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import random

def generate_new_particles(old_particles, weights):
N = len(old_particles)
new_particles = []
index = int(random.random() * N)
beta = 0.0
mw = max(weights)
for i in range(N):
beta += random.random() * 2.0 * mw
print "beta =", beta
while beta > weights[index]:
beta -= weights[index]
index = (index + 1) % N
print "\tbeta= %f, index = %d, weight = %f" % (beta, index, weights[index])
new_particles.append(old_particles[index])
return new_particles

if name == "main":
old_particles = [1, 2, 3, 4]
weights = [.3, 0, .4, .3]
new_particles = generate_new_particles(old_particles, weights)

print "old particles =", old_particles
print "weights =", old_particles
print "new particles =", new_particles

https://calebmadrigal.com/resampling-wheel-algorithm/