Data commit

Task/Active-object/Python/active-object.py

@@ -0,0 +1,38 @@
+from time import time, sleep
+from threading import Thread
+
+class Integrator(Thread):
+    'continuously integrate a function `K`, at each `interval` seconds'
+    def __init__(self, K=lambda t:0, interval=1e-4):
+        Thread.__init__(self)
+        self.interval  = interval
+        self.K   = K
+        self.S   = 0.0
+        self.__run = True
+        self.start()
+
+    def run(self):
+        "entry point for the thread"
+        interval = self.interval
+        start = time()
+        t0, k0 = 0, self.K(0)
+        while self.__run:
+            sleep(interval)
+            t1 = time() - start
+            k1 = self.K(t1)
+            self.S += (k1 + k0)*(t1 - t0)/2.0
+            t0, k0 = t1, k1
+
+    def join(self):
+        self.__run = False
+        Thread.join(self)
+
+if __name__ == "__main__":
+    from math import sin, pi
+
+    ai = Integrator(lambda t: sin(pi*t))
+    sleep(2)
+    print(ai.S)
+    ai.K = lambda t: 0
+    sleep(0.5)
+    print(ai.S)