protected override IList <TranslationMemory.SearchResults> SearchMultipleSegmentsInternal(TranslationMemory.SearchSettings settings, IList <Core.Segment> searchSegments)
{
lock (_serviceLockObject)
{
List <Core.Segment> translatedSegments = null;
translatedSegments = new List <Core.Segment>();
foreach (Core.Segment segment in searchSegments)
{
Core.Segment translation = _service.Translate(segment);
// If We Got Nothing Back, Create A Blank Segment To Prevent Errors Further Along
if (translation == null)
{
translation = new Core.Segment(this.LanguageDirection.TargetCulture);
}
translatedSegments.Add(translation);
}
if (translatedSegments.Count != searchSegments.Count)
{
throw new Exception(PluginResources.EMSG_InvalidTranslationCount);
}
return(CreateSearchResultsFromTranslations(searchSegments, translatedSegments));
}
}
/// <summary>
/// Attempts to identify the locations of (substrings of) the search segment in the result segment.
/// Typically, the search segment is a single search string (such as a concordance search string),
/// and the result segment is a transation unit segment.
/// </summary>
/// <param name="searchSegment">The search segment or search word. The segment must be tokenized.</param>
/// <param name="textSegment">The text segment, usually a sentence or larger block of text.
/// The segment must be tokenized.</param>
/// <returns>The locations and other information about the coverage of the search segment
/// in the result segment.</returns>
public static TermFinderResult FindTerms(Core.Segment searchSegment,
Core.Segment textSegment,
bool expectContinuousMatch)
{
/*
* Scoring parameters:
*
* - coverage of query string - the more the better
* - coverage of query string by the largest fragment?
* - number of fragments - the fewer the better
* - distance of fragments - the smaller the better
* - avg size of fragments? variance? - few large better than many small, even with larger distance
* - coverage of fragment relative to the token(s) it spans
* - consistent word order, inserted words
*
* Delete very small fragments (maybe not in FE languages?)
* Number of tokens in query?
* */
if (searchSegment == null)
{
throw new ArgumentNullException("searchSegment");
}
if (textSegment == null)
{
throw new ArgumentNullException("textSegment");
}
if (searchSegment.Tokens == null || textSegment.Tokens == null)
{
throw new ArgumentException("Segments are expected to be tokenized");
}
if (searchSegment.Culture == null || textSegment.Culture == null)
{
throw new ArgumentException("At least one segment culture is null");
}
if (!Core.CultureInfoExtensions.AreCompatible(searchSegment.Culture, textSegment.Culture))
{
throw new ArgumentException("Segment cultures are incompatible");
}
if (searchSegment.Tokens.Count == 0 || textSegment.Tokens.Count == 0)
{
return(null);
}
bool usesBlanksAsSeparators = Core.CultureInfoExtensions.UseBlankAsWordSeparator(searchSegment.Culture);
if (usesBlanksAsSeparators)
{
return(FindTermsWordBased(searchSegment, textSegment, expectContinuousMatch));
}
else
{
return(FindTermsCharBased(searchSegment, textSegment, expectContinuousMatch));
}
}
public List <Core.Tokenization.Token> Tokenize(Core.Segment s, bool allowTokenBundles)
{
// TODO check whether segment culture is compatible with tokenizer parameter's culture? Or accept junk-in-junk-out?
List <Token> result = new List <Token>();
int run = -1;
foreach (SegmentElement se in s.Elements)
{
++run;
if (se == null)
{
System.Diagnostics.Debug.Assert(false, "empty segment run!");
continue;
}
Text txtR = se as Text;
Token tokR = se as Token;
Tag tagR = se as Tag;
if (tagR != null)
{
// TODO rather have a "markup token" type?
Token t = new TagToken(tagR);
t.Span = new SegmentRange(run, 0, 0);
result.Add(t);
}
else if (tokR != null)
{
// partially pretokenized input
// TODO duplicate token/deep copy?
tokR.Span = new SegmentRange(run, 0, 0);
result.Add(tokR);
}
else if (txtR != null)
{
List <Token> tokenized = TokenizeInternal(txtR.Value, run, _Parameters.CreateWhitespaceTokens, allowTokenBundles);
if (tokenized != null && tokenized.Count > 0)
{
result.AddRange(tokenized);
}
}
else
{
System.Diagnostics.Debug.Assert(false, "Unknown segment run type");
}
}
ReclassifyAcronyms(result);
return(result);
}
protected override TranslationMemory.SearchResults SearchSingleSegmentInternal(TranslationMemory.SearchSettings settings, Core.Segment segment)
{
if (segment == null)
{
return(null);
}
lock (_serviceLockObject)
{
Core.Segment translation = _service.Translate(segment);
return(CreateSearchResultFromTranslation(segment, translation));
}
}
/// <summary>
/// Verifies that all ranges are "inside" the segment's (text) elements.
/// </summary>
private static bool VerifyRanges(IEnumerable <Core.SegmentRange> ranges,
Core.Segment segment)
{
if (ranges == null)
{
return(true);
}
foreach (Core.SegmentRange sr in ranges)
{
if (sr == null || sr.From == null || sr.Into == null)
{
return(false);
}
if (sr.From.Index != sr.Into.Index)
{
return(false);
}
if (sr.From.Index < 0 || sr.From.Index >= segment.Elements.Count)
{
return(false);
}
if (sr.From.Position > sr.Into.Position)
{
return(false);
}
Core.Text txt = segment.Elements[sr.From.Index] as Core.Text;
if (txt == null)
{
return(false);
}
if (sr.From.Position >= txt.Value.Length || sr.Into.Position >= txt.Value.Length)
{
return(false);
}
}
return(true);
}
private static int[,] ComputeTokenAssociationScores(Core.Segment searchSegment, Core.Segment textSegment)
{
int[,] overlaps = new int[searchSegment.Tokens.Count, textSegment.Tokens.Count];
CaseAwareCharSubsequenceScoreProvider scorer = new CaseAwareCharSubsequenceScoreProvider();
Core.Tokenization.Token srcToken;
Core.Tokenization.Token txtToken;
for (int s = 0; s < searchSegment.Tokens.Count; ++s)
{
srcToken = searchSegment.Tokens[s];
if (srcToken.IsWhitespace || srcToken is Core.Tokenization.TagToken)
{
continue;
}
for (int t = 0; t < textSegment.Tokens.Count; ++t)
{
txtToken = textSegment.Tokens[t];
if (txtToken.IsWhitespace || txtToken is Core.Tokenization.TagToken)
{
continue;
}
overlaps[s, t] = 0;
// TODO relax equality criteria on placeables of the same type
// TODO does the score include information whether tolower/tobase has
// been applied?
List <AlignedSubstring> alignment
= SequenceAlignmentComputer <char> .ComputeLongestCommonSubsequence(srcToken.Text.ToCharArray(),
txtToken.Text.ToCharArray(), 0, scorer, null);
if (alignment == null || alignment.Count == 0)
{
continue;
}
int common = alignment.Sum(x => x.Length);
if (common == 0)
{
continue;
}
// dice
// TODO experiment with other scoring methods? Scoring only relative to query?
float score = 2.0f * common / (float)(srcToken.Text.Length + txtToken.Text.Length);
if (score >= _DICE_THRESHOLD)
{
// percentage of score
overlaps[s, t] = (int)(score * 100.0f);
System.Diagnostics.Debug.Assert(overlaps[s, t] >= 0 && overlaps[s, t] <= 100);
}
}
}
return(overlaps);
}
private static TermFinderResult FindTermsWordBased(Core.Segment searchSegment,
Core.Segment textSegment, bool expectContinuousMatch)
{
// compute the maximum overlap scores for each token in the source and each token in the text,
// using LCS or ED
const bool useLcsScoreAdjustment = true;
int[,] overlaps = ComputeTokenAssociationScores(searchSegment, textSegment);
int[] maxScores = new int[searchSegment.Tokens.Count];
TermFinderResult result = new TermFinderResult();
result.MatchingRanges = new List <Sdl.LanguagePlatform.Core.SegmentRange>();
System.Collections.BitArray coveredTargetTokens
= new System.Collections.BitArray(textSegment.Tokens.Count);
IList <string> srcConcatenatedTokens = new List <string>();
IList <string> trgConcatenatedTokens = new List <string>();
int nonwhiteSearchTokens = 0;
for (int s = 0; s < searchSegment.Tokens.Count; ++s)
{
if (!searchSegment.Tokens[s].IsWhitespace)
{
++nonwhiteSearchTokens;
if (useLcsScoreAdjustment)
{
srcConcatenatedTokens.Add(searchSegment.Tokens[s].Text.ToLowerInvariant());
}
}
for (int t = 0; t < textSegment.Tokens.Count; ++t)
{
if (overlaps[s, t] > 0)
{
if (!coveredTargetTokens[t])
{
result.MatchingRanges.Add(textSegment.Tokens[t].Span);
coveredTargetTokens[t] = true;
}
if (overlaps[s, t] > maxScores[s])
{
System.Diagnostics.Debug.Assert(overlaps[s, t] >= 0 && overlaps[s, t] <= 100);
maxScores[s] = overlaps[s, t];
}
}
}
}
if (nonwhiteSearchTokens == 0)
{
return(null);
}
int tokenOverlapScore = (int)((float)maxScores.Sum() / (float)nonwhiteSearchTokens);
if (useLcsScoreAdjustment)
{
int relevantTextTokens = 0;
// TODO this won't work really well if the same search token appears
// multiple times int the match - the concatenation will include all
// occurrences (which will reduce the LCS score) and also increase the
// text token count (further reducing the LCS score)
for (int tokenIndex = 0; tokenIndex < textSegment.Tokens.Count; ++tokenIndex)
{
if (coveredTargetTokens[tokenIndex])
{
if (trgConcatenatedTokens.Count > 0)
{
int previousWordTokenIndex = GetPreviousWordTokenIndex(textSegment.Tokens, tokenIndex);
if ((previousWordTokenIndex > -1) && (!coveredTargetTokens[previousWordTokenIndex]))
{
const string UnmatchedToken = "#";
trgConcatenatedTokens.Add(UnmatchedToken);
}
}
++relevantTextTokens;
trgConcatenatedTokens.Add(textSegment.Tokens[tokenIndex].Text.ToLowerInvariant());
}
}
string srcConcat = string.Join("~", srcConcatenatedTokens.ToArray());
string trgConcat = string.Join("~", trgConcatenatedTokens.ToArray());
int lcsOverlapScore = 0;
if ((expectContinuousMatch || tokenOverlapScore < 100) &&
srcConcat.Length > 0 && trgConcat.Length > 0)
{
List <AlignedSubstring> lcs = SequenceAlignmentComputer <char> .ComputeLongestCommonSubsequence(srcConcat.ToCharArray(),
trgConcat.ToCharArray(), 1,
new SimpleCharLSAScoreProvider(), null);
int lcsOverlap = lcs.Sum(x => x.Length);
// dice again, this time on the concatenated strings of the tokens, with a
// penalty if the number of tokens differs [0..1]
float tokenCountDeltaPenalty = 2.0f * (float)Math.Min(nonwhiteSearchTokens, relevantTextTokens)
/ (float)(nonwhiteSearchTokens + relevantTextTokens);
// another dice
// 2009-08-10, OC: reduce token count delta penalty
lcsOverlapScore = (int)(((75.0f + 25.0f * tokenCountDeltaPenalty)
* 2.0f * (float)lcsOverlap) / (float)(srcConcat.Length + trgConcat.Length));
if (lcsOverlapScore < 0)
{
lcsOverlapScore = 0;
}
if (lcsOverlapScore > 100)
{
lcsOverlapScore = 100;
}
System.Diagnostics.Debug.Assert(lcsOverlapScore >= 0 && lcsOverlapScore <= 100);
}
if (tokenOverlapScore == 100 && lcsOverlapScore > 0)
{
// discontinuous/swapped match - not sure how to penalize
// TODO work out exact scoring
result.Score = (200 + lcsOverlapScore) / 3;
}
else
{
result.Score = Math.Max(tokenOverlapScore, lcsOverlapScore);
}
}
else
{
result.Score = tokenOverlapScore;
}
return(result);
}
private static TermFinderResult FindTermsCharBased(Core.Segment searchSegment,
Core.Segment textSegment, bool expectContinuousMatch)
{
// This should only be used for far-east languages
// these ranges capture the mapping from a character position in the plain text arrays
// to a segment position (run/position pairs)
List <Core.SegmentPosition> searchSegmentPositions;
List <Core.SegmentPosition> textSegmentPositions;
string searchPlain = searchSegment.ToPlain(true, true, out searchSegmentPositions);
string textPlain = textSegment.ToPlain(true, true, out textSegmentPositions);
if (searchPlain.Length == 0)
{
// TODO may need to look into what may cause such an issue:
System.Diagnostics.Debug.Assert(false, "Let Oli know and provide test data");
return(null);
}
char[] searchPlainArray = searchPlain.ToCharArray();
char[] textPlainArray = textPlain.ToCharArray();
int searchPlainLength = searchPlain.Length;
int textPlainLength = textPlain.Length;
System.Diagnostics.Debug.Assert(searchPlainLength == searchPlainArray.Length);
System.Diagnostics.Debug.Assert(textPlainLength == textPlainArray.Length);
List <AlignedSubstring> lcs = null;
SubstringAlignmentDisambiguator picker
= new SubstringAlignmentDisambiguator();
lcs = SequenceAlignmentComputer <char> .ComputeCoverage(searchPlainArray,
textPlainArray, new CharSubstringScoreProvider(), picker);
if (lcs == null || lcs.Count == 0)
{
return(null);
}
TermFinderResult result = new TermFinderResult();
result.MatchingRanges = new List <Sdl.LanguagePlatform.Core.SegmentRange>();
List <Core.SegmentPosition> textPositions = new List <Core.SegmentPosition>();
for (int subIdx = 0; subIdx < lcs.Count; ++subIdx)
{
AlignedSubstring sub = lcs[subIdx];
if (sub.Source.Length != sub.Target.Length)
{
// NOTE LCSubseq instead of Substring? Check scorer if this fires
System.Diagnostics.Debug.Assert(false, "Not supported - let Oli know and provide test data");
return(null);
}
for (int p = 0; p < sub.Source.Length; ++p)
{
textPositions.Add(textSegmentPositions[sub.Target.Start + p]);
}
}
if (textPositions.Count == 0)
{
return(null);
}
// covered ranges in the text segment:
result.MatchingRanges = SortAndMelt(textPositions);
// TODO this does not capture adjacency
float baseScore = (float)textPositions.Count / (float)searchPlainLength;
#if DEBUG
bool ok = VerifyRanges(result.MatchingRanges,
textSegment);
if (!ok)
{
System.Diagnostics.Debug.Assert(false, "Range verification failed");
}
#endif
result.Score = (int)(100.0f * baseScore);
if (result.Score < 0)
{
result.Score = 0;
}
else if (result.Score > 100)
{
result.Score = 100;
}
return(result);
}
public List <Core.Tokenization.Token> Tokenize(Core.Segment s)
{
return(Tokenize(s, false));
}