September 2017 Update

Task/Statistics-Basic/Zkl/statistics-basic-3.zkl

@@ -0,0 +1,13 @@
+var pipe=Thread.Pipe(); // used to connect the two threads
+fcn{ while(1){ pipe.write((0.0).random(1.0)) } }.launch();  // generator
+fcn{    // consumer/calculator
+   N:=0; M:=SD:=sum:=ssum:=0.0;
+   while(1){
+      x:=pipe.read(); N+=1; sum+=x; ssum+=x*x;
+      M=sum/N; SD=(ssum/N - M*M).sqrt();
+      if(0==N%100000)
+	 println("N:%,10d  mean:%.5f std dev:%.5f".fmt(N,M,SD));
+   }
+}.launch();
+
+Atomic.sleep(60*60);  // wait because exiting the VM kills the threads