diff --git a/src/CudaMatrix.cpp b/src/CudaMatrix.cpp
index 6108797..e17c779 100644
--- a/src/CudaMatrix.cpp
+++ b/src/CudaMatrix.cpp
@@ -1062,7 +1062,7 @@ bool CudaMatrix::setBlock(int aDim,int aBeginIndex, int aEndIndex, const CudaMat
         unaryCompare(this->getData(),aMatrix.getData(),data,this->getDataSize(),::NE);
         return out;
     }
-    float CudaMatrix::getValue(size_t index){
+    float CudaMatrix::getValue(size_t index) const{
         float result;
         cudaError_t cuda_error = cudaMemcpy(&result, getData() + index, sizeof(float), cudaMemcpyDeviceToHost);
 
diff --git a/src/CudaMatrix.h b/src/CudaMatrix.h
index 5daec9a..32a1fbb 100644
--- a/src/CudaMatrix.h
+++ b/src/CudaMatrix.h
@@ -113,7 +113,7 @@ namespace Aurora
         CudaMatrix operator!=(const CudaMatrix &aMatrix) const;
 
         // sub
-        float getValue(size_t index);
+        float getValue(size_t index) const;
         void setValue(size_t index, const float& value);
 
         /**