refactored multi-kernel MMD (removed the distance instancen from there)

src/shogun/statistical_testing/QuadraticTimeMMD.cpp

@@ -558,18 +558,20 @@ SGVector<float64_t> CQuadraticTimeMMD::compute_statistic(const internal::KernelM
 
 	CDistance* distance=kernel_mgr.get_distance_instance();
 	SG_REF(distance);
+	kernel_mgr.set_precomputed_distance(compute_joint_distance(distance));
+	SG_UNREF(distance);
 
 	const index_t nx=get_num_samples_p();
 	const index_t ny=get_num_samples_q();
 
 	MultiKernelMMD compute(nx, ny, get_statistic_type());
-	compute.set_distance(compute_joint_distance(distance));
 	SGVector<float64_t> result=compute(kernel_mgr);
 
+	kernel_mgr.unset_precomputed_distance();
+
 	for (auto i=0; i<result.vlen; ++i)
 		result[i]=normalize_statistic(result[i]);
 
-	SG_UNREF(distance);
 	SG_DEBUG("Leaving");
 	return result;
 }

src/shogun/statistical_testing/internals/mmd/MultiKernelMMD.cpp

@@ -29,10 +29,8 @@
  */
 
 #include <shogun/io/SGIO.h>
-#include <shogun/lib/SGMatrix.h>
+#include <shogun/kernel/Kernel.h>
 #include <shogun/mathematics/Math.h>
-#include <shogun/kernel/ShiftInvariantKernel.h>
-#include <shogun/distance/CustomDistance.h>
 #include <shogun/statistical_testing/MMD.h>
 #include <shogun/statistical_testing/internals/KernelManager.h>
 #include <shogun/statistical_testing/internals/mmd/MultiKernelMMD.h>
@@ -52,11 +50,6 @@ MultiKernelMMD::MultiKernelMMD(index_t nx, index_t ny, EStatisticType stype) : n
 	SG_SDEBUG("number of samples are %d and %d!\n", n_x, n_y);
 }
 
-void MultiKernelMMD::set_distance(CCustomDistance* distance)
-{
-	m_distance=std::shared_ptr<CCustomDistance>(distance);
-}
-
 void MultiKernelMMD::add_term(terms_t& t, float32_t val, index_t i, index_t j) const
 {
 	if (i<n_x && j<n_x && i>=j)
@@ -124,8 +117,6 @@ float64_t MultiKernelMMD::compute_mmd(terms_t& t) const
 SGVector<float64_t> MultiKernelMMD::operator()(const KernelManager& kernel_mgr) const
 {
 	SG_SDEBUG("Entering!\n");
-	REQUIRE(m_distance, "Distance instace is not set!\n");
-	kernel_mgr.set_precomputed_distance(m_distance.get());
 
 	SGVector<float64_t> result(kernel_mgr.num_kernels());
 	std::vector<terms_t> terms(result.size());
@@ -149,7 +140,6 @@ SGVector<float64_t> MultiKernelMMD::operator()(const KernelManager& kernel_mgr)
 	}
 	terms.resize(0);
 
-	kernel_mgr.unset_precomputed_distance();
 	SG_SDEBUG("Leaving!\n");
 	return result;
 }

src/shogun/statistical_testing/internals/mmd/MultiKernelMMD.h

@@ -38,7 +38,6 @@ namespace shogun
 {
 
 template <typename T> class SGVector;
-class CCustomDistance;
 
 namespace internal
 {
@@ -51,15 +50,14 @@ class MultiKernelMMD
 public:
 	MultiKernelMMD(index_t nx, index_t ny, EStatisticType stype);
 	SGVector<float64_t> operator()(const KernelManager& kernel_mgr) const;
-	void set_distance(CCustomDistance* distance);
 private:
 	struct terms_t;
+	void add_term(terms_t&, float32_t, index_t, index_t) const;
+	float64_t compute_mmd(terms_t& t) const;
+
 	const index_t n_x;
 	const index_t n_y;
 	const EStatisticType s_type;
-	std::shared_ptr<CCustomDistance> m_distance;
-	void add_term(terms_t&, float32_t, index_t, index_t) const;
-	float64_t compute_mmd(terms_t& t) const;
 };
 
 }

tests/unit/statistical_testing/internals/MultiKernelMMD_unittest.cc

@@ -78,19 +78,19 @@ TEST(MultiKernelMMD, biased_full)
 	auto feats_p=gen_p->get_streamed_features(m);
 	auto feats_q=gen_q->get_streamed_features(n);
 
-	KernelManager kernel_mgr(num_kernels);
-	for (auto i=0, sigma=-5; i<num_kernels; ++i, sigma+=1)
-		kernel_mgr.kernel_at(i)=new CGaussianKernel(10, pow(2, sigma));
-
 	auto test=some<CTwoDistributionTestMock>();
 	test->set_p(feats_p);
 	test->set_q(feats_q);
 
+	KernelManager kernel_mgr(num_kernels);
+	for (auto i=0, sigma=-5; i<num_kernels; ++i, sigma+=1)
+		kernel_mgr.kernel_at(i)=new CGaussianKernel(10, pow(2, sigma));
+	auto distance=kernel_mgr.get_distance_instance();
+	kernel_mgr.set_precomputed_distance(test->compute_joint_distance(distance));
+
 	MultiKernelMMD tester(m, n, stype);
-	auto distance=some<CEuclideanDistance>();
-	distance->set_disable_sqrt(true);
-	tester.set_distance(test->compute_joint_distance(distance));
 	SGVector<float64_t> values=tester(kernel_mgr);
+	kernel_mgr.unset_precomputed_distance();
 
 	auto data_p=static_cast<CDenseFeatures<float64_t>*>(feats_p)->get_feature_matrix();
 	auto data_q=static_cast<CDenseFeatures<float64_t>*>(feats_q)->get_feature_matrix();
@@ -140,19 +140,19 @@ TEST(MultiKernelMMD, unbiased_full)
 	auto feats_p=gen_p->get_streamed_features(m);
 	auto feats_q=gen_q->get_streamed_features(n);
 
-	KernelManager kernel_mgr(num_kernels);
-	for (auto i=0, sigma=-5; i<num_kernels; ++i, sigma+=1)
-		kernel_mgr.kernel_at(i)=new CGaussianKernel(10, pow(2, sigma));
-
 	auto test=some<CTwoDistributionTestMock>();
 	test->set_p(feats_p);
 	test->set_q(feats_q);
 
+	KernelManager kernel_mgr(num_kernels);
+	for (auto i=0, sigma=-5; i<num_kernels; ++i, sigma+=1)
+		kernel_mgr.kernel_at(i)=new CGaussianKernel(10, pow(2, sigma));
+	auto distance=kernel_mgr.get_distance_instance();
+	kernel_mgr.set_precomputed_distance(test->compute_joint_distance(distance));
+
 	MultiKernelMMD tester(m, n, stype);
-	auto distance=some<CEuclideanDistance>();
-	distance->set_disable_sqrt(true);
-	tester.set_distance(test->compute_joint_distance(distance));
 	SGVector<float64_t> values=tester(kernel_mgr);
+	kernel_mgr.unset_precomputed_distance();
 
 	auto data_p=static_cast<CDenseFeatures<float64_t>*>(feats_p)->get_feature_matrix();
 	auto data_q=static_cast<CDenseFeatures<float64_t>*>(feats_q)->get_feature_matrix();
@@ -193,7 +193,7 @@ TEST(MultiKernelMMD, unbiased_incomplete)
 	const index_t n=8;
 	const index_t dim=1;
 	const float64_t difference=0.5;
-	const index_t num_kernels=1;
+	const index_t num_kernels=10;
 	const EStatisticType stype=ST_UNBIASED_INCOMPLETE;
 
 	auto gen_p=some<CMeanShiftDataGenerator>(0, dim, 0);
@@ -202,19 +202,19 @@ TEST(MultiKernelMMD, unbiased_incomplete)
 	auto feats_p=gen_p->get_streamed_features(m);
 	auto feats_q=gen_q->get_streamed_features(n);
 
-	KernelManager kernel_mgr(num_kernels);
-	for (auto i=0, sigma=-5; i<num_kernels; ++i, sigma+=1)
-		kernel_mgr.kernel_at(i)=new CGaussianKernel(10, pow(2, sigma));
-
 	auto test=some<CTwoDistributionTestMock>();
 	test->set_p(feats_p);
 	test->set_q(feats_q);
 
+	KernelManager kernel_mgr(num_kernels);
+	for (auto i=0, sigma=-5; i<num_kernels; ++i, sigma+=1)
+		kernel_mgr.kernel_at(i)=new CGaussianKernel(10, pow(2, sigma));
+	auto distance=kernel_mgr.get_distance_instance();
+	kernel_mgr.set_precomputed_distance(test->compute_joint_distance(distance));
+
 	MultiKernelMMD tester(m, n, stype);
-	auto distance=some<CEuclideanDistance>();
-	distance->set_disable_sqrt(true);
-	tester.set_distance(test->compute_joint_distance(distance));
 	SGVector<float64_t> values=tester(kernel_mgr);
+	kernel_mgr.unset_precomputed_distance();
 
 	auto data_p=static_cast<CDenseFeatures<float64_t>*>(feats_p)->get_feature_matrix();
 	auto data_q=static_cast<CDenseFeatures<float64_t>*>(feats_q)->get_feature_matrix();