From b2c629123c5cf05afbeb19bd1424c327c1f5a606 Mon Sep 17 00:00:00 2001
From: Celian-abd <101793092+Celian-abd@users.noreply.github.com>
Date: Thu, 4 Jul 2024 04:10:47 +0200
Subject: [PATCH] fix: stdValue in TMTV mode (#4278)

---
 extensions/tmtv/src/commandsModule.ts | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/extensions/tmtv/src/commandsModule.ts b/extensions/tmtv/src/commandsModule.ts
index 75b264074..465b4b7a2 100644
--- a/extensions/tmtv/src/commandsModule.ts
+++ b/extensions/tmtv/src/commandsModule.ts
@@ -370,15 +370,16 @@ const commandsModule = ({ servicesManager, commandsManager, extensionManager }:
           voxelCount++;
         }
       }
+      const mean = segmentationValues.reduce((a, b) => a + b, 0) / voxelCount;
 
       const stats = {
         minValue: segmentationMin,
         maxValue: segmentationMax,
-        meanValue: segmentationValues.reduce((a, b) => a + b, 0) / voxelCount,
+        meanValue: mean,
         stdValue: Math.sqrt(
-          segmentationValues.reduce((a, b) => a + b * b, 0) / voxelCount -
-            segmentationValues.reduce((a, b) => a + b, 0) / voxelCount ** 2
-        ),
+          segmentationValues
+            .map((k) => (k - mean) ** 2)
+            .reduce((acc, curr) => acc + curr, 0) / voxelCount),
         volume: voxelCount * spacing[0] * spacing[1] * spacing[2] * 1e-3,
       };