1 files changed, 173 insertions, 0 deletions
diff --git a/PSO.py b/PSO.py
new file mode 100755
index 0000000..0d019cd
--- /dev/null
+++ b/PSO.py
@@ -0,0 +1,173 @@
+#!/usr/bin/env python3
+import time
+import random
+
+
+class Particle:
+    def __init__(self, x, y, z):
+        self.Pbest_x = 0
+        self.Pbest_y = 0
+        self.Pbest_z = 0
+        self.x = x
+        self.y = y
+        self.z = z
+        self.x_k1 = 0
+        self.y_k1 = 0
+        self.z_k1 = 0
+        self.V_x = 0
+        self.V_y = 0
+        self.V_z = 0
+        self.V_xk1 = 0
+        self.V_yk1 = 0
+        self.V_zk1 = 0
+
+    def __repr__(self):
+        return (
+            "{x: %s , y: %s, z: %s, Pbest_x: %s, Pbest_y: %s, Pbest_z: %s}\n"
+            % (
+                self.x,
+                self.y,
+                self.z,
+                self.Pbest_x,
+                self.Pbest_y,
+                self.Pbest_z,
+            )
+        )
+
+    def __str__(self):
+        return (
+            "{x: %s , y: %s, z: %s, Pbest_x: %s, Pbest_y: %s, Pbest_z: %s}\n"
+            % (
+                self.x,
+                self.y,
+                self.z,
+                self.Pbest_x,
+                self.Pbest_y,
+                self.Pbest_z,
+            )
+        )
+
+    def update_X(self):
+        self.x = self.x + self.V_xk1
+        self.y = self.y + self.V_yk1
+        self.z = self.z + self.V_zk1
+
+    def update_V(self, w, c1, c2, Gbest_x, Gbest_y, Gbest_z):
+        rand1 = random.random()
+        rand2 = random.random()
+        self.V_xk1 = (
+            w * self.V_x
+            + c1 * rand1 * (self.Pbest_x - self.x)
+            + c2 * rand2 * (Gbest_x - self.x)
+        )
+        self.V_yk1 = (
+            w * self.V_y
+            + c1 * rand1 * (self.Pbest_y - self.y)
+            + c2 * rand2 * (Gbest_y - self.y)
+        )
+        self.V_zk1 = (
+            w * self.V_z
+            + c1 * rand1 * (self.Pbest_z - self.z)
+            + c2 * rand2 * (Gbest_z - self.z)
+        )
+
+    def update_Pbest(self, x, y, z: float):
+        self.Pbest_x = x
+        self.Pbest_y = y
+        self.Pbest_z = z
+
+    def doRound(self, w, c1, c2, Gbest_x, Gbest_y, Gbest_z, fitness):
+        fitness_x = fitness(self.x, self.y, self.z)
+        self.update_V(w, c1, c2, Gbest_x, Gbest_y, Gbest_z)
+        self.update_X()
+        if abs(fitness(self.Pbest_x, self.Pbest_y, self.Pbest_z)) > abs(
+            fitness_x
+        ):
+            self.update_Pbest(self.x, self.y, self.z)
+
+
+class PSO:
+    def __init__(self, w, c1, c2, particle_count):
+        self.Gbest_x = 0
+        self.Gbest_y = 0
+        self.Gbest_z = 0
+        self.particle_count = particle_count
+        self.Particles = self.factory()
+        self.w = w
+        self.c1 = c1
+        self.c2 = c2
+
+    def factory(self):
+        result = list()
+        for _ in range(1, self.particle_count):
+            x = (
+                random.random() * 10
+                if random.random() > 0.5
+                else -random.random() * 10
+            )
+            y = (
+                random.random() * 10
+                if random.random() > 0.5
+                else -random.random() * 10
+            )
+            z = (
+                random.random() * 10
+                if random.random() > 0.5
+                else -random.random() * 10
+            )
+            result.append(Particle(x, y, z))
+        return result
+
+    def fitness(self, x, y, z: float):
+        return (
+            (x ** 5) - ((x ** 2) * y * z) + (z * x) + (y ** 2) - (z ** 3) - 10
+        )
+
+    def doRround(self):
+        roundBest_x = float()
+        roundBest_y = float()
+        roundBest_z = float()
+        for particle in self.Particles:
+            if abs(self.fitness(roundBest_x, roundBest_y, roundBest_z)) > abs(
+                self.fitness(particle.x, particle.y, particle.z)
+            ):
+                roundBest_x = particle.x
+                roundBest_y = particle.y
+                roundBest_z = particle.z
+        self.Gbest_x = roundBest_x
+        self.Gbest_y = roundBest_y
+        self.Gbest_z = roundBest_z
+        for particle in self.Particles:
+            particle.doRound(
+                self.w,
+                self.c1,
+                self.c2,
+                self.Gbest_x,
+                self.Gbest_y,
+                self.Gbest_z,
+                self.fitness,
+            )
+
+    def printGlobalBest(self):
+        print(
+            "x: %s, y: %s, z: %s, fitness: %s"
+            % (
+                self.Gbest_x,
+                self.Gbest_y,
+                self.Gbest_z,
+                self.fitness(self.Gbest_x, self.Gbest_y, self.Gbest_z),
+            ),
+        )
+
+
+def main():
+    random.seed(time.time())
+    round_count = 10
+    pso = PSO(5, 1.5, 1.5, 50)
+    for _ in range(1, round_count):
+        pso.doRround()
+    pso.printGlobalBest()
+
+
+if __name__ == "__main__":
+    main()