From 0a7cfb32c6f453482bdc8a8f5fa4f2e2db1308fc Mon Sep 17 00:00:00 2001
From: tqchen <tianqi.tchen@gmail.com>
Date: Sun, 31 Aug 2014 21:58:01 -0700
Subject: [PATCH] add fmatrix, fight tmr

---
 src/io/page_dmatrix-inl.hpp |  1 +
 src/io/page_fmatrix-inl.hpp | 75 +++++++++++++++++++++++++++++++++++++
 2 files changed, 76 insertions(+)
 create mode 100644 src/io/page_fmatrix-inl.hpp

diff --git a/src/io/page_dmatrix-inl.hpp b/src/io/page_dmatrix-inl.hpp
index 8db944c85..23013b98b 100644
--- a/src/io/page_dmatrix-inl.hpp
+++ b/src/io/page_dmatrix-inl.hpp
@@ -9,6 +9,7 @@
 #include "../utils/iterator.h"
 #include "../utils/thread_buffer.h"
 #include "./simple_fmatrix-inl.hpp"
+#include "./page_fmatrix-inl.hpp"
 
 namespace xgboost {
 namespace io {
diff --git a/src/io/page_fmatrix-inl.hpp b/src/io/page_fmatrix-inl.hpp
new file mode 100644
index 000000000..156cddb63
--- /dev/null
+++ b/src/io/page_fmatrix-inl.hpp
@@ -0,0 +1,75 @@
+#ifndef XGBOOST_IO_PAGE_FMATRIX_INL_HPP_
+#define XGBOOST_IO_PAGE_FMATRIX_INL_HPP_
+/*!
+ * \file page_fmatrix-inl.hpp
+ * sparse page manager for fmatrix
+ * \author Tianqi Chen
+ */
+#include "../data.h"
+#include "../utils/iterator.h"
+#include "../utils/thread_buffer.h"
+namespace xgboost {
+namespace io {
+
+class CSCMatrixManager {
+ public:
+  /*! \brief in memory page */
+  struct Page {
+   public:
+    /*! \brief initialize the page */
+    inline void Init(size_t size) {
+      buffer.resize(size);
+      num_entry = 0;
+      col_index.clear();
+      col_data.clear();
+    }    
+    /*! \brief number of used entries */
+    size_t num_entry;
+    /*! \brief column index */
+    std::vector<bst_uint> col_index;
+    /*! \brief column data */
+    std::vector<ColBatch::Inst> col_data;            
+    /*! \brief number of free entries */
+    inline size_t NumFreeEntry(void) const {
+      return buffer.size() - num_entry;
+    }
+    inline ColBatch::Entry* AllocEntry(size_t len) {
+      ColBatch::Entry *p_data = &buffer[0] + num_entry;
+      num_entry += len;
+      return p_data;
+    }
+    /*! \brief get underlying batch */
+    inline ColBatch GetBatch(void) const {
+      ColBatch batch; 
+      batch.col_index = &col_index[0];
+      batch.col_data  = &col_data[0];
+      return batch;
+    }
+   private:
+    /*! \brief buffer space, not to be changed since ready */
+    std::vector<ColBatch::Entry> buffer;
+  };
+  
+ private:
+  /*! \brief fill a page with */
+  inline bool Fill(size_t cidx, Page *p_page) {
+    size_t len = col_ptr_[cidx+1] - col_ptr_[cidx];
+    if (p_page->NumFreeEntry() < len) return false;
+    ColBatch::Entry *p_data = p_page->AllocEntry(len);
+    fi->Seek(col_ptr_[cidx]);
+    utils::Check(fi->Read(p_data, sizeof(ColBatch::Entry) * len) != 0,
+                 "invalid column buffer format");
+    p_page->col_data.push_back(ColBatch::Inst(p_data, len));
+    p_page->col_index.push_back(cidx);
+  }
+  /*! \brief size of data content */
+  size_t data_size_;
+  /*! \brief input stream */
+  utils::ISeekStream *fi;
+  /*! \brief column pointer of CSC format */
+  std::vector<size_t> col_ptr_;  
+};
+
+}  // namespace io
+}  // namespace xgboost
+#endif  // XGBOOST_IO_PAGE_FMATRIX_INL_HPP_