def sbx_int(parents, prob, eta_c, xl, xu):
k = 0
if parents.shape[0] == parents.size:
parents = parents.reshape(-1, 1)
child = np.full((parents.shape), np.nan)
for i in range(int(parents.shape[0] / 2)):
child[k] = (crossover(get_crossover("int_sbx",
prob=prob,
eta=eta_c,
prob_per_variable=1.0),
parents[k].reshape(1, -1),
parents[k + 1].reshape(1, -1),
xl=xl,
xu=xu))[0]
child[k + 1] = (crossover(get_crossover("int_sbx",
prob=prob,
eta=eta_c,
prob_per_variable=1.0),
parents[k].reshape(1, -1),
parents[k + 1].reshape(1, -1),
xl=xl,
xu=xu))[1]
k = k + 2
else:
child = np.full((parents.shape), np.nan)
for i in range(int(parents.shape[0] / 2)):
child[k] = (crossover(get_crossover("int_sbx",
prob=prob,
eta=eta_c,
prob_per_variable=1.0),
parents[k].reshape(1, -1),
parents[k + 1].reshape(1, -1),
xl=xl,
xu=xu))[0]
child[k + 1] = (crossover(get_crossover("int_sbx",
prob=prob,
eta=eta_c,
prob_per_variable=1.0),
parents[k].reshape(1, -1),
parents[k + 1].reshape(1, -1),
xl=xl,
xu=xu))[1]
k = k + 2
return child
def show(eta_cross):
a, b = np.full((5000, 1), 0.2), np.full((5000, 1), 0.8)
off = crossover(
get_crossover("real_sbx",
prob=1.0,
eta=eta_cross,
prob_per_variable=1.0), a, b)
plt.hist(off, range=(0, 1), bins=200, density=True, color="red")
plt.show()
def example_parents(n_matings, n_var):
a = np.arange(n_var)[None, :].repeat(n_matings, axis=0)
b = a + n_var
return a, b
def show(M):
plt.figure(figsize=(4, 4))
plt.imshow(M, cmap='Greys', interpolation='nearest')
plt.show()
n_matings, n_var = 100, 100
a, b = example_parents(n_matings, n_var)
print("One Point Crossover")
off = crossover(get_crossover("bin_one_point"), a, b)
show((off[:n_matings] != a[0]))
print("Two Point Crossover")
off = crossover(get_crossover("bin_two_point"), a, b)
show((off[:n_matings] != a[0]))
print("K Point Crossover (k=4)")
off = crossover(get_crossover("bin_k_point", n_points=4), a, b)
show((off[:n_matings] != a[0]))
##END POINT
import numpy as np from pymoo.interface import crossover from pymoo.operators.crossover.parent_centric_crossover import PCX from pymoo.visualization.scatter import Scatter X = np.eye(3) X[1] = [0.9, 0.1, 0.1] n_points = 1000 a = X[[0]].repeat(n_points, axis=0) b = X[[1]].repeat(n_points, axis=0) c = X[[2]].repeat(n_points, axis=0) obj = PCX(eta=0.1, zeta=0.1, impl="elementwise") _X = crossover(obj, a, c, b, xl=-1, xu=1) sc = Scatter() sc.add(_X, facecolor=None, edgecolor="blue", alpha=0.7) sc.add(X, s=100, color="red") sc.add(X.mean(axis=0), color="green", label="Centroid") sc.show()
from pymoo.interface import crossover
from pymoo.factory import get_crossover
import numpy as np
import matplotlib.pyplot as plt
def example_parents(n_matings, n_var):
a = np.arange(n_var)[None, :].repeat(n_matings, axis=0)
b = a + n_var
return a, b
def show(M):
plt.figure(figsize=(4,4))
plt.imshow(M, cmap='Greys', interpolation='nearest')
plt.xlabel("Variables")
plt.ylabel("Individuals")
plt.show()
n_matings, n_var = 10, 10
a,b = example_parents(n_matings,n_var)
#print(a,b)
print("One Point Crossover")
print(get_crossover("bin_one_point"))
off = crossover(get_crossover("bin_one_point"), a, b)
print(len(off))
#show((off[:n_matings] != a[0]))