Calculate string/sentance score for score-based sorting. Use case: elasticsearch score-based search.

calculateSentanceScore.php

<?php

$alphabeth = strtolower('ABCDEFGHIJKLMNOPQRSTUVWXYZ');

$sentances = [
    'Fifa 2018',
    'Grand Theft Auto V',
    'Sims 5',
    'Hitman',
    'Assasins Creed',
    'Half-life',
    'Team Fortress 2'
];

function calculate_sentance_score($alphabeth, $sentance, $accuracy = 20) {
    $overallScore = 0;
    $weight = 0;
    $cleanedSentance = preg_replace("/[^$alphabeth]/i", '', $sentance);
    
    foreach(str_split($cleanedSentance) as $letter) {
        $letterScore = stripos($alphabeth, $letter);
        $letterScore++;
        $weight++;
        
        // exponentially lower the boost the further the letter is
        $letterBoost = 1 / pow($accuracy, $weight); 
        
        // var_dump([ $letter, $letterScore * $letterBoost ]);
        $overallScore += $letterScore * $letterBoost;
    }
    
    return $overallScore;
}

$sentanceScores = [];

foreach($sentances as $sentance) {
    $sentanceScores[$sentance] = calculate_sentance_score($alphabeth, $sentance);
}

uasort($sentanceScores, function($scoreA, $scoreB) {
    return $scoreA > $scoreB;
});

var_dump($sentanceScores);

array(10) {
  ["Assasins Creed"]=>
  float(0.09988733981233)
  ["Fifa 2018"]=>
  float(0.32325625)
  ["Grand Theft Auto V"]=>
  float(0.39521406895899)
  ["Half-life"]=>
  float(0.40404139550781)
  ["Hitman"]=>
  float(0.42508178125)
  ["Player Unknown's Battlegrounds"]=>
  float(0.83028311072606)
  ["Sims 5"]=>
  float(0.97424375)
  ["Team Fortress 2"]=>
  float(1.0127083742545)
}