我目前正在为用户提供在过滤 ngram 频率的文本正文时是否包含停用词的选项。通常,这样做如下:
snowballAnalyzer = new SnowballAnalyzer(Version.LUCENE_30, "English", stopWords);
shingleAnalyzer = new ShingleAnalyzerWrapper(snowballAnalyzer, this.getnGramLength());
stopWords 设置为要包含在 ngram 中或从中删除的完整单词列表。this.getnGramLength()); 仅包含当前 ngram 长度,最多为三个。
如果我在为 trigrams 过滤文本“卫星肯定掉到地球”中使用停用词,则输出为:
No=1, Key=to, Freq=1
No=2, Key=definitely, Freq=1
No=3, Key=falling to earth, Freq=1
No=4, Key=satellite, Freq=1
No=5, Key=is, Freq=1
No=6, Key=definitely falling to, Freq=1
No=7, Key=definitely falling, Freq=1
No=8, Key=falling, Freq=1
No=9, Key=to earth, Freq=1
No=10, Key=satellite is, Freq=1
No=11, Key=is definitely, Freq=1
No=12, Key=falling to, Freq=1
No=13, Key=is definitely falling, Freq=1
No=14, Key=earth, Freq=1
No=15, Key=satellite is definitely, Freq=1
但是,如果我不对三元组使用停用词,则输出是这样的:
No=1, Key=satellite, Freq=1
No=2, Key=falling _, Freq=1
No=3, Key=satellite _ _, Freq=1
No=4, Key=_ earth, Freq=1
No=5, Key=falling, Freq=1
No=6, Key=satellite _, Freq=1
No=7, Key=_ _, Freq=1
No=8, Key=_ falling _, Freq=1
No=9, Key=falling _ earth, Freq=1
No=10, Key=_, Freq=3
No=11, Key=earth, Freq=1
No=12, Key=_ _ falling, Freq=1
No=13, Key=_ falling, Freq=1
为什么我看到下划线?我会想到看到简单的一元组,“卫星坠落”,“坠落地球”和“卫星坠落地球”?绝对在我使用的停用词集中。
我可以用下划线过滤掉结果,但是......