Neue Klasse BinaryFeatureVector

cpp/subprojects/common/include/mlrl/common/input/feature_vector_binary.hpp

@@ -0,0 +1,22 @@
+/*
+ * @author Michael Rapp ([email protected])
+ */
+#pragma once
+
+#include "mlrl/common/input/feature_vector_nominal.hpp"
+
+/**
+ * A feature vector that stores the indices of all examples that are associated with the minority value, i.e., the least
+ * frequent value, of a binary feature.
+ */
+class BinaryFeatureVector final : public NominalFeatureVector {
+    public:
+
+        /**
+         * @param numElements   The number of elements in the vector, i.e., the number of examples associated with the
+         *                      minority value
+         * @param minorityValue The minority value, i.e., the least frequent value, of the binary feature
+         * @param majorityValue The majority value, i.e., the most frequent value, of the binary feature
+         */
+        BinaryFeatureVector(uint32 numElements, int32 minorityValue, int32 majorityValue);
+};

cpp/subprojects/common/include/mlrl/common/input/feature_vector_nominal.hpp

@@ -6,10 +6,10 @@
 #include "mlrl/common/input/feature_vector_common.hpp"
 
 /**
- * A feature vector that stores the indices of the examples that are associated with each value, except for the minority
- * value, i.e., the least frequent value, of a nominal feature.
+ * A feature vector that stores the indices of the examples that are associated with each value, except for the majority
+ * value, i.e., the most frequent value, of a nominal feature.
  */
-class NominalFeatureVector final : public AbstractFeatureVector {
+class NominalFeatureVector : public AbstractFeatureVector {
     private:
 
         int32* values_;
@@ -20,16 +20,17 @@ class NominalFeatureVector final : public AbstractFeatureVector {
 
         const uint32 numValues_;
 
-        const int32 minorityValue_;
+        const int32 majorityValue_;
 
     public:
 
         /**
-         * @param numValues     The number of distinct values of the nominal feature, excluding the minority value
-         * @param numExamples   The total number of examples
-         * @param minorityValue The minority value, i.e., the least frequent value, of the nominal feature
+         * @param numValues     The number of distinct values of the nominal feature, excluding the majority value
+         * @param numElements   The number of elements in the vector, i.e., the number of examples not associated with
+         *                      the majority value
+         * @param majorityValue The majority value, i.e., the most frequent value, of the nominal feature
          */
-        NominalFeatureVector(uint32 numValues, uint32 numExamples, int32 minorityValue);
+        NominalFeatureVector(uint32 numValues, uint32 numElements, int32 majorityValue);
 
         ~NominalFeatureVector() override;
 
@@ -45,13 +46,13 @@ class NominalFeatureVector final : public AbstractFeatureVector {
 
         /**
          * An iterator that provides access to the indices of the examples that are associated with each value of the
-         * nominal feature and allows to modify them.
+         * nominal feature, except for the majority value, and allows to modify them.
          */
         typedef uint32* index_iterator;
 
         /**
          * An iterator that provides read-only access to the indices of the examples that are associated with each value
-         * of the nominal feature.
+         * of the nominal feature, except for the majority value.
          */
         typedef const uint32* index_const_iterator;
 
@@ -127,26 +128,26 @@ class NominalFeatureVector final : public AbstractFeatureVector {
 
         /**
          * Returns an `indptr_iterator` to the beginning of the indices that specify the first element in the array of
-         * example indices that corresponds to each value of the nominal feature.
+         * example indices that corresponds to each value of the nominal feature, except for the majority value.
          *
          * @return An `indptr_iterator` to the beginning
          */
         indptr_iterator indptr_begin();
 
         /**
          * Returns an `indptr_iterator` to the end of the indices that specify the first element in the array of example
-         * indices that corresponds to each value of the nominal feature.
+         * indices that corresponds to each value of the nominal feature, except for the majority value.
          *
          * @return An `indptr_iterator` to the end
          */
         indptr_iterator indptr_end();
 
         /**
-         * Returns the minority value, i.e., the least frequent value, of the nominal feature.
+         * Returns the majority value, i.e., the least frequent value, of the nominal feature.
          *
-         * @return The minority value
+         * @return The majority value
          */
-        int32 getMinorityValue() const;
+        int32 getMajorityValue() const;
 
         uint32 getNumElements() const override;
 };

cpp/subprojects/common/include/mlrl/common/input/feature_vector_numerical.hpp

@@ -7,7 +7,8 @@
 #include "mlrl/common/input/feature_vector_common.hpp"
 
 /**
- * A feature vector that stores the values of training examples for a certain numerical feature.
+ * A feature vector that stores the values of training examples for a certain numerical feature, except for the examples
+ * associated with a sparse value.
  */
 class NumericalFeatureVector final : public AbstractFeatureVector {
     private:
@@ -19,7 +20,7 @@ class NumericalFeatureVector final : public AbstractFeatureVector {
     public:
 
         /**
-         * @param numElements   The number of elements in the vector
+         * @param numElements   The number of elements in the vector, excluding those associated with the sparse value
          * @param sparseValue   The value of sparse elements not explicitly stored in the vector
          */
         NumericalFeatureVector(uint32 numElements, float32 sparseValue);

cpp/subprojects/common/meson.build

@@ -40,6 +40,7 @@ source_files = [
     'src/mlrl/common/input/feature_type_numerical.cpp',
     'src/mlrl/common/input/feature_type_ordinal.cpp',
     'src/mlrl/common/input/feature_vector.cpp',
+    'src/mlrl/common/input/feature_vector_binary.cpp',
     'src/mlrl/common/input/feature_vector_common.cpp',
     'src/mlrl/common/input/feature_vector_equal.cpp',
     'src/mlrl/common/input/feature_vector_nominal.cpp',

cpp/subprojects/common/src/mlrl/common/input/feature_vector_binary.cpp

@@ -0,0 +1,7 @@
+#include "mlrl/common/input/feature_vector_binary.hpp"
+
+BinaryFeatureVector::BinaryFeatureVector(uint32 numElements, int32 minorityValue, int32 majorityValue)
+    : NominalFeatureVector(1, numElements, majorityValue) {
+    this->values_begin()[0] = minorityValue;
+    this->indptr_begin()[0] = 0;
+}

cpp/subprojects/common/src/mlrl/common/input/feature_vector_nominal.cpp

@@ -1,9 +1,9 @@
 #include "mlrl/common/input/feature_vector_nominal.hpp"
 
-NominalFeatureVector::NominalFeatureVector(uint32 numValues, uint32 numExamples, int32 minorityValue)
-    : values_(new int32[numValues]), indices_(new uint32[numExamples]), indptr_(new uint32[numValues + 1]),
-      numValues_(numValues), minorityValue_(minorityValue) {
-    indptr_[numValues] = numExamples;
+NominalFeatureVector::NominalFeatureVector(uint32 numValues, uint32 numElements, int32 majorityValue)
+    : values_(new int32[numValues]), indices_(new uint32[numElements]), indptr_(new uint32[numValues + 1]),
+      numValues_(numValues), majorityValue_(majorityValue) {
+    indptr_[numValues] = numElements;
 }
 
 NominalFeatureVector::~NominalFeatureVector() {
@@ -52,8 +52,8 @@ NominalFeatureVector::indptr_iterator NominalFeatureVector::indptr_end() {
     return &indptr_[numValues_];
 }
 
-int32 NominalFeatureVector::getMinorityValue() const {
-    return minorityValue_;
+int32 NominalFeatureVector::getMajorityValue() const {
+    return majorityValue_;
 }
 
 uint32 NominalFeatureVector::getNumElements() const {