diff --git a/LinearAlgebra/Matrix.cs b/LinearAlgebra/Matrix.cs
index 21e2670..696c547 100644
--- a/LinearAlgebra/Matrix.cs
+++ b/LinearAlgebra/Matrix.cs
@@ -243,7 +243,7 @@ public class Matrix2 {
     public void UpdateSlice((uint start, uint stop) rowRange, (uint start, uint stop) colRange, Matrix2 m) {
         for (uint i = rowRange.start; i < rowRange.stop; i++) {
             for (uint j = colRange.start; j < colRange.stop; j++)
-                this.data[i, j] = m.data[i - rowRange.start, j - colRange.stop];
+                this.data[i, j] = m.data[i - rowRange.start, j - colRange.start];
         }
     }