatter(embeds[:,0], embeds[:,1], embeds[:,2], c=labels, s=20)

    ax.set_xlim([-1, 1])
    ax.set_ylim([-1, 1])
    ax.set_zlim([-1, 1])
    ax.set_aspect("equal")
    plt.tight_layout()
    plt.savefig(fig_path)