save the kernel selection policy

shogun-toolbox · Jul 13, 2016 · 4d4625f · 4d4625f
1 parent cf21fd1
commit 4d4625f
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Showing 2 changed files with 62 additions and 46 deletions.
diff --git a/src/shogun/statistical_testing/KernelSelectionStrategy.cpp b/src/shogun/statistical_testing/KernelSelectionStrategy.cpp
@@ -50,12 +50,15 @@ struct CKernelSelectionStrategy::Self
 	Self();
 
 	KernelManager kernel_mgr;
+	std::unique_ptr<KernelSelection> policy;
 
 	EKernelSelectionMethod method;
 	bool weighted;
 	index_t num_runs;
 	float64_t alpha;
 
+	void init_policy(CMMD* estimator);
+
 	const static EKernelSelectionMethod default_method;
 	const static bool default_weighted;
 	const static index_t default_num_runs;
@@ -67,12 +70,56 @@ const bool CKernelSelectionStrategy::Self::default_weighted=false;
 const index_t CKernelSelectionStrategy::Self::default_num_runs=10;
 const float64_t CKernelSelectionStrategy::Self::default_alpha=0.5;
 
-CKernelSelectionStrategy::Self::Self()
+CKernelSelectionStrategy::Self::Self() : policy(nullptr), method(default_method),
+	weighted(default_weighted), num_runs(default_num_runs), alpha(default_alpha)
 {
-	method=default_method;
-	weighted=default_weighted;
-	num_runs=default_num_runs;
-	alpha=default_alpha;
+}
+
+void CKernelSelectionStrategy::Self::init_policy(CMMD* estimator)
+{
+	switch (method)
+	{
+	case KSM_MEDIAN_HEURISTIC:
+	{
+		REQUIRE(!weighted, "Weighted kernel selection is not possible with MEDIAN_HEURISTIC!\n");
+		auto distance=estimator->compute_distance();
+		policy=std::unique_ptr<MedianHeuristic>(new MedianHeuristic(kernel_mgr, distance));
+		SG_UNREF(distance);
+	}
+	break;
+	case KSM_MAXIMIZE_XVALIDATION:
+	{
+		REQUIRE(!weighted, "Weighted kernel selection is not possible with MAXIMIZE_XVALIDATION!\n");
+		policy=std::unique_ptr<MaxXValidation>(new MaxXValidation(kernel_mgr, estimator,
+			num_runs, alpha));
+	}
+	break;
+	case KSM_MAXIMIZE_MMD:
+	{
+		if (weighted)
+			policy=std::unique_ptr<WeightedMaxMeasure>(new WeightedMaxMeasure(kernel_mgr, estimator));
+		else
+			policy=std::unique_ptr<MaxMeasure>(new MaxMeasure(kernel_mgr, estimator));
+	}
+	break;
+	case KSM_MAXIMIZE_POWER:
+	{
+		if (weighted)
+			policy=std::unique_ptr<WeightedMaxTestPower>(new WeightedMaxTestPower(kernel_mgr, estimator));
+		else
+			policy=std::unique_ptr<MaxTestPower>(new MaxTestPower(kernel_mgr, estimator));
+	}
+	break;
+	default:
+	{
+		SG_SERROR("Unsupported kernel selection method specified! Accepted strategies are "
+			"MAXIMIZE_MMD (single, weighted), "
+			"MAXIMIZE_POWER (single, weighted), "
+			"MAXIMIZE_XVALIDATION (single) and "
+			"MEDIAN_HEURISTIC (single)!\n");
+	}
+	break;
+	}
 }
 
 CKernelSelectionStrategy::CKernelSelectionStrategy()
@@ -142,52 +189,20 @@ void CKernelSelectionStrategy::add_kernel(CKernel* kernel)
 
 CKernel* CKernelSelectionStrategy::select_kernel(CMMD* estimator)
 {
-	SG_DEBUG("Entering!\n");
 	auto num_kernels=self->kernel_mgr.num_kernels();
 	REQUIRE(num_kernels>0, "Number of kernels is 0. Please add kernels using add_kernel method!\n");
-
 	SG_DEBUG("Selecting kernels from a total of %d kernels!\n", num_kernels);
-	std::unique_ptr<KernelSelection> policy=nullptr;
 
-	switch (self->method)
-	{
-		case KSM_MEDIAN_HEURISTIC:
-			{
-				REQUIRE(!self->weighted, "Weighted kernel selection is not possible with MEDIAN_HEURISTIC!\n");
-				auto distance=estimator->compute_distance();
-				policy=std::unique_ptr<MedianHeuristic>(new MedianHeuristic(self->kernel_mgr, distance));
-				SG_UNREF(distance);
-//				estimator->set_train_test_ratio(0);
-			}
-			break;
-		case KSM_MAXIMIZE_XVALIDATION:
-			{
-				REQUIRE(!self->weighted, "Weighted kernel selection is not possible with MAXIMIZE_XVALIDATION!\n");
-				policy=std::unique_ptr<MaxXValidation>(new MaxXValidation(self->kernel_mgr, estimator,
-					self->num_runs, self->alpha));
-			}
-			break;
-		case KSM_MAXIMIZE_MMD:
-			if (self->weighted)
-				policy=std::unique_ptr<WeightedMaxMeasure>(new WeightedMaxMeasure(self->kernel_mgr, estimator));
-			else
-				policy=std::unique_ptr<MaxMeasure>(new MaxMeasure(self->kernel_mgr, estimator));
-			break;
-		case KSM_MAXIMIZE_POWER:
-			if (self->weighted)
-				policy=std::unique_ptr<WeightedMaxTestPower>(new WeightedMaxTestPower(self->kernel_mgr, estimator));
-			else
-				policy=std::unique_ptr<MaxTestPower>(new MaxTestPower(self->kernel_mgr, estimator));
-			break;
-		default:
-			SG_ERROR("Unsupported kernel selection method specified! "
-					"Presently only accepted values are MAXIMIZE_MMD, MAXIMIZE_POWER and MEDIAN_HEURISTIC!\n");
-			break;
-	}
+	self->init_policy(estimator);
+	ASSERT(self->policy!=nullptr);
+
+	return self->policy->select_kernel();
+}
 
-	ASSERT(policy!=nullptr);
-	SG_DEBUG("Leaving!\n");
-	return policy->select_kernel();
+void CKernelSelectionStrategy::erase_intermediate_results()
+{
+	self->policy=nullptr;
+	self->kernel_mgr.clear();
 }
 
 const char* CKernelSelectionStrategy::get_name() const

diff --git a/src/shogun/statistical_testing/KernelSelectionStrategy.h b/src/shogun/statistical_testing/KernelSelectionStrategy.h
@@ -75,6 +75,7 @@ class CKernelSelectionStrategy : public CSGObject
 	void add_kernel(CKernel* kernel);
 	CKernel* select_kernel(CMMD* estimator);
 	virtual const char* get_name() const;
+	void erase_intermediate_results();
 private:
 	struct Self;
 	std::unique_ptr<Self> self;