From f7698e2ac0b5a48bf6f0bdf442b78f4a83f23342 Mon Sep 17 00:00:00 2001
From: phpfs <phpfs@users.noreply.github.com>
Date: Wed, 5 May 2021 09:16:33 +0200
Subject: [PATCH] Fix calculation of total count

---
 app/src/pages/BinaryMetricsPage/BinaryMetricsPage.tsx | 6 +++---
 app/src/utils/numberOfDistinctPairs.ts                | 2 ++
 2 files changed, 5 insertions(+), 3 deletions(-)
 create mode 100644 app/src/utils/numberOfDistinctPairs.ts

diff --git a/app/src/pages/BinaryMetricsPage/BinaryMetricsPage.tsx b/app/src/pages/BinaryMetricsPage/BinaryMetricsPage.tsx
index 01f4444b..28dbf9a0 100644
--- a/app/src/pages/BinaryMetricsPage/BinaryMetricsPage.tsx
+++ b/app/src/pages/BinaryMetricsPage/BinaryMetricsPage.tsx
@@ -25,6 +25,7 @@ import { Store } from 'store/models';
 import { MetricsTuplesCategories } from 'types/MetricsTuplesCategories';
 import { TuplesLoader } from 'types/TuplesLoader';
 import { intersectionDescription } from 'utils/intersectionDescription';
+import { numberOfDistinctPairs } from 'utils/numberOfDistinctPairs';
 
 const getCountsByTuplesCategory = (
   store: Store,
@@ -118,9 +119,8 @@ const mapStateToProps = (state: Store): BinaryMetricsPageStateProps => ({
     state.BinaryMetricsStore.selectedDataView
   ),
   confusionMatrix: {
-    totalCount: Math.pow(
-      state.BenchmarkConfigurationStore.selectedDataset?.numberOfRecords ?? 0,
-      2
+    totalCount: numberOfDistinctPairs(
+      state.BenchmarkConfigurationStore.selectedDataset?.numberOfRecords ?? 0
     ),
     falseNegatives: getPairCountByTuplesCategory(
       state,
diff --git a/app/src/utils/numberOfDistinctPairs.ts b/app/src/utils/numberOfDistinctPairs.ts
new file mode 100644
index 00000000..2c0ccdf6
--- /dev/null
+++ b/app/src/utils/numberOfDistinctPairs.ts
@@ -0,0 +1,2 @@
+export const numberOfDistinctPairs = (size: number): number =>
+  (size * (size - 1)) / 2;