Data commit

Task/Active-object/D/active-object.d

@@ -0,0 +1,73 @@
+import core.thread;
+import std.datetime;
+import std.math;
+import std.stdio;
+
+void main() {
+    auto func = (double t) => sin(cast(double) PI * t);
+    Integrator integrator = new Integrator(func);
+    Thread.sleep(2000.msecs);
+
+    integrator.setFunc(t => 0.0);
+    Thread.sleep(500.msecs);
+
+    integrator.stop();
+    writeln(integrator.getOutput());
+}
+
+/**
+ * Integrates input function K over time
+ * S + (t1 - t0) * (K(t1) + K(t0)) / 2
+ */
+public class Integrator {
+    public alias Function = double function (double);
+
+    private SysTime start;
+    private shared bool running;
+
+    private Function func;
+    private shared double t0;
+    private shared double v0;
+    private shared double sum = 0.0;
+
+    public this(Function func) {
+        this.start = Clock.currTime();
+        setFunc(func);
+        new Thread({
+            integrate();
+        }).start();
+    }
+
+    public void setFunc(Function func) {
+        this.func = func;
+        v0 = func(0.0);
+        t0 = 0.0;
+    }
+
+    public double getOutput() {
+        return sum;
+    }
+
+    public void stop() {
+        running = false;
+    }
+
+    private void integrate() {
+        running = true;
+        while (running) {
+            Thread.sleep(1.msecs);
+            update();
+        }
+    }
+
+    private void update() {
+        import core.atomic;
+
+        Duration t1 = (Clock.currTime() - start);
+        double v1 = func(t1.total!"msecs");
+        double rect = (t1.total!"msecs" - t0) * (v0 + v1) / 2;
+        atomicOp!"+="(this.sum, rect);
+        t0 = t1.total!"msecs";
+        v0 = v1;
+    }
+}