// private methods
        private static bool IsTopCandValidByScores(ContextScore orgContextScore, FrequencyScore orgFreqScore, ContextScore topContextScore, CSpellScore topCSpellScore, CSpellApi cSpellApi)
        {
            // init
            bool   flag = false;
            double rw1To1CandCsFactor = cSpellApi.GetRankRw1To1CandCsFac();
            double rw1To1WordMinCs    = cSpellApi.GetRankRw1To1WordMinCs();
            double rw1To1CandMinCs    = cSpellApi.GetRankRw1To1CandMinCs();
            double rw1To1CandCsDist   = cSpellApi.GetRankRw1To1CandCsDist();
            double rw1To1CandFsFactor = cSpellApi.GetRankRw1To1CandFsFac();
            double rw1To1CandMinFs    = cSpellApi.GetRankRw1To1CandMinFs();
            double rw1To1CandFsDist   = cSpellApi.GetRankRw1To1CandFsDist();
            double orgScore           = orgContextScore.GetScore();
            double topScore           = topContextScore.GetScore();

            // another rule for word2Vec on real-word
            // check contect score:
            // 1. the topScore is bigger enough to cover the orgScore
            // 2. the distance is > a value for confidence
            if (((topScore / -orgScore) > rw1To1CandCsFactor) && (orgScore > rw1To1WordMinCs) && (topScore > rw1To1CandMinCs) && ((topScore - orgScore) > rw1To1CandCsDist))               //609|796|0.6920
            // check frequency, all positive:
            // 1. cand has better frequency
            // 2. the difference is withint a range
            {
                double orgFScore = orgFreqScore.GetScore();
                double topFScore = topCSpellScore.GetFScore().GetScore();
                if (((topFScore / orgFScore) > rw1To1CandFsFactor) && (topFScore > rw1To1CandMinFs) && ((topFScore > orgFScore) || ((orgFScore - topFScore) < rw1To1CandFsDist)))                   // within freq range
                {
                    flag = true;
                }
            }
            return(flag);
        }
        // return the best ranked str from candidates using word2Vec score
        // inTokenList, includes space token, is not coreTerm.Lc
        // return the orignal inStr if no candidate has score > 0.0d
        public static string GetTopRankStr(string inStr, HashSet <string> candidates, CSpellApi cSpellApi, int tarPos, List <TokenObj> nonSpaceTokenList, bool debugFlag)
        {
            // init
            WordWcMap wordWcMap        = cSpellApi.GetWordWcMap();
            Word2Vec  word2VecIm       = cSpellApi.GetWord2VecIm();
            Word2Vec  word2VecOm       = cSpellApi.GetWord2VecOm();
            int       contextRadius    = cSpellApi.GetRw1To1ContextRadius();
            bool      word2VecSkipWord = cSpellApi.GetWord2VecSkipWord();
            int       maxCandNo        = cSpellApi.GetCanMaxCandNo();
            double    wf1        = cSpellApi.GetOrthoScoreEdDistFac();
            double    wf2        = cSpellApi.GetOrthoScorePhoneticFac();
            double    wf3        = cSpellApi.GetOrthoScoreOverlapFac();
            int       tarSize    = 1;    // only for one-to-one, no merge here
            string    topRankStr = inStr;
            // use cSpell top candidates
            int                topNo           = 1; // top sort
            string             inStrLc         = inStr.ToLower();
            List <CSpellScore> cSpellScoreList = RankByCSpellRealWord1To1.GetCandidateScoreList(inStrLc, candidates, wordWcMap, tarPos, tarSize, nonSpaceTokenList, word2VecIm, word2VecOm, word2VecSkipWord, contextRadius, wf1, wf2, wf3, debugFlag);

            // Find the correction str and correct
            if (cSpellScoreList.Count > 0)
            {
                // the rw top rank must be in both NC and orthographic
                CSpellScore  topScore        = cSpellScoreList[0];
                double       topFScore       = topScore.GetFScore().GetScore();         //frequency
                double       topTScore       = topScore.GetOScore().GetTokenScore();    // Token
                double       topPScore       = topScore.GetOScore().GetPhoneticScore(); //Phone
                double       topOScore       = topScore.GetOScore().GetOverlapScore();  //overlap
                ContextScore orgContextScore = null;
                // check the frequency
                // get the max score of frequency, eidt, phonetic, and overlap
                // the top rank must have all top score for above
                if ((topFScore == CSpellScore.GetMaxFScore(cSpellScoreList)) && (topTScore == CSpellScore.GetMaxEScore(cSpellScoreList)) && (topPScore == CSpellScore.GetMaxPScore(cSpellScoreList)) && (topOScore == CSpellScore.GetMaxOScore(cSpellScoreList)))
                {
                    ContextScore topContextScore = topScore.GetCScore();
                    // 1.1 wordVec for context
                    DoubleVec contextVec = Word2VecContext.GetContextVec(tarPos, tarSize, nonSpaceTokenList, word2VecIm, contextRadius, word2VecSkipWord, debugFlag);
                    // 1.2 wordVec for the original words before one-to-one
                    orgContextScore = new ContextScore(inStr, contextVec, word2VecOm);
                    FrequencyScore orgFScore = new FrequencyScore(inStr, wordWcMap);
                    // pass the orgContextScore
                    if (IsTopCandValid(inStr, orgContextScore, topScore, orgFScore, cSpellApi, debugFlag) == true)
                    {
                        // no correction: if score is not good enough for corection
                        topRankStr = topScore.GetCandStr();
                        // debug print for ananlysis
                        /// <summary>
                        ///*
                        /// System.out.println("======= cSpellScoreList.size(): "
                        ///    + cSpellScoreList.size() + " ========");
                        /// System.out.println(inStr
                        ///    + "," + String.format("%1.8f", orgFScore.GetScore())
                        ///    + "," + String.format("%1.8f", orgContextScore.GetScore()));
                        /// System.out.println(CSpellScore.GetScoreHeader());
                        /// for(CSpellScore cSpellScore: cSpellScoreList)
                        /// {
                        ///    System.out.println(cSpellScore.ToString(","));
                        /// }
                        /// **
                        /// </summary>
                    }
                }
                // debug print
                if (debugFlag == true)
                {
                    // print focus token (original)
                    if (orgContextScore != null)
                    {
                        DebugPrint.PrintScore(orgContextScore.ToString(), debugFlag);
                    }
                    else
                    {
                        DebugPrint.PrintScore("No score for focus (" + inStr + ")", debugFlag);
                    }
                    // print candidate
                    var list = cSpellScoreList.Take(maxCandNo).Select(obj => obj.ToString()).ToList();
                    foreach (var item in list)
                    {
                        DebugPrint.PrintScore(item, debugFlag);
                    }
                }
            }
            return(topRankStr);
        }