various fix of page

src/io/io.cpp

@@ -38,7 +38,6 @@ DataMatrix* LoadDataMatrix(const char *fname, bool silent, bool savebuffer) {
 
 void SaveDataMatrix(const DataMatrix &dmat, const char *fname, bool silent) {
   if (!strcmp(fname + strlen(fname) - 5, ".page")) {    
-    
     DMatrixPage::Save(fname, dmat, silent);
     return;
   }
@@ -46,7 +45,9 @@ void SaveDataMatrix(const DataMatrix &dmat, const char *fname, bool silent) {
     const DMatrixSimple *p_dmat = static_cast<const DMatrixSimple*>(&dmat);
     p_dmat->SaveBinary(fname, silent);
   } else {
-    utils::Error("not implemented");
+    DMatrixSimple smat;
+    smat.CopyFrom(dmat);
+    smat.SaveBinary(fname, silent);
   }
 }
 

src/io/page_dmatrix-inl.hpp

@@ -32,7 +32,7 @@ struct RowBatchPage {
     const size_t dsize = row.length * sizeof(RowBatch::Entry);
     if (FreeBytes() < dsize+ sizeof(int)) return false;
     row_ptr(Size() + 1) = row_ptr(Size()) + row.length;    
-    memcpy(data_ptr(Size()) , row.data, dsize);
+    memcpy(data_ptr(row_ptr(Size())) , row.data, dsize);
     ++ data_[0];
     return true;    
   }
@@ -55,6 +55,11 @@ struct RowBatchPage {
     batch.ind_ptr = &rptr[0];
     return batch;
   }
+  /*! \brief get i-th row from the batch */
+  inline RowBatch::Inst operator[](size_t i) {
+    return RowBatch::Inst(data_ptr(0) + row_ptr(i), 
+                          static_cast<bst_uint>(row_ptr(i+1) - row_ptr(i)));
+  }
   /*!
    * \brief clear the page, cleanup the content
    */
@@ -77,7 +82,7 @@ struct RowBatchPage {
     return data_[0];
   }
   /*! \brief page size 64 MB */
-  static const size_t kPageSize = 64 << 18;
+  static const size_t kPageSize = 64 << 8;
 
  private:
   /*! \return number of elements */
@@ -112,7 +117,6 @@ class ThreadRowPageIterator: public utils::IIterator<RowBatch> {
     itr.BeforeFirst();
     isend_ = false;
     base_rowid_ = 0;
-    utils::Assert(this->LoadNextPage(), "ThreadRowPageIterator");
   }
   virtual bool Next(void) {
     if(!this->LoadNextPage()) return false;

src/io/simple_dmatrix-inl.hpp

@@ -44,8 +44,8 @@ class DMatrixSimple : public DataMatrix {
   }
   /*! \brief copy content data from source matrix */
   inline void CopyFrom(const DataMatrix &src) {
-    this->info = src.info;
     this->Clear();
+    this->info = src.info;
     // clone data content in thos matrix
     utils::IIterator<RowBatch> *iter = src.fmat()->RowIterator();
     iter->BeforeFirst();