I built a simple PHP spellchecker and suggestions app that uses PHP's similar_text() and levenshtein() functions to compare words from a dictionary that is loaded into an array.
- How it works is first I load the contents of the dictionary into an array.
- I split the user's input into words and spell check each of the words.
- I spell check by checking if the word is in the array that is the dictionary.
- If it is, then I echo a congratulations message and move on.
- If not, I iterate through the dictionary-array comparing each word, in the dictionary-array, with the assumed misspelling.
- If the inputted word, in lower-case and without punctuation, is 90% or more similar to a word in the dictionary array, then I copy that word from the dictionary array into an array of suggestions.
- If no suggestions were found using the 90% or higher similarity comparison, then I use levenshtein() to do a more liberal comparison and add suggestions to the suggestions array.
- Then I iterate through the suggestions array and echo each suggestion.
I noticed that this is running slowly. Slow enough to notice. And I was wondering how I could improve the speed and efficiency of this spell checker.
Any and all changes, improvements, suggestions, and code are welcome and appreciated.
Here is the code (For syntax highlighted code, please visit here):
<?php
function addTo($line){
return strtolower(trim($line));
}
$words = array_map('addTo', file('dictionary.txt'));
$words = array_unique($words);
function checkSpelling($input, $words){
$suggestions = array();
if(in_array($input, $words)){
echo "you spelled the word right!";
}
else{
foreach($words as $word){
$percentageSimilarity=0.0;
$input = preg_replace('/[^a-z0-9 ]+/i', '', $input);
similar_text(strtolower(trim($input)), strtolower(trim($word)), $percentageSimilarity);
if($percentageSimilarity>=90 && $percentageSimilarity<100){
if(!in_array($suggestions)){
array_push($suggestions, $word);
}
}
}
if(empty($suggestions)){
foreach($words as $word){
$input = preg_replace('/[^a-z0-9 ]+/i', '', $input);
$levenshtein = levenshtein(strtolower(trim($input)), strtolower(trim($word)));
if($levenshtein<=2 && $levenshtein>0){
if(!in_array($suggestions)){
array_push($suggestions, $word);
}
}
}
}
echo "Looks like you spelled that wrong. Here are some suggestions: <br />";
foreach($suggestions as $suggestion){
echo "<br />".$suggestion."<br />";
}
}
}
if(isset($_GET['check'])){
$input = trim($_GET['check']);
$sentence='';
if(stripos($input, ' ')!==false){
$sentence = explode(' ', $input);
foreach($sentence as $item){
checkSpelling($item, $words);
}
}
else{
checkSpelling($input, $words);
}
}
?>
<!Doctype HTMl>
<html lang="en">
<head>
<meta charset="utf-8" />
<title>Spell Check</title>
</head>
<body>
<form method="get">
<input type="text" name="check" autocomplete="off" autofocus />
</form>
</body>
</html>
