add qid for dmlc#2748

include/xgboost/data.h

@@ -53,6 +53,8 @@ class MetaInfo {
  std::vector<bst_uint> group_ptr_;
  /*! \brief weights of each instance, optional */
  std::vector<bst_float> weights_;
+ /*! \brief session-id of each instance, optional */
+ std::vector<bst_float> qids;
  /*!
  * \brief initialized margins,
  * if specified, xgboost will start from this init margin

src/data/simple_csr_source.cc

@@ -26,6 +26,9 @@ void SimpleCSRSource::CopyFrom(DMatrix* src) {
 }
 
 void SimpleCSRSource::CopyFrom(dmlc::Parser<uint32_t>* parser) {
+ // use sessionID get gourp info
+ bst_float lastSessionId = -1.0;
+ bst_uint groupSizeAll = 0;
  this->Clear();
  while (parser->Next()) {
  const dmlc::RowBlock<uint32_t>& batch = parser->Value();
@@ -35,6 +38,22 @@ void SimpleCSRSource::CopyFrom(dmlc::Parser<uint32_t>* parser) {
  if (batch.weight != nullptr) {
  info.weights_.insert(info.weights_.end(), batch.weight, batch.weight + batch.size);
  }
+ if (batch.qid != nullptr) {
+ info.qids.insert(info.qids.end(), batch.qid, batch.qid + batch.size);
+ // get group
+ for (size_t i = 0; i < batch.size; ++i) {
+ bst_float curGroupId = batch.qid[i];
+ if (lastSessionId == -1) {
+ info.group_ptr.push_back(0);
+ }
+ else if (lastSessionId != curGroupId) {
+ info.group_ptr.push_back(groupSizeAll);
+ }
+ lastSessionId = curGroupId;
+ groupSizeAll++;
+ }
+ }
+
  // Remove the assertion on batch.index, which can be null in the case that the data in this
  // batch is entirely sparse. Although it's true that this indicates a likely issue with the
  // user's data workflows, passing XGBoost entirely sparse data should not cause it to fail.
@@ -56,6 +75,11 @@ void SimpleCSRSource::CopyFrom(dmlc::Parser<uint32_t>* parser) {
  page_.offset.push_back(page_.offset[top - 1] + batch.offset[i + 1] - batch.offset[0]);
  }
  }
+ if (lastSessionId != -1) {
+ if (groupSizeAll > info.group_ptr.back()) {
+ info.group_ptr.push_back(groupSizeAll);
+ }
+ }
  this->info.num_nonzero_ = static_cast<uint64_t>(page_.data.size());
 }