test: stddev

indutny · Mar 1, 2017 · 7086df2 · 7086df2
1 parent 3257c00
commit 7086df2
Showing 1 changed file with 24 additions and 5 deletions.
diff --git a/lib/test.js b/lib/test.js
@@ -35,7 +35,9 @@ function measure(json) {
 };
 
 let lavg = 0;
+let ldev = 0;
 let havg = 0;
+let hdev = 0;
 let count = 0;
 for (;;) {
   let low;
@@ -49,14 +51,31 @@ for (;;) {
   const jLow = genProbeJSON(postfix, low);
   const jHigh = genProbeJSON(postfix, high);
 
+  let lt;
+  let ht;
   if (Math.random() < 0.5) {
-    lavg += measure(jLow);
-    havg += measure(jHigh);
+    lt = measure(jLow);
+    ht = measure(jHigh);
   } else {
-    havg += measure(jHigh);
-    lavg += measure(jLow);
+    ht = measure(jLow);
+    lt = measure(jHigh);
   }
+  lavg += lt;
+  havg += lt;
+  ldev += Math.pow(lt, 2);
+  hdev += Math.pow(ht, 2);
   count++;
 
-  console.log('%d %d', (lavg / count).toFixed(1), (havg / count).toFixed(1));
+  let ltdev = ldev / count;
+  ltdev -= Math.pow(lavg / count, 2);
+  ltdev = Math.sqrt(ltdev);
+  let htdev = hdev / count;
+  htdev -= Math.pow(havg / count, 2);
+  htdev = Math.sqrt(htdev);
+
+  console.log('left=%d ldev=%d right=%d rdev=%d',
+              (lavg / count).toFixed(1),
+              ltdev.toFixed(1),
+              (havg / count).toFixed(1),
+              htdev.toFixed(1));
 }