Function IsCurrentPredictionCorrection

examples/textcat/train_textcat.cc:150–159

};

bool IsCurrentPredictionCorrection(Expression y_pred, int y_true) {
  ComputationGraph& cg = *y_pred.pg;
  auto v = as_vector(cg.incremental_forward(y_pred));
  assert(v.size() > 1);
  int besti = 0;
  float best = v[0];
  for (unsigned i = 1; i < v.size(); ++i)
    if (v[i] > best) { best = v[i]; besti = i; }
  return (besti == y_true);
}

Expression CrossEntropyLoss(const Expression& y_pred, int y_true) {
  Expression lp = log_softmax(y_pred);