Unify sampling backoff strategy.

1 files changed, 38 insertions, 0 deletions

diff --git a/extractor/matchings_sampler.cc b/extractor/matchings_sampler.cc
new file mode 100644
index 00000000..bb916e49
--- /dev/null
+++ b/extractor/matchings_sampler.cc
@@ -0,0 +1,38 @@
+#include "matchings_sampler.h"
+
+#include "data_array.h"
+#include "phrase_location.h"
+
+namespace extractor {
+
+MatchingsSampler::MatchingsSampler(
+    shared_ptr<DataArray> data_array, int max_samples) :
+    BackoffSampler(data_array, max_samples) {}
+
+MatchingsSampler::MatchingsSampler() {}
+
+int MatchingsSampler::GetNumSubpatterns(const PhraseLocation& location) const {
+  return location.num_subpatterns;
+}
+
+int MatchingsSampler::GetRangeLow(const PhraseLocation&) const {
+  return 0;
+}
+
+int MatchingsSampler::GetRangeHigh(const PhraseLocation& location) const {
+  return location.matchings->size() / location.num_subpatterns;
+}
+
+int MatchingsSampler::GetPosition(const PhraseLocation& location,
+                                  int index) const {
+  return (*location.matchings)[index * location.num_subpatterns];
+}
+
+void MatchingsSampler::AppendMatching(vector<int>& samples, int index,
+                                      const PhraseLocation& location) const {
+  copy(location.matchings->begin() + index,
+       location.matchings->begin() + index + location.num_subpatterns,
+       back_inserter(samples));
+}
+
+} // namespace extractor