simterms.inc.php

<?php

/**************************************************************
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For more information, please refer to [http://unlicense.org/].
***************************************************************/

/**************************************************************
PHP Utility Functions to calculate similar terms of a term
***************************************************************/

// -------------------------------------------------------------

function letterPairs($str) {
	$numPairs = mb_strlen($str) - 1;
	$pairs = array();
	for ($i = 0; $i < $numPairs; $i ++) {
		$pairs[$i] = mb_substr($str, $i, 2);
	}
	return $pairs;
}

function wordLetterPairs($str) {
	$allPairs = array();
	$words = explode(' ', $str);
	for ($w = 0; $w < count($words); $w ++) {
		$pairsInWord = letterPairs($words[$w]);
		for ($p = 0; $p < count($pairsInWord); $p ++) {
			$allPairs[$pairsInWord[$p]] = $pairsInWord[$p];
		}
	}
	return array_values($allPairs);
}

function getSimilarityRanking($str1, $str2) {
	// Returns SimilarityRanking of two UTF-8 strings $str1 and $str2
	// Source http://www.catalysoft.com/articles/StrikeAMatch.html
	// Source http://stackoverflow.com/questions/653157
	$pairs1 = wordLetterPairs($str1);
	$pairs2 = wordLetterPairs($str2);
	$union = count($pairs1) + count($pairs2);
	if ($union == 0) return 0;
	$intersection = count(array_intersect($pairs1, $pairs2));
	return (2.0 * $intersection) / $union;
}

// -------------------------------------------------------------

function get_similar_terms($lang_id, $compared_term, $max_count, 
	$min_ranking) {
	// For a language $lang_id and a term $compared_term (UTF-8), 
	// return an array with $max_count wordids with a similarity ranking 
	// > $min_ranking, sorted decending. 
	// If string is already in database, it will be excluded in results.
	global $tbpref;
	$compared_term_lc = mb_strtolower($compared_term, 'UTF-8');
	$sql = "select WoID, WoTextLC from " . $tbpref . "words where WoLgID = " . $lang_id . " AND WoTextLC <> " . convert_string_to_sqlsyntax($compared_term_lc);
	$res = do_mysql_query($sql);
	$termlsd = array();
	while ($record = mysql_fetch_assoc($res)) {
		$termlsd[$record["WoID"]] = getSimilarityRanking($compared_term_lc, $record["WoTextLC"]);
	}
	mysql_free_result($res);
	arsort($termlsd, SORT_NUMERIC);
	$r = array();
	$i = 0;
	foreach ($termlsd as $key => $val) {
		if ($i >= $max_count) break;
		if ($val < $min_ranking) break;
  	$i++;
  	$r[$i] = $key;
	}
	return $r;
}

// -------------------------------------------------------------

function print_similar_terms($lang_id, $compared_term) {
	// Get Term and translation of terms in termid array (calculated 
	// in function get_similar_terms(...)) as string for echo
	global $tbpref;
	$max_count = (int)getSettingWithDefault("set-similar-terms-count");
	if ($max_count <= 0) return '';
	if (trim($compared_term) == '') return '&nbsp;'; 
	$compare = tohtml($compared_term);
	$termarr = get_similar_terms($lang_id, $compared_term, $max_count, 0.33);
	$rarr = array();
	foreach ($termarr as $termid) {
		$sql = "select WoText, WoTranslation, WoRomanization from " . $tbpref . "words where WoID = " . $termid;
		$res = do_mysql_query($sql);
		if ($record = mysql_fetch_assoc($res)) {
			$term = tohtml($record["WoText"]);
			if (stripos($compare, $term) !== FALSE)
				$term = '<span class="red3">' . $term . '</span>';
			else
				$term = str_replace($compare, '<span class="red3"><u>' . $compare . '</u></span>', $term);
			$tra = $record["WoTranslation"];
			if ($tra == "*") $tra = "???";
			if (trim($record["WoRomanization"]) !== '') {
				$romd = " [" . $record["WoRomanization"] . "]";
				$rom = $record["WoRomanization"];
			}
			else {
    		$romd = "";
    		$rom = "";
    	}
    	$rarr[] = '<img class="clickedit" src="icn/tick-button-small.png" title="Copy → Translation &amp; Romanization Field(s)" onclick="setTransRoman(' . prepare_textdata_js($tra) . ',' . prepare_textdata_js($rom) . ');" /> ' . $term . tohtml($romd) . ' — ' . tohtml($tra) . '<br />';
		}
		mysql_free_result($res);
	}
	if(count($rarr) == 0)
		return "(none)";
	else
		return implode($rarr);
}

// -------------------------------------------------------------

function print_similar_terms_tabrow() {
	if ((int)getSettingWithDefault("set-similar-terms-count") > 0) 
		echo '<tr><td class="td1 right">Similar<br />Terms:</td><td class="td1"><span id="simwords" class="smaller">&nbsp;</span></td></tr>';
} 

// -------------------------------------------------------------

?>