diff --git a/modules/ml/include/opencv2/ml.hpp b/modules/ml/include/opencv2/ml.hpp
index da0cea8b9d..0b9026950e 100644
--- a/modules/ml/include/opencv2/ml.hpp
+++ b/modules/ml/include/opencv2/ml.hpp
@@ -224,11 +224,8 @@ public:
     CV_WRAP virtual void setTrainTestSplitRatio(double ratio, bool shuffle=true) = 0;
     CV_WRAP virtual void shuffleTrainTest() = 0;
 
-    CV_WRAP Mat getTestSamples() const {
-        Mat idx = getTestSampleIdx();
-        Mat samples = getSamples();
-        return idx.empty() ? Mat() : getSubVector(samples, idx);
-    }
+    /** @brief Returns matrix of test samples */
+    CV_WRAP Mat getTestSamples() const;
 
     CV_WRAP static Mat getSubVector(const Mat& vec, const Mat& idx);
 
diff --git a/modules/ml/src/data.cpp b/modules/ml/src/data.cpp
index a1608e3984..ad652568c7 100644
--- a/modules/ml/src/data.cpp
+++ b/modules/ml/src/data.cpp
@@ -50,6 +50,13 @@ static const int VAR_MISSED = VAR_ORDERED;
 
 TrainData::~TrainData() {}
 
+Mat TrainData::getTestSamples() const
+{
+    Mat idx = getTestSampleIdx();
+    Mat samples = getSamples();
+    return idx.empty() ? Mat() : getSubVector(samples, idx);
+}
+
 Mat TrainData::getSubVector(const Mat& vec, const Mat& idx)
 {
     if( idx.empty() )