private static bool MatchBloomFilter(string word, BloomFilter filter, BloomFilterParameters parameters)
{
if (parameters.Disabled)
{
return(true);
}
var processed = DataGenerator.ProcessWordForBloomFilter(parameters, word);
// Console.WriteLine("processed: " + processed);
return(filter.test(processed));
}
//private void WriteRetouched(int id, Tuple<string, int>[] retouched)
//{
// var path = Path.Combine(Settings.TempFolder, String.Format("{0:000}-retouched.txt", id));
// if (File.Exists(path)) File.Delete(path);
// File.WriteAllLines(path, retouched.Select(r => String.Format("{0} {1}", r.Item1, r.Item2)));
//}
public static string ProcessWordForBloomFilter(BloomFilterParameters parameters, string word)
{
var processed = word;
processed = SubstituteMostCommonSequences(processed, parameters.SubstitutionCount);
if (parameters.SubstringStartIndex != null)
{
processed = SampleSplitter.PreSampleForBFValue(processed);
var length = Math.Min(parameters.SubstringLength.Value, processed.Length);
processed = processed.Substring(0, length);
}
if (parameters.CharOffset != null)
{
processed = new String(processed
.Select(c => (char)(c - 'a' + parameters.CharOffset.Value))
.ToArray());
}
return(processed);
}
private void BuildBloomFilter(BloomFilterParameters parameters, GeneratedData data)
{
if (parameters.Disabled)
{
return;
}
using (new Timer("DataGenerator.BuildBloomFilter"))
{
var filter = new BloomFilter(parameters.FilterSizeBytes * 8, parameters.HashFunctionsCount);
var counter = new TestExecutor.MatchCounter();
foreach (var word in Words.Value)
{
// if (word.Length < 3) continue;
if (!TestExecutor.Match(data, word, data.Parameters, counter, skipBloomFilter: true))
{
continue;
}
var processed = ProcessWordForBloomFilter(parameters, word);
filter.add(processed);
}
data.BloomFilter = filter;
using (new Timer("DataGenerator.BuildBloomFilter[retouch]"))
{
if (parameters.RetouchWordCount > 0)
{
var retouched = FakeWordsByFrequency.Value
.Where(t => t.Item2 > 2)
.Where(t => TestExecutor.Match(data, t.Item1, data.Parameters, counter))
.Take(parameters.RetouchWordCount.Value)
.ToArray();
foreach (var tuple in retouched)
{
var word = tuple.Item1;
var processed = ProcessWordForBloomFilter(parameters, word);
filter.retouch(processed, parameters.RetouchMaxWeight ?? 0);
}
// WriteRetouched(data.Parameters.Id.Value, retouched);
}
else if (parameters.RetouchMinRelWeight != null)
{
var falsePositives = FakeWordsByFrequency.Value
.Where(t => t.Item2 > 2)
.Where(t => TestExecutor.Match(data, t.Item1, data.Parameters, counter))
.ToArray();
var falsePositivesBF = new BloomFilter(filter.m, filter.k);
foreach (var fp in falsePositives)
{
var processed = ProcessWordForBloomFilter(parameters, fp.Item1);
falsePositivesBF.add(processed, fp.Item2);
}
filter.retouch(falsePositivesBF, parameters.RetouchMinRelWeight.Value);
}
}
}
}