add CLabels::as_binary converter

make some methods const, add copy constructors, add CBinaryLabels::from(...)

src/shogun/labels/BinaryLabels.cpp

@@ -10,13 +10,18 @@
 #include <shogun/labels/BinaryLabels.h>
 #include <shogun/mathematics/Statistics.h>
 #include <shogun/lib/SGVector.h>
+#include <shogun/base/range.h>
 
 using namespace shogun;
 
 CBinaryLabels::CBinaryLabels() : CDenseLabels()
 {
 }
 
+CBinaryLabels::CBinaryLabels(const CBinaryLabels& orig) : CDenseLabels(orig)
+{
+}
+
 CBinaryLabels::CBinaryLabels(int32_t num_labels) : CDenseLabels(num_labels)
 {
 }
@@ -149,3 +154,24 @@ CLabels* CBinaryLabels::shallow_subset_copy()
 
 	return shallow_copy_labels;
 }
+
+Some<CBinaryLabels> CBinaryLabels::from(const CDenseLabels* orig)
+{
+	auto labels = orig->get_labels();
+	for (auto i : range(labels.vlen))
+	{
+		if (!CMath::fequals(labels[i], 1.0, 0.0) && !CMath::fequals(labels[i], -1.0, 0.0))
+		{
+			SG_SERROR("Label at index %d (%f), but must be either +1.0 or -1.0.\n", i, labels[i])
+		}
+	}
+	auto result = Some<CBinaryLabels>::from_raw(new CBinaryLabels(labels));
+	result->set_values(orig->get_values());
+	return result;
+}
+
+Some<CBinaryLabels> CBinaryLabels::from(const CMulticlassLabels* orig)
+{
+	SG_SNOTIMPLEMENTED
+	return Some<CBinaryLabels>::from_raw(nullptr);
+}

src/shogun/labels/BinaryLabels.h

@@ -14,6 +14,7 @@
 #include <shogun/lib/common.h>
 #include <shogun/labels/LabelTypes.h>
 #include <shogun/labels/DenseLabels.h>
+#include <shogun/labels/MulticlassLabels.h>
 
 namespace shogun
 {
@@ -36,6 +37,9 @@ class CBinaryLabels : public CDenseLabels
 	/** default constructor */
 	CBinaryLabels();
 
+	/** Copy constructor */
+	CBinaryLabels(const CBinaryLabels& orig);
+
 	/** constructor
 	 *
 	 * @param num_labels number of labels
@@ -112,6 +116,11 @@ class CBinaryLabels : public CDenseLabels
 	{
 		return "BinaryLabels";
 	}
+
+#ifndef SWIG
+	static Some<CBinaryLabels> from(const CDenseLabels* orig);
+	static Some<CBinaryLabels> from(const CMulticlassLabels* orig);
+#endif // SWIG
 #ifndef SWIG // SWIG should skip this part
 	virtual CLabels* shallow_subset_copy();
 #endif

src/shogun/labels/DenseLabels.cpp

@@ -14,6 +14,7 @@
 #include <shogun/mathematics/Math.h>
 #include <shogun/mathematics/linalg/LinalgNamespace.h>
 
+
 using namespace shogun;
 
 CDenseLabels::CDenseLabels()
@@ -22,6 +23,12 @@ CDenseLabels::CDenseLabels()
 	init();
 }
 
+CDenseLabels::CDenseLabels(const CDenseLabels& orig) : CLabels(orig)
+{
+	init();
+	m_labels = orig.m_labels;
+}
+
 CDenseLabels::CDenseLabels(int32_t num_lab)
 : CLabels()
 {
@@ -77,15 +84,15 @@ void CDenseLabels::set_labels(SGVector<float64_t> v)
 	m_labels = v;
 }
 
-SGVector<float64_t> CDenseLabels::get_labels()
+SGVector<float64_t> CDenseLabels::get_labels() const
 {
 	if (m_subset_stack->has_subsets())
 		return get_labels_copy();
 
 	return m_labels;
 }
 
-SGVector<float64_t> CDenseLabels::get_labels_copy()
+SGVector<float64_t> CDenseLabels::get_labels_copy() const
 {
 	if (!m_subset_stack->has_subsets())
 		return m_labels.clone();
@@ -179,7 +186,7 @@ bool CDenseLabels::set_int_label(int32_t idx, int32_t label)
 		return false;
 }
 
-float64_t CDenseLabels::get_label(int32_t idx)
+float64_t CDenseLabels::get_label(int32_t idx) const
 {
 	int32_t real_num=m_subset_stack->subset_idx_conversion(idx);
 	ASSERT(m_labels.vector && idx<get_num_labels())

src/shogun/labels/DenseLabels.h

@@ -16,9 +16,11 @@
 #include <shogun/labels/Labels.h>
 #include <shogun/features/SubsetStack.h>
 
+
 namespace shogun
 {
 	class CFile;
+	class CBinaryLabels;
 
 /** @brief Dense integer or floating point labels
  *
@@ -34,6 +36,9 @@ class CDenseLabels : public CLabels
 		/** default constructor */
 		CDenseLabels();
 
+		/** Copy constructor */
+		CDenseLabels(const CDenseLabels& orig);
+
 		/** constructor
 		 *
 		 * @param num_labels number of labels
@@ -97,7 +102,7 @@ class CDenseLabels : public CLabels
 		 *
 		 * @return labels, a copy if a subset is set
 		 */
-		SGVector<float64_t> get_labels();
+		SGVector<float64_t> get_labels() const;
 
 		/** get label
 		 *
@@ -106,7 +111,7 @@ class CDenseLabels : public CLabels
 		 * @param idx index of label to get
 		 * @return value of label
 		 */
-		float64_t get_label(int32_t idx);
+		float64_t get_label(int32_t idx) const;
 
 		/** get label
 		 *
@@ -141,7 +146,7 @@ class CDenseLabels : public CLabels
 		 *
 		 * @return labels
 		 */
-		SGVector<float64_t> get_labels_copy();
+		SGVector<float64_t> get_labels_copy() const;
 
  		/** Getter for labels
 		 *
@@ -256,7 +261,9 @@ class CDenseLabels : public CLabels
 		 *
 		 * @return label type (binary, multiclass, ...)
 		 */
-		virtual ELabelType get_label_type() const=0;
+		virtual ELabelType get_label_type() const override { return LT_DENSE_GENERIC; }
+
+		virtual const char* get_name() const override { return "DenseLabels"; }
 
 	public:
 		/** label designates classify reject */

src/shogun/labels/LabelTypes.h

@@ -24,5 +24,7 @@ enum ELabelType
 	LT_LATENT = 5,
 	/// sparse label class for multilabel classification (sets of labels)
 	LT_SPARSE_MULTILABEL = 6,
+	/// generic dense labels type
+	LT_DENSE_GENERIC = 7
 };
 #endif

src/shogun/labels/Labels.cpp

@@ -6,6 +6,9 @@
  */
 
 #include <shogun/labels/Labels.h>
+#include <shogun/labels/DenseLabels.h>
+#include <shogun/labels/BinaryLabels.h>
+#include <shogun/labels/MulticlassLabels.h>
 #include <shogun/lib/common.h>
 #include <shogun/io/SGIO.h>
 
@@ -17,6 +20,13 @@ CLabels::CLabels()
 	init();
 }
 
+CLabels::CLabels(const CLabels& orig)
+{
+	m_current_values = orig.m_current_values;
+	m_subset_stack = orig.m_subset_stack;
+	SG_REF(m_subset_stack);
+}
+
 CLabels::~CLabels()
 {
 	SG_UNREF(m_subset_stack);
@@ -90,7 +100,31 @@ void CLabels::set_values(SGVector<float64_t> values)
 	m_current_values = values;
 }
 
-SGVector<float64_t> CLabels::get_values()
+SGVector<float64_t> CLabels::get_values() const
 {
 	return m_current_values;
 }
+
+Some<CBinaryLabels> CLabels::as_binary() const
+{
+	try
+	{
+		switch(get_label_type())
+		{
+		case LT_BINARY:
+			return Some<CBinaryLabels>::from_raw(new CBinaryLabels(*as<CBinaryLabels>()));
+		case LT_DENSE_GENERIC:
+			return CBinaryLabels::from(as<CDenseLabels>());
+		case LT_MULTICLASS:
+			return CBinaryLabels::from(as<CMulticlassLabels>());
+		default:
+			SG_NOTIMPLEMENTED
+		}
+	}
+	catch (const ShogunException& e)
+	{
+		SG_SERROR("Cannot convert %s to binary labels: \n", e.what(), get_name());
+	}
+
+	return Some<CBinaryLabels>::from_raw(nullptr);
+}

src/shogun/labels/Labels.h

@@ -12,6 +12,7 @@
 #include <shogun/lib/config.h>
 
 #include <shogun/lib/common.h>
+#include <shogun/base/some.h>
 #include <shogun/base/SGObject.h>
 #include <shogun/labels/LabelsFactory.h>
 #include <shogun/labels/LabelTypes.h>
@@ -20,6 +21,8 @@
 
 namespace shogun
 {
+class CBinaryLabels;
+
 /** @brief The class Labels models labels, i.e. class assignments of objects.
  *
  * Labels is the base class for general Label objects.
@@ -42,9 +45,17 @@ class CLabels : public CSGObject
 	/** default constructor */
 	CLabels();
 
+	/* Copy constructor */
+	CLabels(const CLabels& orig);
+
 	/** destructor */
 	virtual ~CLabels();
 
+
+#ifndef SWIG
+	/** Returns a new instance of labels of the specified type. */
+	virtual Some<CBinaryLabels> as_binary() const;
+#endif
 	/** Make sure the label is valid, otherwise raise SG_ERROR.
 	 *
 	 * possible with subset
@@ -122,7 +133,7 @@ class CLabels : public CSGObject
 	 *
 	 * @return confidences
 	 */
-	virtual SGVector<float64_t> get_values();
+	virtual SGVector<float64_t> get_values() const;
 
 #ifndef SWIG // SWIG should skip this part
 	virtual CLabels* shallow_subset_copy()