entendiendo_mds.py

#! /usr/bin/env pytho2
# -*- coding: utf-8 -2-
# vim:fenc=utf-8
#
# Copyright © 2022 adrian <adrian@arco>
#
# Distributed under terms of the MIT license.

"""
Representamos en 2d y 3d un número de puntos que entre ellos siempre están
a distancia 1.
"""

import numpy as np
import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D
from sklearn import manifold

mds2 = manifold.MDS(n_components=2, max_iter=3000, eps=1e-9, dissimilarity="precomputed", n_jobs=1)
mds3 = manifold.MDS(n_components=3, max_iter=3000, eps=1e-9, dissimilarity="precomputed", n_jobs=1)


# similarity matrix
sm3 = np.ones([3,3])
sm4 = np.ones([4,4])
sm5 = np.ones([5,5])
sm6 = np.ones([6,6])
sm7 = np.ones([7,7])
sm8 = np.ones([8,8])

sm3mds2 = mds2.fit(sm3).embedding_
sm4mds2 = mds2.fit(sm4).embedding_
sm5mds2 = mds2.fit(sm5).embedding_
sm6mds2 = mds2.fit(sm6).embedding_
sm7mds2 = mds2.fit(sm7).embedding_
sm8mds2 = mds2.fit(sm8).embedding_

sm3mds3 = mds3.fit(sm3).embedding_
sm4mds3 = mds3.fit(sm4).embedding_
sm5mds3 = mds3.fit(sm5).embedding_
sm6mds3 = mds3.fit(sm6).embedding_
sm7mds3 = mds3.fit(sm7).embedding_
sm8mds3 = mds3.fit(sm8).embedding_

fig2 = plt.figure()
fig2ax1 = fig2.add_subplot(2,3,1)
fig2ax2 = fig2.add_subplot(2,3,2)
fig2ax3 = fig2.add_subplot(2,3,3)
fig2ax4 = fig2.add_subplot(2,3,4)
fig2ax5 = fig2.add_subplot(2,3,5)
fig2ax6 = fig2.add_subplot(2,3,6)
fig2ax1.scatter(sm3mds2[:,0], sm3mds2[:,1])
fig2ax2.scatter(sm4mds2[:,0], sm4mds2[:,1])
fig2ax3.scatter(sm5mds2[:,0], sm5mds2[:,1])
fig2ax4.scatter(sm6mds2[:,0], sm6mds2[:,1])
fig2ax5.scatter(sm7mds2[:,0], sm7mds2[:,1])
fig2ax6.scatter(sm8mds2[:,0], sm8mds2[:,1])
plt.show()

fig3 = plt.figure()
fig3ax1 = fig3.add_subplot(2,3,1, projection='3d')
fig3ax2 = fig3.add_subplot(2,3,2, projection='3d')
fig3ax3 = fig3.add_subplot(2,3,3, projection='3d')
fig3ax4 = fig3.add_subplot(2,3,4, projection='3d')
fig3ax5 = fig3.add_subplot(2,3,5, projection='3d')
fig3ax6 = fig3.add_subplot(2,3,6, projection='3d')
fig3ax1.scatter(sm3mds3[:,0], sm3mds3[:,1], sm3mds3[:,2])
fig3ax2.scatter(sm4mds3[:,0], sm4mds3[:,1], sm4mds3[:,2])
fig3ax3.scatter(sm5mds3[:,0], sm5mds3[:,1], sm5mds3[:,2])
fig3ax4.scatter(sm6mds3[:,0], sm6mds3[:,1], sm6mds3[:,2])
fig3ax5.scatter(sm7mds3[:,0], sm7mds3[:,1], sm7mds3[:,2])
fig3ax6.scatter(sm8mds3[:,0], sm8mds3[:,1], sm8mds3[:,2])
plt.show()