Refactoring

src/stats/precision.js

@@ -1,7 +1,7 @@
 import { getConfidenceInterval } from './confidence.js'
 import { getEnvDev } from './env_dev/main.js'
 import { getMoe, getRmoe } from './moe.js'
-import { getVariance, getStdev, getRstdev } from './variance.js'
+import { getVarianceStats } from './variance.js'
 
 // Retrieve stats related to `stdev` and precision.
 export const getPrecisionStats = function ({
@@ -22,9 +22,11 @@ export const getPrecisionStats = function ({
     return getPerfectPrecisionStats(mean)
   }
 
-  const variance = getVariance(measures, { minIndex, maxIndex, mean })
-  const stdev = getStdev(variance)
-  const rstdev = getRstdev(stdev, mean)
+  const { variance, stdev, rstdev } = getVarianceStats(measures, {
+    minIndex,
+    maxIndex,
+    mean,
+  })
 
   const { envDev } = getEnvDev(unsortedMeasures, {
     mean,

src/stats/variance.js

@@ -1,3 +1,14 @@
+// Retrieve all variance-related stats.
+// Rstdev is stdev relative to the mean.
+// This is more useful than stdev when comparing different combinations, or when
+// targetting a specific precision threshold.
+export const getVarianceStats = function (array, { minIndex, maxIndex, mean }) {
+  const variance = getVariance(array, { minIndex, maxIndex, mean })
+  const stdev = Math.sqrt(variance)
+  const rstdev = stdev / mean
+  return { variance, stdev, rstdev }
+}
+
 // Retrieve variance of an array of floats (cannot be NaN/Infinity).
 // Array must not be empty.
 // We use the absolute variance, as opposed to making it relative to the mean
@@ -29,15 +40,3 @@ const getSumDeviation = function ({ array, minIndex, maxIndex, mean }) {
 
   return sum
 }
-
-// Retrieve standard deviation
-export const getStdev = function (variance) {
-  return Math.sqrt(variance)
-}
-
-// Retrieve stdev relative to the mean.
-// This is more useful than stdev when comparing different combinations, or when
-// targetting a specific precision threshold.
-export const getRstdev = function (stdev, mean) {
-  return stdev / mean
-}