tests edit

src/mlpack/methods/ann/layer/subview.hpp

@@ -41,7 +41,7 @@ class Subview
    * @param begin Start index.
    * @param end End index.
    */
-  Subview(const arma::uword begin = 0, const arma::uword end = 0):
+  Subview(const size_t begin = 0, const size_t end = 0):
     begin(begin),
     end(end)
   {
@@ -58,11 +58,11 @@ class Subview
   template<typename InputType, typename OutputType>
   void Forward(InputType&& input, OutputType&& output)
   {
+   
     // Check if input has been selected as required.
     if ((input.n_rows != (end-begin+1)) && (end != 0))
     {
-      arma::uword cols = input.n_cols;
-      output = arma::mat(&input(begin), end - begin + 1, cols, false);
+      output = arma::mat(&input(begin), end - begin + 1, input.n_cols, false);
     }
     else
     {
@@ -80,16 +80,10 @@ class Subview
    * @param g The calculated gradient.
    */
   template<typename eT>
-  void Backward(arma::Mat<eT>&& input,
+  void Backward(arma::Mat<eT>&& /* input */,
                 arma::Mat<eT>&& gy,
                 arma::Mat<eT>&& g)
   {
-    // Check if input has been selected as required.
-    if ((input.n_rows != (end-begin+1)) && (end != 0))
-    {
-      arma::uword cols = input.n_cols;
-      input = arma::mat(&input(begin), end - begin + 1, cols, false);
-    }
     g = gy;
   }
 

src/mlpack/tests/ann_layer_test.cpp

@@ -1813,8 +1813,38 @@ BOOST_AUTO_TEST_CASE(SimpleSubviewLayerTest)
 
   // Test the Backward function.
   module.Backward(std::move(input), std::move(input), std::move(delta));
-  BOOST_REQUIRE_EQUAL(accu(delta), 10);
-  BOOST_REQUIRE_EQUAL(delta.n_rows, 10);
+  BOOST_REQUIRE_EQUAL(accu(delta), 20);
+  BOOST_REQUIRE_EQUAL(delta.n_rows, 20);
+}
+
+/**
+ * Subview index test.
+ */
+BOOST_AUTO_TEST_CASE(SubviewIndexTest)
+{
+  arma::mat outputEnd, outputMid, outputStart, input, delta;
+  input = arma::linspace<arma::vec>(1, 20, 20);
+
+  // Slicing from the initial indices.
+  Subview<> moduleStart(0, 9);
+  arma::mat subStart = arma::linspace<arma::vec>(1, 10, 10);
+
+  moduleStart.Forward(std::move(input), std::move(outputStart));
+  CheckMatrices(outputStart, subStart);
+
+  // Slicing from the mid indices.
+  Subview<> moduleMid(6, 15);
+  arma::mat subMid = arma::linspace<arma::vec>(7, 16, 10);
+
+  moduleMid.Forward(std::move(input), std::move(outputMid));
+  CheckMatrices(outputMid, subMid);
+
+  // Slicing from the end indices.
+  Subview<> moduleEnd(10, 19);
+  arma::mat subEnd = arma::linspace<arma::vec>(11, 20, 10);
+
+  moduleEnd.Forward(std::move(input), std::move(outputEnd));
+  CheckMatrices(outputEnd, subEnd);
 }
 
 BOOST_AUTO_TEST_SUITE_END();