September 2017 Update

Task/Statistics-Basic/Zkl/statistics-basic-1.zkl

@@ -0,0 +1,4 @@
+fcn mean(ns)  { ns.sum(0.0)/ns.len() }
+fcn stdDev(ns){
+   m:=mean(ns); (ns.reduce('wrap(p,n){ x:=(n-m); p+x*x },0.0)/ns.len()).sqrt()
+}

Task/Statistics-Basic/Zkl/statistics-basic-2.zkl

@@ -0,0 +1,9 @@
+reg ns;
+foreach n in (T(100,1000,10000)){
+   ns=(0).pump(n,List,(0.0).random.fp(1.0));
+   println("N:%,6d  mean:%.5f std dev:%.5f".fmt(n,mean(ns),stdDev(ns)));
+}
+foreach r in ([0.0 .. 0.9, 0.1]){  // using the last data set (10000 randoms)
+   n:=ns.filter('wrap(x){ r<=x<(r+0.1) }).len();
+   println("%.2f..%.2f:%4d%s".fmt(r,r+0.1,n,"*"*(n/20)));
+}

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