function selectSubstringRandom($inputText, $substringLength)
{
$split = explode(" ", standardizeText($inputText));
//split standardized string into words
$pos = rand(0, strlen($inputText) - $substringLength);
//get a random position
$substring = implode(" ", array_slice($split, $pos, $substringLength));
while (inRepository($substring)) {
//while the chosen substring is found in the repository
$pos = rand(0, strlen($inputText) - $substringLength);
//get a random position
$substring = implode(" ", array_slice($split, $pos, $substringLength));
//pull out the random substring
}
return $substring;
}
function selectSubstring($useRepository, $repositoryLocations, $histogram, $inputText, $substringLength)
{
/*
* Return the lowest scored substring from $inputText
*/
$alpha = 1;
//local repository weight
$beta = 0.5;
//global repository weight
$substringScores = array();
$split = explode(" ", standardizeText($inputText));
//split standardized string into words
//iterate through all possible substrings of the specified length
for ($i = 0; $i < count($split) - $substringLength + 1; $i++) {
$substring = implode(" ", array_slice($split, $i, $substringLength));
//grab a substring of the correct length
$repositoryScore = 0;
if ($useRepository) {
//trigger on the global variable that indicates if the global repository is being used
$repositoryScore = repositoryScore($substring);
}
$score = $alpha * localScore($histogram, $substring) + $beta * $repositoryScore;
$substringScores[$i] = $score;
}
asort($substringScores);
//sort the frequency array by value but preserve keys
reset($substringScores);
//reset the key pointer so we can iterate correctly
//grab the lowest scored substring
$substring = implode(" ", array_slice($split, key($substringScores), $substringLength));
if ($useRepository) {
while (inRepository($repositoryLocations, $substring)) {
//while the chosen substring is found in the repository
if (!next($substringScores)) {
//next() returns false at the end of the array
return "";
//if a unique substring is not found, return ""
}
$substring = implode(" ", array_slice($split, key($substringScores), $substringLength));
}
}
return $substring;
}
