余弦相似度计算C#源代码，采用经典改进tf_idf特征值-Cosine similarity calculation C# source code, using the classical features of value to improve tf_idf

介绍了TFIDF方法在文本特征提取中的应用，并阐述了其优缺点和改进方法-TFIDF method described in the text feature extraction application, and described its advantages and disadvantages and improvements

用c#方法描述了话题识别（话题跟踪与检测）的过程，主要是提取特征词、特征词词频计算、权重计算（tfidf方法），进行相似度计算，最后聚类-C# method describes the process of topic identification (topic tracking and detection), the word feature extraction, feature words word frequency calculation, weight to calculate me

tf–idf, short for term frequency–inverse document frequency, is a numerical statistic that is intended to reflect how important a word is to a document in a collection or corpus.[1]:8 It is often used as a weighting factor in information retrieval an