xgboost/src/data/sparse_page_dmatrix.h
AbdealiJK 6f16f0ef58 Use bst_float consistently throughout (#1824)
* Fix various typos

* Add override to functions that are overridden

gcc gives warnings about functions that are being overridden by not
being marked as oveirridden. This fixes it.

* Use bst_float consistently

Use bst_float for all the variables that involve weight,
leaf value, gradient, hessian, gain, loss_chg, predictions,
base_margin, feature values.

In some cases, when due to additions and so on the value can
take a larger value, double is used.

This ensures that type conversions are minimal and reduces loss of
precision.
2016-11-30 10:02:10 -08:00

132 lines
3.7 KiB
C++

/*!
* Copyright 2015 by Contributors
* \file simple_dmatrix.h
* \brief In-memory version of DMatrix.
* \author Tianqi Chen
*/
#ifndef XGBOOST_DATA_SPARSE_PAGE_DMATRIX_H_
#define XGBOOST_DATA_SPARSE_PAGE_DMATRIX_H_
#include <xgboost/base.h>
#include <xgboost/data.h>
#include <dmlc/threadediter.h>
#include <vector>
#include <algorithm>
#include <string>
#include "./sparse_batch_page.h"
#include "../common/common.h"
namespace xgboost {
namespace data {
class SparsePageDMatrix : public DMatrix {
public:
explicit SparsePageDMatrix(std::unique_ptr<DataSource>&& source,
const std::string& cache_info)
: source_(std::move(source)), cache_info_(cache_info) {
}
MetaInfo& info() override {
return source_->info;
}
const MetaInfo& info() const override {
return source_->info;
}
dmlc::DataIter<RowBatch>* RowIterator() override {
dmlc::DataIter<RowBatch>* iter = source_.get();
iter->BeforeFirst();
return iter;
}
bool HaveColAccess() const override {
return col_iter_.get() != nullptr;
}
const RowSet& buffered_rowset() const override {
return buffered_rowset_;
}
size_t GetColSize(size_t cidx) const override {
return col_size_[cidx];
}
float GetColDensity(size_t cidx) const override {
size_t nmiss = buffered_rowset_.size() - col_size_[cidx];
return 1.0f - (static_cast<float>(nmiss)) / buffered_rowset_.size();
}
bool SingleColBlock() const override {
return false;
}
dmlc::DataIter<ColBatch>* ColIterator() override;
dmlc::DataIter<ColBatch>* ColIterator(const std::vector<bst_uint>& fset) override;
void InitColAccess(const std::vector<bool>& enabled,
float subsample,
size_t max_row_perbatch) override;
/*! \brief page size 256 MB */
static const size_t kPageSize = 256UL << 20UL;
/*! \brief Maximum number of rows per batch. */
static const size_t kMaxRowPerBatch = 64UL << 10UL;
private:
// declare the column batch iter.
class ColPageIter : public dmlc::DataIter<ColBatch> {
public:
explicit ColPageIter(std::vector<std::unique_ptr<dmlc::SeekStream> >&& files);
virtual ~ColPageIter();
void BeforeFirst() override;
const ColBatch &Value() const override {
return out_;
}
bool Next() override;
// initialize the column iterator with the specified index set.
void Init(const std::vector<bst_uint>& index_set, bool load_all);
private:
// the temp page.
SparsePage* page_;
// internal clock ptr.
size_t clock_ptr_;
// data file pointer.
std::vector<std::unique_ptr<dmlc::SeekStream> > files_;
// page format.
std::vector<std::unique_ptr<SparsePage::Format> > formats_;
/*! \brief internal prefetcher. */
std::vector<std::unique_ptr<dmlc::ThreadedIter<SparsePage> > > prefetchers_;
// The index set to be loaded.
std::vector<bst_uint> index_set_;
// The index set by the outsiders
std::vector<bst_uint> set_index_set_;
// whether to load data dataset.
bool set_load_all_, load_all_;
// temporal space for batch
ColBatch out_;
// the pointer data.
std::vector<SparseBatch::Inst> col_data_;
};
/*!
* \brief Try to initialize column data.
* \return true if data already exists, false if they do not.
*/
bool TryInitColData();
// source data pointer.
std::unique_ptr<DataSource> source_;
// the cache prefix
std::string cache_info_;
/*! \brief list of row index that are buffered */
RowSet buffered_rowset_;
// count for column data
std::vector<size_t> col_size_;
// internal column iter.
std::unique_ptr<ColPageIter> col_iter_;
};
} // namespace data
} // namespace xgboost
#endif // XGBOOST_DATA_SPARSE_PAGE_DMATRIX_H_