enhanced_vectorization_demo/
enhanced_vectorization_demo.rs

1//! Enhanced text vectorization demonstration
2//!
3//! This example shows how to use the enhanced vectorizers with n-gram support,
4//! document frequency filtering, and advanced TF-IDF options.
5
6use scirs2_text::{
7    enhanced_vectorize::{EnhancedCountVectorizer, EnhancedTfidfVectorizer},
8    preprocess::BasicTextCleaner,
9    preprocess::TextCleaner,
10};
11
12#[allow(dead_code)]
13fn main() -> Result<(), Box<dyn std::error::Error>> {
14    println!("=== Enhanced Text Vectorization Demo ===\n");
15
16    let documents = vec![
17        "The quick brown fox jumps over the lazy dog.",
18        "A fast red fox leaped over the sleeping canine.",
19        "Machine learning algorithms process textual data efficiently.",
20        "Text processing and natural language understanding are important.",
21        "Natural language processing is a field of artificial intelligence.",
22        "Deep learning models can understand complex text patterns.",
23    ];
24
25    // 1. Enhanced Count Vectorizer with Unigrams
26    println!("1. Enhanced Count Vectorizer (Unigrams only)");
27    let mut count_vec_unigram = EnhancedCountVectorizer::new()
28        .set_binary(false)
29        .set_max_features(Some(20));
30
31    count_vec_unigram.fit(&documents)?;
32    let count_matrix = count_vec_unigram.transform_batch(&documents)?;
33
34    println!("Vocabulary size: {}", count_vec_unigram.vocabulary().len());
35    println!("Count matrix shape: {:?}", count_matrix.shape());
36    println!();
37
38    // 2. Enhanced Count Vectorizer with N-grams
39    println!("2. Enhanced Count Vectorizer (Unigrams + Bigrams)");
40    let mut count_vec_ngram = EnhancedCountVectorizer::new()
41        .set_ngram_range((1, 2))?
42        .set_max_features(Some(30));
43
44    count_vec_ngram.fit(&documents)?;
45    let ngram_matrix = count_vec_ngram.transform_batch(&documents)?;
46
47    println!(
48        "Vocabulary size with n-grams: {}",
49        count_vec_ngram.vocabulary().len()
50    );
51    println!("N-gram count matrix shape: {:?}", ngram_matrix.shape());
52
53    // Show some n-gram tokens
54    let vocab = count_vec_ngram.vocabulary();
55    let mut ngram_tokens: Vec<String> = Vec::new();
56    for i in 0..vocab.len().min(10) {
57        if let Some(token) = vocab.get_token(i) {
58            if token.contains(' ') {
59                // This is a bigram
60                ngram_tokens.push(token.to_string());
61            }
62        }
63    }
64    println!("Sample bigrams: {ngram_tokens:?}");
65    println!();
66
67    // 3. Enhanced Count Vectorizer with Document Frequency Filtering
68    println!("3. Count Vectorizer with Document Frequency Filtering");
69    let mut count_vec_filtered = EnhancedCountVectorizer::new()
70        .set_min_df(0.3)?  // Token must appear in at least 30% of documents
71        .set_max_df(0.8)?; // Token must appear in at most 80% of documents
72
73    count_vec_filtered.fit(&documents)?;
74
75    println!(
76        "Vocabulary size after DF filtering: {}",
77        count_vec_filtered.vocabulary().len()
78    );
79    println!();
80
81    // 4. Enhanced TF-IDF Vectorizer with N-grams
82    println!("4. Enhanced TF-IDF Vectorizer with N-grams");
83    let mut tfidf_vec = EnhancedTfidfVectorizer::new()
84        .set_ngram_range((1, 2))?
85        .set_max_features(Some(50))
86        .set_smooth_idf(true)
87        .set_sublinear_tf(true)
88        .set_norm(Some("l2".to_string()))?;
89
90    tfidf_vec.fit(&documents)?;
91    let tfidf_matrix = tfidf_vec.transform_batch(&documents)?;
92
93    println!("TF-IDF matrix shape: {:?}", tfidf_matrix.shape());
94    println!("TF-IDF with smoothing and sublinear TF applied");
95
96    // Show TF-IDF values for first document
97    let first_doc_tfidf = tfidf_matrix.row(0);
98    let mut top_features: Vec<(String, f64)> = Vec::new();
99
100    for (idx, &value) in first_doc_tfidf.iter().enumerate() {
101        if value > 0.0 {
102            if let Some(token) = tfidf_vec.vocabulary().get_token(idx) {
103                top_features.push((token.to_string(), value));
104            }
105        }
106    }
107
108    top_features.sort_by(|a, b| b.1.partial_cmp(&a.1).unwrap());
109    println!("\nTop TF-IDF features for first document:");
110    for (token, score) in top_features.iter().take(5) {
111        println!("  {token}: {score:.3}");
112    }
113    println!();
114
115    // 5. Processing with Text Cleaning
116    println!("5. Vectorization with Text Preprocessing");
117    let cleaner = BasicTextCleaner::new(true, true, true);
118
119    // Clean documents first
120    let cleaned_docs: Result<Vec<_>, _> = documents.iter().map(|doc| cleaner.clean(doc)).collect();
121    let cleaned_docs = cleaned_docs?;
122    let cleaned_refs: Vec<&str> = cleaned_docs.iter().map(|s| s.as_str()).collect();
123
124    let mut tfidf_cleaned = EnhancedTfidfVectorizer::new()
125        .set_ngram_range((1, 2))?
126        .set_max_features(Some(30));
127
128    tfidf_cleaned.fit(&cleaned_refs)?;
129    let cleaned_matrix = tfidf_cleaned.transform_batch(&cleaned_refs)?;
130
131    println!("TF-IDF shape after cleaning: {:?}", cleaned_matrix.shape());
132    println!("Processing pipeline: Clean -> Tokenize -> Vectorize");
133
134    Ok(())
135}