not need for the data_has_label parameters any more.

examples/binary_classification/predict.conf

@@ -4,5 +4,3 @@ task = predict
 data = binary.test
 
 input_model= LightGBM_model.txt
-
-data_has_label = true

examples/lambdarank/predict.conf

@@ -4,5 +4,3 @@ task = predict
 data = rank.test
 
 input_model= LightGBM_model.txt
-
-data_has_label = true

examples/parallel_learning/predict.conf

@@ -5,4 +5,3 @@ data = binary.test
 
 input_model= LightGBM_model.txt
 
-data_has_label = true

examples/regression/predict.conf

@@ -4,5 +4,3 @@ task = predict
 data = regression.test
 
 input_model= LightGBM_model.txt
-
-data_has_label = true

include/LightGBM/config.h

@@ -88,7 +88,6 @@ public:
   int max_bin = 255;
   int data_random_seed = 1;
   std::string data_filename = "";
-  bool data_has_label = true;
   std::vector<std::string> valid_data_filenames;
   std::string output_model = "LightGBM_model.txt";
   std::string output_result = "LightGBM_predict_result.txt";
@@ -274,8 +273,6 @@ struct ParameterAlias {
       { "app", "objective" },
       { "train_data", "data" },
       { "train", "data" },
-      { "has_label", "data_has_label" },
-      { "is_data_has_label", "data_has_label" },
       { "model_output", "output_model" },
       { "model_out", "output_model" },
       { "model_input", "input_model" },

include/LightGBM/dataset.h

@@ -208,9 +208,11 @@ public:
   /*!
   * \brief Create a object of parser, will auto choose the format depend on file
   * \param filename One Filename of data
+  * \param num_features Pass num_features of this data file if you know, <=0 means don't know
+  * \param has_label output, if num_features > 0, will output this data has label or not
   * \return Object of parser
   */
-  static Parser* CreateParser(const char* filename);
+  static Parser* CreateParser(const char* filename, int num_features, bool* has_label);
 };
 
 using PredictFunction =
@@ -299,6 +301,9 @@ public:
   /*! \brief Get Number of used features */
   inline int num_features() const { return num_features_; }
 
+  /*! \brief Get Number of total features */
+  inline int num_total_features() const { return num_total_features_; }
+
   /*! \brief Get Number of data */
   inline data_size_t num_data() const { return num_data_; }
 
@@ -373,6 +378,8 @@ private:
   std::vector<int> used_feature_map_;
   /*! \brief Number of used features*/
   int num_features_;
+  /*! \brief Number of total features*/
+  int num_total_features_;
   /*! \brief Number of total data*/
   data_size_t num_data_;
   /*! \brief Store some label level data*/

src/application/application.cpp

@@ -253,8 +253,7 @@ void Application::Train() {
 void Application::Predict() {
   // create predictor
   Predictor predictor(boosting_, config_.io_config.is_sigmoid);
-  predictor.Predict(config_.io_config.data_filename.c_str(),
-    config_.io_config.data_has_label, config_.io_config.output_result.c_str());
+  predictor.Predict(config_.io_config.data_filename.c_str(), config_.io_config.output_result.c_str());
   Log::Stdout("finish predict");
 }
 

src/application/predictor.hpp

@@ -96,7 +96,7 @@ public:
   * \param has_label True if this data contains label
   * \param result_filename Filename of output result
   */
-  void Predict(const char* data_filename, bool has_label, const char* result_filename) {
+  void Predict(const char* data_filename, const char* result_filename) {
     FILE* result_file;
 
 #ifdef _MSC_VER
@@ -108,8 +108,8 @@ public:
     if (result_file == NULL) {
       Log::Stderr("predition result file %s doesn't exists", data_filename);
     }
-
-    Parser* parser = Parser::CreateParser(data_filename);
+    bool has_label = false;
+    Parser* parser = Parser::CreateParser(data_filename, num_features_, &has_label);
 
     if (parser == nullptr) {
       Log::Stderr("can regonise input data format, filename %s", data_filename);

src/boosting/gbdt.cpp

@@ -60,10 +60,7 @@ void GBDT::Init(const Dataset* train_data, const ObjectiveFunction* object_funct
   hessians_ = new score_t[num_data_];
 
   // get max feature index
-  for (int i = 0; i < train_data->num_features(); ++i) {
-    max_feature_idx_ = Common::Max<int>(max_feature_idx_,
-              train_data->FeatureAt(i)->feature_index());
-  }
+  max_feature_idx_ = train_data_->num_total_features() - 1;
 
   // if need bagging, create buffer
   if (gbdt_config_->bagging_fraction < 1.0 && gbdt_config_->bagging_freq > 0) {

src/io/config.cpp

@@ -15,11 +15,6 @@ void OverallConfig::Set(const std::unordered_map<std::string, std::string>& para
   GetInt(params, "num_threads", &num_threads);
   GetTaskType(params);
 
-  // prediction task, default not has label
-  if (task_type == TaskType::kPredict) {
-    io_config.data_has_label = false;
-  }
-
   GetBoostingType(params);
   GetObjectiveType(params);
   GetMetricType(params);
@@ -125,11 +120,6 @@ void OverallConfig::CheckParamConflict() {
                                                  TreeLearnerType::kDataParallelTreeLearner) {
     is_parallel_find_bin = true;
   }
-
-  if (task_type == TaskType::kTrain && io_config.data_has_label == false) {
-    Log::Stderr("Data should have label in training task");
-  }
-
 }
 
 void IOConfig::Set(const std::unordered_map<std::string, std::string>& params) {
@@ -141,7 +131,6 @@ void IOConfig::Set(const std::unordered_map<std::string, std::string>& params) {
     Log::Stderr("No training/prediction data, application quit");
   }
   GetInt(params, "num_model_predict", &num_model_predict);
-  GetBool(params, "data_has_label", &data_has_label);
   GetBool(params, "is_pre_partition", &is_pre_partition);
   GetBool(params, "is_enable_sparse", &is_enable_sparse);
   GetBool(params, "use_two_round_loading", &use_two_round_loading);

src/io/dataset.cpp

@@ -29,7 +29,7 @@ Dataset::Dataset(const char* data_filename, const char* init_score_filename,
     // load weight, query information and initilize score
     metadata_.Init(data_filename, init_score_filename);
     // create text parser
-    parser_ = Parser::CreateParser(data_filename_);
+    parser_ = Parser::CreateParser(data_filename_, 0, nullptr);
     if (parser_ == nullptr) {
       Log::Stderr("cannot recognise input data format, filename: %s", data_filename_);
     }
@@ -189,7 +189,7 @@ void Dataset::ConstructBinMappers(int rank, int num_machines, const std::vector<
 
   // -1 means doesn't use this feature
   used_feature_map_ = std::vector<int>(sample_values.size(), -1);
-
+  num_total_features_ = sample_values.size();
   // start find bins
   if (num_machines == 1) {
     std::vector<BinMapper*> bin_mappers(sample_values.size());
@@ -209,6 +209,7 @@ void Dataset::ConstructBinMappers(int rank, int num_machines, const std::vector<
                                              num_data_, is_enable_sparse_));
       } else {
         // if feature is trival(only 1 bin), free spaces
+        Log::Stdout("Warning: feture %d only contains one value, will ignore it", i);
         delete bin_mappers[i];
       }
     }

src/io/parser.cpp

@@ -20,7 +20,38 @@ void GetStatistic(const char* str, int* comma_cnt, int* tab_cnt, int* colon_cnt)
   }
 }
 
-Parser* Parser::CreateParser(const char* filename) {
+bool CheckHasLabelForLibsvm(std::string& str) {
+  str = Common::Trim(str);
+  auto pos_space = str.find_first_of(" \f\n\r\t\v");
+  auto pos_colon = str.find_first_of(":");
+  if (pos_colon == std::string::npos || pos_colon > pos_space) {
+    return true;
+  } else {
+    return false;
+  }
+}
+
+bool CheckHasLabelForTSV(std::string& str, int num_features) {
+  str = Common::Trim(str);
+  auto tokens = Common::Split(str.c_str(), '\t');
+  if (tokens.size() == num_features) {
+    return false;
+  } else {
+    return true;
+  }
+}
+
+bool CheckHasLabelForCSV(std::string& str, int num_features) {
+  str = Common::Trim(str);
+  auto tokens = Common::Split(str.c_str(), ',');
+  if (tokens.size() == num_features) {
+    return false;
+  } else {
+    return true;
+  }
+}
+
+Parser* Parser::CreateParser(const char* filename, int num_features, bool* has_label) {
   std::ifstream tmp_file;
   tmp_file.open(filename);
   if (!tmp_file.is_open()) {
@@ -44,29 +75,45 @@ Parser* Parser::CreateParser(const char* filename) {
   // Get some statistic from 2 line
   GetStatistic(line1.c_str(), &comma_cnt, &tab_cnt, &colon_cnt);
   GetStatistic(line2.c_str(), &comma_cnt2, &tab_cnt2, &colon_cnt2);
+  Parser* ret = nullptr;
   if (line2.size() == 0) {
     // if only have one line on file
     if (colon_cnt > 0) {
-      return new LibSVMParser();
+      ret =  new LibSVMParser();
+      if (num_features > 0 && has_label != nullptr) {
+        *has_label = CheckHasLabelForLibsvm(line1);
+      }
     } else if (tab_cnt > 0) {
-      return new TSVParser();
+      ret = new TSVParser();
+      if (num_features > 0 && has_label != nullptr) {
+        *has_label = CheckHasLabelForTSV(line1, num_features);
+      }
     } else if (comma_cnt > 0) {
-      return new CSVParser();
-    } else {
-      return nullptr;
-    }
+      ret = new CSVParser();
+      if (num_features > 0 && has_label != nullptr) {
+        *has_label = CheckHasLabelForCSV(line1, num_features);
+      }
+    } 
   } else {
     if (colon_cnt > 0 || colon_cnt2 > 0) {
-      return new LibSVMParser();
+      ret = new LibSVMParser();
+      if (num_features > 0 && has_label != nullptr) {
+        *has_label = CheckHasLabelForLibsvm(line1);
+      }
     }
     else if (tab_cnt == tab_cnt2 && tab_cnt > 0) {
-      return new TSVParser();
+      ret = new TSVParser();
+      if (num_features > 0 && has_label != nullptr) {
+        *has_label = CheckHasLabelForTSV(line1, num_features);
+      }
     } else if (comma_cnt == comma_cnt2 && comma_cnt > 0) {
-      return new CSVParser();
-    } else {
-      return nullptr;
+      ret = new CSVParser();
+      if (num_features > 0 && has_label != nullptr) {
+        *has_label = CheckHasLabelForCSV(line1, num_features);
+      }
     }
   }
+  return ret;
 }
 
 }  // namespace LightGBM