added utils folder; added several suplamentary modules

1 files changed, 0 insertions, 92 deletions

diff --git a/pieces/match-util.js b/pieces/match-util.js
deleted file mode 100644
index a13fddb..0000000
--- a/pieces/match-util.js
+++ /dev/null
@@ -1,92 +0,0 @@
-/** Ngram fuzzy match algorithm
- * (simple and fast)
- */
-const createNgram = (word, n) => {          // Ngram creation
-    if (word.length <3)     return word;
-    const vector = [];
-    for (let i = 0; i < word.length-n+1; ++i) {
-        vector.push(word.slice(i, i + n));
-    }
-    return vector;
-};
-
-/** similarity
- * rates similarity between 2 words
- * based on Ngram matches of N = n letters;
- * implements a 2-dim check (all a-Ngrams vs all all b-Ngrams)
- * 
- * @param {string} a : first word
- * @param {string} b : second word
- * @param {int} n : Ngram base
- * @returns {float} : match percentage as a float in [0, 1]
- */
-const similarity = (a, b, n) => {         // Ngram match score
-    if (a.length > 0 && b.length > 0) {
-        const aNgram = createNgram(a, n);
-        const bNgram = createNgram(b, n);
-        let hits = 0;
-        for (let x = 0; x < aNgram.length; ++x) {
-            for (let y = 0; y < bNgram.length; ++y) {
-                if (aNgram[x] === bNgram[y]) {
-                    hits += 1;
-                }
-            }
-        }
-        if (hits > 0) {
-            const union = aNgram.length + bNgram.length;
-            return (2.0 * hits) / union;
-        }
-    }
-    return 0;
-};
-
-/** resemblance
- * is an alternative similarity rating;
- * implements an 1-dim Ngram similarity check
- * and it's much faster than similarity()
- */
-const resemblance = (a, b, n) => {
-    if (a.length > n && b.length >= a.length) {
-        const aNgram = createNgram(a, n);
-        let hits = 0;
-        for (let i = 0; i < aNgram.length; ++i) {
-            if (b.includes(aNgram[i])) {
-                hits++;
-            }
-        }
-        if (hits > 0) {
-            // rate resemblance based on hits and length-similarity
-            return (hits / aNgram.length) * (a.length / b.length);
-        }
-    }
-    return 0;
-}
-
-
-/** is_exact_match
- * 
- * check if a searching string -> query (string/latin in kb-format)
- * matches exactly an item of the array of synonyms -> chkArr (array of utf-8/strings)
- * 
- * @param query (string): searching string; string/latin in kb-format
- * @param chkArr (array): array of synonyms; (array of utf-8/strings)
- * @return (boolean): true|false
- */
-function exact( query, chkArr ) {
-    found = false;
-    chkArr.forEach( w => { if (w == query) found = true });
-    return found;
-}
-
-function partial( query, chkArr ) {
-    found = false;
-    chkArr.forEach( w => { if (w.includes(query)) found = true });
-    return found;
-}
-
-module.exports = {
-    exact,
-    partial,
-    similarity,
-    resemblance
-}