最初の文字に応じて単語を分割する

Question

私は、最初の文字に応じて各単語をグループ化し、グループを他の文字でソートしたいという段落があります。

サンプルテキスト：最後は、市民頼むかもしれないのはなぜ最初sentence-

ため

$text = "Why end might ask civil again spoil. She dinner she our horses depend. Remember at children by reserved to vicinity. In affronting unreserved delightful simplicity ye. Law own advantage furniture continual sweetness bed agreeable perpetual. Oh song well four only head busy it. Afford son she had lively living. Tastes lovers myself too formal season our valley boy. Lived it their their walls might to by young."; 

期待される結果は、再びそれを行うには

a => again, ask 
c => civil 
e => end 
m => might 
s => spoil 
w => Why 

Answer 1

非常に多くの方法を台無しに...私はちょうど私が少し興味深い（ちょうど "おかしいスクリプト" ;-)より見つけたものを選んだ

これは、例えば、

---の---
シーズン
彼女
彼女
彼女
シンプル

または

<?php 
$text = "Why end might ask civil again spoil. She dinner she our horses depend. Remember at children by reserved to vicinity. In affronting unreserved delightful simplicity ye. Law own advantage furniture continual sweetness bed agreeable perpetual. Oh song well four only head busy it. Afford son she had lively living. Tastes lovers myself too formal season our valley boy. Lived it their their walls might to by young."; 

// build 
$result = []; 
foreach(preg_split('![^a-zA-Z]+!', $text, -1, PREG_SPLIT_NO_EMPTY) as $word) { 
    // here goes the case-sensitivity; it's all lower-case from now on.... 
    $word = strtolower($word); 
    $char = $word[0]; 
    // not storing as the element's value but the key 
    // takes care of doublets 
    $result[$char][$word] = true; 
} 

// get keys & sort 
$result = array_map(
    function($e) { 
     // remember? The actual words have been stored as the keys 
     $e = array_keys($e); 
     usort($e, 'strcasecmp'); 
     return $e; 
    }, 
    $result 
); 


// print 
var_export($result); 

Answer 2

私のソリューションは、すでにソートされた単語を最初の文字でフレーズに分割する正規表現の周りに構築されています。

(\w)
• ：次に単語の最初の文字に一致する文字（技術的には任意の「単語」の文字）、
• .*?一致捕捉基：（ひとつの文字の可能な最小数とすることができます単語、またはいくつかの）
• ($| (?!\\1))続く：最初のキャプチャグループと同じ文字が続くテキストまたはスペースないの一番最後。

$text = "Why end might ask civil again spoil. She dinner she our horses" 
    . " depend. Remember at children by reserved to vicinity. In affronting" 
    . " unreserved delightful simplicity ye. Law own advantage furniture" 
    . " continual sweetness bed agreeable perpetual. Oh song well four only" 
    . " head busy it. Afford son she had lively living. Tastes lovers" 
    . " myself too formal season our valley boy. Lived it their their walls" 
    . " might to by young."; 

// Split the text into individual words and sort them, case insensitively. 
$words = preg_split("[\W+]", $text); 
natcasesort($words); 

// Join the sorted words back together and break them into phrases by 
// initial letter. 
preg_match_all("[(\w).*?($| (?!\\1))]i", implode(" ", $words), $matches); 

// Arrange the phrases into an array keyed by lower-case initial letter, 
// split them back into an array of words. 
$words = array_combine(
    array_map("strtolower", $matches[1]), 
    array_map(function($phrase){ return explode(" ", trim($phrase)); }, 
       $matches[0])); 

var_dump($words); 

/* 
array (size=19) 
    'a' => 
    array (size=7) 
     0 => string 'advantage' (length=9) 
     1 => string 'Afford' (length=6) 
     2 => string 'affronting' (length=10) 
     3 => string 'again' (length=5) 
     4 => string 'agreeable' (length=9) 
     5 => string 'ask' (length=3) 
     6 => string 'at' (length=2) 
    'b' => 
    array (size=5) 
     0 => string 'bed' (length=3) 
     1 => string 'boy' (length=3) 
     2 => string 'busy' (length=4) 
     3 => string 'by' (length=2) 
     4 => string 'by' (length=2) 
    ... 
*/