add regression data

regression/xgboost_regdata.h

@@ -0,0 +1,132 @@
+#ifndef _XGBOOST_REGDATA_H_
+#define _XGBOOST_REGDATA_H_
+
+/*!
+ * \file xgboost_regdata.h
+ * \brief input data structure for regression and binary classification task.
+ *     Format:
+ *        The data should contain each data instance in each line.
+ *		  The format of line data is as below:
+ *        label <nonzero feature dimension> [feature index:feature value]+
+ * \author Kailong Chen: chenkl198812@gmail.com, Tianqi Chen: tianqi.tchen@gmail.com
+ */
+#include <cstdio>
+#include <vector>
+#include "../booster/xgboost_data.h"
+#include "../utils/xgboost_utils.h"
+#include "../utils/xgboost_stream.h"
+
+namespace xgboost{
+    namespace regression{
+        /*! \brief data matrix for regression content */
+        struct DMatrix{
+        public:
+            /*! \brief maximum feature dimension */
+            unsigned num_feature;
+            /*! \brief feature data content */
+            booster::FMatrixS data;
+            /*! \brief label of each instance */
+            std::vector<float> labels;
+        public:
+            /*! \brief default constructor */
+            DMatrix( void ){}
+            /*! 
+             * \brief load from text file 
+             * \param fname name of text data
+             * \param silent whether print information or not
+             */            
+            inline void LoadText( const char* fname, bool silent = false ){
+                data.Clear();
+                FILE* file = utils::FopenCheck( fname, "r" );
+                float label;
+                int nonzero_dimension;
+                std::vector<booster::bst_uint> findex;
+                std::vector<booster::bst_float> fvalue;
+                
+                while( fscanf(file,"%f %d",&label,&nonzero_dimension) == 2 ){
+                    findex.clear(); fvalue.clear();
+                    for( int i = 0; i < nonzero_dimension; i++ ){
+                        unsigned index; float value;
+                        utils::Assert( fscanf(file, "%d:%f", &index, &value ) == 2,                                      
+                                       "The feature dimension is not coincident with the indicated one" );
+                        findex.push_back(index); fvalue.push_back(value);
+                    }
+                    data.AddRow( findex, fvalue );
+                    labels.push_back( label );
+                }
+                this->UpdateInfo();
+                if( !silent ){
+                    printf("%ux%u matrix with %lu entries is loaded from %s\n", 
+                           (unsigned)labels.size(), num_feature, (unsigned long)data.NumEntry(), fname );
+                }
+                fclose(file);
+            }
+            /*! 
+             * \brief load from binary file 
+             * \param fname name of binary data
+             * \param silent whether print information or not
+             * \return whether loading is success
+             */
+            inline bool LoadBinary( const char* fname, bool silent = false ){
+                FILE *fp = fopen64( fname, "rb" );
+                if( fp == NULL ) return false;                
+                utils::FileStream fs( fp );
+                data.LoadBinary( fs );
+                labels.resize( data.NumRow() );
+                utils::Assert( fs.Read( &labels[0], sizeof(float) * data.NumRow() ) != 0, "DMatrix LoadBinary" );
+                fs.Close();
+                this->UpdateInfo();
+                if( !silent ){
+                    printf("%ux%u matrix with %lu entries is loaded from %s\n", 
+                           (unsigned)labels.size(), num_feature, (unsigned long)data.NumEntry(), fname );
+                }
+                return true;
+            }
+            /*! 
+             * \brief save to binary file
+             * \param fname name of binary data
+             * \param silent whether print information or not
+             */
+            inline void SaveBinary( const char* fname, bool silent = false ){
+                utils::FileStream fs( utils::FopenCheck( fname, "wb" ) );
+                data.SaveBinary( fs );
+                fs.Write( &labels[0], sizeof(float) * data.NumRow() );
+                fs.Close();
+                if( !silent ){
+                    printf("%ux%u matrix with %lu entries is saved to %s\n", 
+                           (unsigned)labels.size(), num_feature, (unsigned long)data.NumEntry(), fname );
+                }
+            }
+            /*! 
+             * \brief cache load data given a file name, the function will first check if fname + '.xgbuffer' exists,
+             *        if binary buffer exists, it will reads from binary buffer, otherwise, it will load from text file,
+             *        and try to create a buffer file 
+             * \param fname name of binary data
+             * \param silent whether print information or not
+             * \return whether loading is success
+             */            
+            inline void CacheLoad( const char *fname, bool silent = false ){
+                char bname[ 1024 ];
+                sprintf( bname, "%s.buffer", fname );
+                if( !this->LoadBinary( bname, silent ) ){
+                    this->LoadText( fname, silent );
+                    this->SaveBinary( fname, silent );
+                }                
+            }
+        private:
+            /*! \brief update num_feature info */
+            inline void UpdateInfo( void ){
+                this->num_feature = 0;
+                for( size_t i = 0; i < data.NumRow(); i ++ ){
+                    booster::FMatrixS::Line sp = data[i];
+                    for( unsigned j = 0; j < sp.len; j ++ ){
+                        if( num_feature <= sp.findex[j] ){
+                            num_feature = sp.findex[j] + 1;
+                        }
+                    }
+                }
+            }
+        };
+    };
+};
+#endif