diff --git a/src/shogun/lib/FibonacciHeap.cpp b/src/shogun/lib/FibonacciHeap.cpp
index 938380042db..3d87f3780ee 100644
--- a/src/shogun/lib/FibonacciHeap.cpp
+++ b/src/shogun/lib/FibonacciHeap.cpp
@@ -149,6 +149,19 @@ void CFibonacciHeap::clear()
 	num_trees = 0;
 }
 
+int32_t CFibonacciHeap::get_key(int32_t index, float64_t &ret_key)
+{
+	if(index > max_num_nodes || index < 0)
+		return -1;
+	if(nodes[index]->index == -1)
+		return -1;
+
+	int32_t result = nodes[index]->index;
+	ret_key = nodes[index]->key;
+
+	return result;
+}
+
 void CFibonacciHeap::decrease_key(int32_t index, float64_t key)
 {
 	FibonacciHeapNode* parent;
diff --git a/src/shogun/lib/FibonacciHeap.h b/src/shogun/lib/FibonacciHeap.h
index 1009b15a667..90d5e4769ba 100644
--- a/src/shogun/lib/FibonacciHeap.h
+++ b/src/shogun/lib/FibonacciHeap.h
@@ -100,6 +100,11 @@ class CFibonacciHeap: public CSGObject
 	 */
 	void clear();
 
+	/** Returns key by index.
+	 * @return -1 if not valid
+	 */
+	int32_t get_key(int32_t index, float64_t &ret_key);
+
 	/**
 	 */
 	void decrease_key(int32_t index, float64_t key);