added block data structure

src/shogun/statistical_testing/internals/Block.cpp

@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) The Shogun Machine Learning Toolbox
+ * Written (w) 2016 Soumyajit De
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * The views and conclusions contained in the software and documentation are those
+ * of the authors and should not be interpreted as representing official policies,
+ * either expressed or implied, of the Shogun Development Team.
+ */
+
+#include <algorithm>
+#include <shogun/lib/SGVector.h>
+#include <shogun/features/Features.h>
+#include <shogun/statistical_testing/internals/Block.h>
+#include <shogun/statistical_testing/internals/FeaturesUtil.h>
+
+using namespace shogun;
+using namespace internal;
+
+Block::Block(CFeatures* feats, index_t index, index_t size) : m_feats(feats)
+{
+	REQUIRE(m_feats!=nullptr, "Underlying feature object cannot be null!\n");
+
+	// increase the refcount of the underlying feature object
+	// we want this object to be alive till the last block is free'd
+	SG_REF(m_feats);
+
+	// create a shallow copy and subset current block separately
+	CFeatures* block=FeaturesUtil::create_shallow_copy(feats);
+	ASSERT(block->ref_count()==0);
+
+	SGVector<index_t> inds(size);
+	std::iota(inds.vector, inds.vector+inds.vlen, index*size);
+	block->add_subset(inds);
+
+	// since this block object is internal, we simply use a shared_ptr
+	m_block=std::shared_ptr<CFeatures>(block);
+}
+
+Block::Block(const Block& other) : m_block(other.m_block), m_feats(other.m_feats)
+{
+	SG_REF(m_feats);
+}
+
+Block& Block::operator=(const Block& other)
+{
+	m_block=other.m_block;
+	m_feats=other.m_feats;
+	SG_REF(m_feats);
+	return *this;
+}
+
+Block::~Block()
+{
+	SG_UNREF(m_feats);
+}
+
+std::vector<Block> Block::create_blocks(CFeatures* feats, index_t num_blocks, index_t size)
+{
+	std::vector<Block> vec;
+	for (index_t i=0; i<num_blocks; ++i)
+		vec.push_back(Block(feats, i, size));
+	return vec;
+}

src/shogun/statistical_testing/internals/Block.h

@@ -0,0 +1,145 @@
+/*
+ * Copyright (c) The Shogun Machine Learning Toolbox
+ * Written (w) 2016 Soumyajit De
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * The views and conclusions contained in the software and documentation are those
+ * of the authors and should not be interpreted as representing official policies,
+ * either expressed or implied, of the Shogun Development Team.
+ */
+
+#include <memory>
+#include <vector>
+#include <shogun/lib/common.h>
+
+#ifndef BLOCK_H__
+#define BLOCK_H__
+
+namespace shogun
+{
+
+class CFeatures;
+
+namespace internal
+{
+
+/**
+ * @brief Class that holds a block feature. A block feature is a shallow
+ * copy of an underlying (non-owning) feature object. In its constructor,
+ * it increases the refcount of the original object (since it has to be
+ * alive as long as the block is alive) and it decreases the refcount of
+ * the original object in destructor.
+ */
+class Block
+{
+private:
+	/**
+	 * Constructor to create a block object. It makes a shallow copy of
+	 * the underlying feature object, and adds subset according to the
+	 * block begin index and the blocksize.
+	 *
+	 * Increases the reference count of the underlying feature object.
+	 *
+	 * @param feats The underlying feature object.
+	 * @param index The index of the block.
+	 * @param size The size of the block (number of feature vectors).
+	 */
+	Block(CFeatures* feats, index_t index, index_t size);
+public:
+	/**
+	 * Copy constructor. Every time a block is copied or assigned, the underlying
+	 * feature object is SG_REF'd.
+	 */
+	Block(const Block& other);
+
+	/**
+	 * Assignment operator. Every time a block is copied or assigned, the underlying
+	 * feature object is SG_REF'd.
+	 */
+	Block& operator=(const Block& other);
+
+	/**
+	 * Destructor. Decreases the reference count of the underlying feature object.
+	 */
+	~Block();
+
+	/**
+	 * Method that creates a number of block objects. See @Block for details.
+	 *
+	 * @param feats The underlying feature object.
+	 * @param num_blocks The number of blocks to be formed.
+	 * @param size The size of the block (number of feature vectors).
+	 */
+	static std::vector<Block> create_blocks(CFeatures* feats, index_t num_blocks, index_t size);
+
+	/**
+	 * Operator overloading for getting the block object as a shared ptr (non-const).
+	 */
+	inline operator std::shared_ptr<CFeatures>()
+	{
+		return m_block;
+	}
+
+	/**
+	 * Operator overloading for getting the block object as a naked ptr (non-const, unsafe).
+	 */
+	inline operator CFeatures*()
+	{
+		return m_block.get();
+	}
+
+	/**
+	 * Operator overloading for getting the block object as a naked ptr (const).
+	 */
+	inline operator const CFeatures*() const
+	{
+		return m_block.get();
+	}
+
+	/**
+	 * @return the block feature object (non-const, unsafe).
+	 */
+	inline CFeatures* get()
+	{
+		return static_cast<CFeatures*>(*this);
+	}
+
+	/**
+	 * @return the block feature object (const).
+	 */
+	inline const CFeatures* get() const
+	{
+		return static_cast<const CFeatures*>(*this);
+	}
+private:
+	/** Shallow copy representing the block */
+	std::shared_ptr<CFeatures> m_block;
+
+	/** Underlying feature object */
+	CFeatures* m_feats;
+};
+
+}
+
+}
+#endif // BLOCK_H__

tests/unit/statistical_testing/internals/Block_unittest.cc

@@ -0,0 +1,103 @@
+/*
+ * Copyright (c) The Shogun Machine Learning Toolbox
+ * Written (w) 2016 Soumyajit De
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * The views and conclusions contained in the software and documentation are those
+ * of the authors and should not be interpreted as representing official policies,
+ * either expressed or implied, of the Shogun Development Team.
+ */
+
+#include <shogun/lib/SGVector.h>
+#include <shogun/lib/SGMatrix.h>
+#include <shogun/features/Features.h>
+#include <shogun/features/DenseFeatures.h>
+#include <shogun/statistical_testing/internals/Block.h>
+#include <gtest/gtest.h>
+
+using namespace shogun;
+using namespace internal;
+
+TEST(Block, blocks)
+{
+	const index_t dim=3;
+	const index_t num_vec=8;
+	const index_t blocksize=2;
+
+	SGMatrix<float64_t> data_p(dim, num_vec);
+	std::iota(data_p.matrix, data_p.matrix+dim*num_vec, 0);
+
+	using feat_type=CDenseFeatures<float64_t>;
+	auto feats_p=new feat_type(data_p);
+
+	// check whether correct number of blocks has been formed
+	auto blocks=Block::create_blocks(feats_p, num_vec/blocksize, blocksize);
+	ASSERT_TRUE(blocks.size()==size_t(num_vec/blocksize));
+
+	// check const cast operator
+	for (auto it=blocks.begin(); it!=blocks.end(); ++it)
+	{
+		const Block& block=*it;
+		auto block_feats=static_cast<const CFeatures*>(block);
+		ASSERT_TRUE(block_feats->get_num_vectors()==blocksize);
+	}
+
+	// check non-const cast operator
+	for (auto it=blocks.begin(); it!=blocks.end(); ++it)
+	{
+		Block& block=*it;
+		auto block_feats=static_cast<std::shared_ptr<CFeatures>>(block);
+		ASSERT_TRUE(block_feats->get_num_vectors()==blocksize);
+	}
+
+	// check const get() method
+	for (auto it=blocks.begin(); it!=blocks.end(); ++it)
+	{
+		const Block& block=*it;
+		auto block_feats=block.get();
+		ASSERT_TRUE(block_feats->get_num_vectors()==blocksize);
+	}
+
+	// check non-const get() method
+	for (auto it=blocks.begin(); it!=blocks.end(); ++it)
+	{
+		Block& block=*it;
+		auto block_feats=block.get();
+		ASSERT_TRUE(block_feats->get_num_vectors()==blocksize);
+	}
+
+	// check for proper block-wise organizing
+	SGVector<index_t> inds(blocksize);
+	std::iota(inds.vector, inds.vector+inds.vlen, 0);
+	for (size_t i=0; i<blocks.size(); ++i)
+	{
+		feats_p->add_subset(inds);
+		SGMatrix<float64_t> subset=feats_p->get_feature_matrix();
+		SGMatrix<float64_t> blockd=static_cast<feat_type*>(blocks[i].get())->get_feature_matrix();
+		ASSERT_TRUE(subset.equals(blockd));
+		feats_p->remove_subset();
+		std::for_each(inds.vector, inds.vector+inds.vlen, [&blocksize](index_t& val) { val+=blocksize; });
+	}
+
+	// no clean-up should be required
+}