Esempio n. 1
0
            /// <summary>
            /// Calculates the Dice Coefficient for two given strings.
            /// </summary>
            /// <remarks>This is a similarity metric based on bigrams that is calculated as follows:
            /// * D is Dice coefficient
            /// * SB is Shared Bigrams
            /// * TBg1 is total number of bigrams in Qgram1
            /// * TBg2 is total number of bigrams in Qgram2
            /// * D = (2SB)/(TBg1+TBg2)
            /// A good Dice Coefficient value would be a value greater than 0.33</remarks>
            /// <param name="pStr1">First string to compare</param>
            /// <param name="pStr2">Second string to compare</param>
            /// <returns>Dice Coefficient</returns>
            internal static double DiceCoefficient(String pStr1, String pStr2)
            {
                // faulty input parameters
                if (string.IsNullOrEmpty(pStr1) || string.IsNullOrEmpty(pStr1))
                {
                    return(0.0);
                }

                var bigram1 = Bigram.Parse(pStr1);
                var bigram2 = Bigram.Parse(pStr2);

                // calculate number of shared bigrams
                int sharedBigrams = 0;

                foreach (var s1 in bigram1)
                {
                    foreach (var s2 in bigram2)
                    {
                        if (s1.Equals(s2))
                        {
                            sharedBigrams++;
                        }
                    }
                }

                // calculate dice coefficient
                double dice = Convert.ToDouble(sharedBigrams * 2) / Convert.ToDouble(bigram1.Length + bigram2.Length);

                return(dice);
            }
Esempio n. 2
0
            /// <summary>
            /// Calculates the Dice Coefficient for two given strings.
            /// </summary>
            /// <remarks>This is a similarity metric based on bigrams that is calculated as follows:
            /// * D is Dice coefficient
            /// * SB is Shared Bigrams
            /// * TBg1 is total number of bigrams in Qgram1
            /// * TBg2 is total number of bigrams in Qgram2
            /// * D = (2SB)/(TBg1+TBg2)
            /// A good Dice Coefficient value would be a value greater than 0.33</remarks>
            /// <param name="pStr1">First string to compare</param>
            /// <param name="pStr2">Second string to compare</param>
            /// <returns>Dice Coefficient</returns>
            internal static double DiceCoefficient(string pStr1, string pStr2)
            {
                // faulty input parameters
                if (string.IsNullOrEmpty(pStr1) || string.IsNullOrEmpty(pStr1))
                {
                    return(0.0);
                }

                var bigram1 = Bigram.Parse(pStr1);
                var bigram2 = Bigram.Parse(pStr2);

                // calculate number of shared bigrams
                var sharedBigrams = bigram1.Sum(s1 => bigram2.Count(s1.Equals));

                // calculate dice coefficient
                return(Convert.ToDouble(sharedBigrams * 2) / Convert.ToDouble(bigram1.Length + bigram2.Length));
            }