// Adjust the weights of all the samples to be uniform in the given charset.
// Returns the number of samples in the iterator.
int SampleIterator::UniformSamples() {
int num_good_samples = 0;
for (Begin(); !AtEnd(); Next()) {
TrainingSample* sample = MutableSample();
sample->set_weight(1.0);
++num_good_samples;
}
NormalizeSamples();
return num_good_samples;
}
// Normalize the weights of all the samples in the charset_map so they sum
// to 1. Returns the minimum assigned sample weight.
double SampleIterator::NormalizeSamples() {
double total_weight = 0.0;
int sample_count = 0;
for (Begin(); !AtEnd(); Next()) {
const TrainingSample& sample = GetSample();
total_weight += sample.weight();
++sample_count;
}
// Normalize samples.
double min_assigned_sample_weight = 1.0;
if (total_weight > 0.0) {
for (Begin(); !AtEnd(); Next()) {
TrainingSample* sample = MutableSample();
double weight = sample->weight() / total_weight;
if (weight < min_assigned_sample_weight)
min_assigned_sample_weight = weight;
sample->set_weight(weight);
}
}
return min_assigned_sample_weight;
}
