Addition of the defaultValue property

app/engine/utils/WeighedSeries.js

@@ -2,13 +2,13 @@
 /*
   Open Rowing Monitor, https://github.com/laberning/openrowingmonitor
 
-  This creates a series with weights
-  It allows for determining the Average, Weighed Average, Median, Number of Positive, number of Negative
+  This creates a series with a maximum number of values
+  It allows for determining the Average, Median, Number of Positive, number of Negative
 */
 
 import { createSeries } from './Series.js'
 
-function createWeighedSeries (maxSeriesLength) {
+function createWeighedSeries (maxSeriesLength, defaultValue) {
   const dataArray = createSeries(maxSeriesLength)
   const weightArray = createSeries(maxSeriesLength)
   const weightedArray = createSeries(maxSeriesLength)
@@ -48,14 +48,20 @@ function createWeighedSeries (maxSeriesLength) {
   }
 
   function average () {
-    return dataArray.average()
+    if (dataArray.length() > 0) {
+      // The series contains sufficient values to be valid
+      return dataArray.average()
+    } else {
+      // The array isn't sufficiently filled
+      return defaultValue
+    }
   }
 
   function weighedAverage () {
     if (dataArray.length() > 0 && weightArray.sum() !== 0) {
       return (weightedArray.sum() / weightArray.sum())
     } else {
-      return undefined
+      return defaultValue
     }
   }
 
@@ -71,6 +77,10 @@ function createWeighedSeries (maxSeriesLength) {
     return dataArray.median()
   }
 
+  function reliable () {
+    return dataArray.length() > 0
+  }
+
   function series () {
     return dataArray.series()
   }
@@ -96,6 +106,7 @@ function createWeighedSeries (maxSeriesLength) {
     maximum,
     median,
     series,
+    reliable,
     reset
   }
 }