tweak SuggestFrequency, added example

example_test.go

@@ -35,6 +35,60 @@ func Example() {
 	// 【搜索引擎模式】： 小明 / 硕士 / 毕业 / 于 / 中国 / 科学 / 学院 / 科学院 / 中国科学院 / 计算 / 计算所 / ， / 后 / 在 / 日本 / 京都 / 大学 / 日本京都大学 / 深造 /
 }
 
+func Example_suggestFrequency() {
+	var seg jiebago.Segmenter
+	seg.LoadDictionary("dict.txt")
+
+	print := func(ch <-chan string) {
+		for word := range ch {
+			fmt.Printf(" %s /", word)
+		}
+		fmt.Println()
+	}
+	sentence := "超敏C反应蛋白是什么？"
+	fmt.Print("Before:")
+	print(seg.Cut(sentence, false))
+	word := "超敏C反应蛋白"
+	oldFrequency, _ := seg.Frequency(word)
+	frequency := seg.SuggestFrequency(word)
+	fmt.Printf("%s current frequency: %f, suggest: %f.\n", word, oldFrequency, frequency)
+	seg.AddWord(word, frequency)
+	fmt.Print("After:")
+	print(seg.Cut(sentence, false))
+
+	sentence = "如果放到post中将出错"
+	fmt.Print("Before:")
+	print(seg.Cut(sentence, false))
+	word = "中将"
+	oldFrequency, _ = seg.Frequency(word)
+	frequency = seg.SuggestFrequency("中", "将")
+	fmt.Printf("%s current frequency: %f, suggest: %f.\n", word, oldFrequency, frequency)
+	seg.AddWord(word, frequency)
+	fmt.Print("After:")
+	print(seg.Cut(sentence, false))
+
+	sentence = "今天天气不错"
+	fmt.Print("Before:")
+	print(seg.Cut(sentence, false))
+	word = "今天天气"
+	oldFrequency, _ = seg.Frequency(word)
+	frequency = seg.SuggestFrequency("今天", "天气")
+	fmt.Printf("%s current frequency: %f, suggest: %f.\n", word, oldFrequency, frequency)
+	seg.AddWord(word, frequency)
+	fmt.Print("After:")
+	print(seg.Cut(sentence, false))
+	// Output:
+	// Before: 超敏 / C / 反应 / 蛋白 / 是 / 什么 / ？ /
+	// 超敏C反应蛋白 current frequency: 0.000000, suggest: 1.000000.
+	// After: 超敏C反应蛋白 / 是 / 什么 / ？ /
+	// Before: 如果 / 放到 / post / 中将 / 出错 /
+	// 中将 current frequency: 763.000000, suggest: 494.000000.
+	// After: 如果 / 放到 / post / 中 / 将 / 出错 /
+	// Before: 今天天气 / 不错 /
+	// 今天天气 current frequency: 3.000000, suggest: 0.000000.
+	// After: 今天 / 天气 / 不错 /
+}
+
 func Example_loadUserDictionary() {
 	var seg jiebago.Segmenter
 	seg.LoadDictionary("dict.txt")

jieba.go

@@ -34,11 +34,25 @@ func (seg *Segmenter) AddWord(word string, frequency float64) {
 	seg.dict.AddToken(dictionary.NewToken(word, frequency, ""))
 }
 
-// Delete removes a word from dictionary
+// DeleteWord removes a word from dictionary
 func (seg *Segmenter) DeleteWord(word string) {
 	seg.dict.AddToken(dictionary.NewToken(word, 0.0, ""))
 }
 
+/*
+SuggestFrequency returns a suggested frequncy of a word or a long word
+cutted into several short words.
+
+This method is useful when a word in the sentence is not cutted out correctly.
+
+If a word should not be further cutted, for example word "石墨烯" should not be
+cutted into "石墨" and "烯", SuggestFrequency("石墨烯") will return the maximu
+frequency for this word.
+
+If a word should be further cutted, for example word "今天天气" should be
+further cutted into two words "今天" and "天气",  SuggestFrequency("今天", "天气")
+should return the minimum frequency for word "今天天气".
+*/
 func (seg *Segmenter) SuggestFrequency(words ...string) float64 {
 	frequency := 1.0
 	if len(words) > 1 {
@@ -48,6 +62,7 @@ func (seg *Segmenter) SuggestFrequency(words ...string) float64 {
 			}
 			frequency /= seg.dict.total
 		}
+		frequency, _ = math.Modf(frequency * seg.dict.total)
 		wordFreq := 0.0
 		if freq, ok := seg.dict.Frequency(strings.Join(words, "")); ok {
 			wordFreq = freq
@@ -63,7 +78,8 @@ func (seg *Segmenter) SuggestFrequency(words ...string) float64 {
 			}
 			frequency /= seg.dict.total
 		}
-		frequency = frequency*seg.dict.total + 1
+		frequency, _ = math.Modf(frequency * seg.dict.total)
+		frequency += 1.0
 		wordFreq := 1.0
 		if freq, ok := seg.dict.Frequency(word); ok {
 			wordFreq = freq
@@ -223,14 +239,14 @@ func (seg *Segmenter) cutDAGNoHMM(sentence string) <-chan string {
 			if reEng.MatchString(string(frag)) && len(frag) == 1 {
 				buf = append(buf, frag...)
 				x = y
-			} else {
-				if len(buf) > 0 {
-					result <- string(buf)
-					buf = make([]rune, 0)
-				}
-				result <- string(frag)
-				x = y
+				continue
 			}
+			if len(buf) > 0 {
+				result <- string(buf)
+				buf = make([]rune, 0)
+			}
+			result <- string(frag)
+			x = y
 		}
 		if len(buf) > 0 {
 			result <- string(buf)