これは、編集距離を使用して、参照の最小編集距離部分文字列を見つけることで実行できます。ここで、同様の質問に対する私の回答 (PHP 実装) を確認してください。
文字許容誤差が間違っている最長共通部分文字列
上記のリンクの関数を使用すると、shortest_edit_substring()これを追加して、文字以外のすべて (または保持したいもの: 文字、数字など) を取り除いた後に検索を実行し、結果を元のバージョンに正しくマップすることができます。
// map a stripped down substring back to the original version
function map_substring($haystack_letters,$start,$length,$haystack, $regexp)
{
$r_haystack = str_split($haystack);
$r_haystack_letters = $r_haystack;
foreach($r_haystack as $k => $l)
{
if (preg_match($regexp,$l))
{
unset($r_haystack_letters[$k]);
}
}
$key_map = array_keys($r_haystack_letters);
$real_start = $key_map[$start];
$real_end = $key_map[$start+$length-1];
$real_length = $real_end - $real_start + 1;
return array($real_start,$real_length);
}
$haystack = 'Four score and seven years ago our fathers brought forth on this continent a new nation, conceived in liberty, and dedicated to the proposition that all men are created equal. Now we are engaged in a great civil war, testing whether that nation, or any nation, so conceived and so dedicated, can long endure. We are met on a great battle-field of that war. We have come to dedicate a portion of that field, as a final resting place for those who here gave their lives that that nation might live. It is altogether fitting and proper that we should do this. But, in a larger sense, we can not dedicate, we can not consecrate, we can not hallow this ground. The brave men, living and dead, who struggled here, have consecrated it, far above our poor power to add or detract. The world will little note, nor long remember what we say here, but it can never forget what they did here. It is for us the living, rather, to be dedicated here to the unfinished work which they who fought here have thus far so nobly advanced. It is rather for us to be here dedicated to the great task remaining before us—that from these honored dead we take increased devotion to that cause for which they gave the last full measure of devotion—that we here highly resolve that these dead shall not have died in vain—that this nation, under God, shall have a new birth of freedom—and that government of the people, by the people, for the people, shall not perish from the earth.';
$needle = 'ieldasafinalrTstingplaceforwhofoughtheregavetheirliZesthatthatn';
// strip out all non-letters
$regexp_to_strip_out = '/[^A-Za-z]/';
$haystack_letters = preg_replace($regexp_to_strip_out,'',$haystack);
list($start,$length) = shortest_edit_substring($needle,$haystack_letters);
list($real_start,$real_length) = map_substring($haystack_letters,$start,$length,$haystack,$regexp_to_strip_out);
printf("Found |%s| in |%s|, matching |%s|\n",substr($haystack,$real_start,$real_length),$haystack,$needle);
これにより、エラー修正も行われます。実際、やらないよりはやった方が簡単です。最小編集距離検索は、PHP よりも高速なものが必要な場合、他の言語で実装するのは非常に簡単です。