overload several virtual functions to make ChunkEvaluator output multiple metrics

paddle/gserver/evaluators/ChunkEvaluator.cpp

@@ -16,6 +16,7 @@ limitations under the License. */
 #include <vector>
 
 #include "paddle/math/Vector.h"
+#include "paddle/utils/StringUtil.h"
 
 #include "Evaluator.h"
 
@@ -121,11 +122,9 @@ public:
   }
 
   virtual void printStats(std::ostream& os) const {
-    double precision = (double)numCorrect_ / numOutputSegments_;
-    double recall = (double)numCorrect_ / numLabelSegments_;
-    double f1 =
-        !numCorrect_ ? 0 : 2 * precision * recall / (precision + recall);
-    os << config_.name() << "=" << f1 << " true_chunks=" << numLabelSegments_
+    storeLocalValues();
+    os << config_.name() << "=" << values_["F1-score"]
+       << " true_chunks=" << numLabelSegments_
        << " result_chunks=" << numOutputSegments_
        << " correct_chunks=" << numCorrect_;
   }
@@ -243,6 +242,53 @@ public:
     if (tag == tagSingle_) return true;
     return false;
   }
+
+public:
+  // three metrics: precision, recall and F1-score
+  void getNames(std::vector<std::string>* names) {
+    this->storeLocalValues();
+    names->reserve(this->values_.size());
+    for (auto it = this->values_.begin(); it != this->values_.end(); ++it) {
+      names->push_back(this->config_.name() + "." + it->first);
+    }
+  }
+
+  // get value by field name
+  real getValue(const std::string& name, Error* err) const {
+    this->storeLocalValues();
+    std::vector<std::string> buffers;
+    paddle::str::split(name, '.', &buffers);
+    auto it = this->values_.find(buffers[buffers.size() - 1]);
+    if (it == this->values_.end()) {  // not found
+      *err = Error("No such key %s", name.c_str());
+      return 0.0f;
+    }
+
+    return it->second;
+  }
+
+  // get type of evaluator
+  std::string getType(const std::string& name, Error* err) const {
+    this->getValue(name, err);
+    if (!err->isOK()) {
+      return std::string();
+    }
+    return "chunk";
+  }
+
+private:
+  void storeLocalValues() const {
+    CHECK_GT(numOutputSegments_, 0);
+    CHECK_GT(numLabelSegments_, 0);
+    double precision = (double)numCorrect_ / numOutputSegments_;
+    double recall = (double)numCorrect_ / numLabelSegments_;
+    values_["precision"] = precision;
+    values_["recall"] = recall;
+    values_["F1-score"] =
+        !numCorrect_ ? 0 : 2 * precision * recall / (precision + recall);
+  }
+
+  mutable std::unordered_map<std::string, real> values_;
 };
 
 REGISTER_EVALUATOR(chunk, ChunkEvaluator);