new function to support LSTM Unit

tests/basis.cpp

@@ -1,4 +1,5 @@
 #include <NeuralNetwork/BasisFunction/Linear.h>
+#include <NeuralNetwork/BasisFunction/Product.h>
 
 #include <iostream>
 #include <cassert>
@@ -33,6 +34,14 @@ int main() {
 		assert(220.0==l.computeStreaming(w,w));
 		assert(220.0==l.compute(w,w));
 	}
+	{
+		NeuralNetwork::BasisFunction::Product l;
+		std::vector<float> w({0,0.501,1});
+		std::vector<float> i({0,0.2,0.3});
+
+		assert(l(w,i) > 0.05999);
+		assert(l(w,i) < 0.06001);
+	}
 /*
 	std::vector<float> w;
 	std::vector<float> i;
@@ -61,6 +70,5 @@ int main() {
 		std::cout << "SSE :" << diff.count() << " s\n";
 	}
 */
-	std::cout <<"OK" << std::endl;
 
 }