Php 数组中最常出现的字符？

请帮助我创建一个函数来解析以下数组，并返回一个数组，该数组包含最常见的字符，不区分大小写，不包括特殊字符，计数输入

    $sentences = [
    0 => 'The tiger is the national animal of India',
    1 => 'The tiger is a large carnivorous mammal that roams the forests',
    2 => 'The tiger feeds on animals that also live in the forest',
    3 => 'The tiger does have a coat of orange with black stripes',
    4 => 'Tigers, regardless of their subspecies, are carnivorous animals',
    5 => 'The tiger is a protected species',
    ];

The code should output the following result: 

    Array
    (
    [0] => Array
    (
    [sentence] => The tiger is the national animal of India
    [character] => i
    [occurrences] => 6
    )

    [1] => Array
    (
    [sentence] => The tiger is a large carnivorous mammal that roams the forests
    [character] => a
    [occurrences] => 7
    )

    [2] => Array
    (
    [sentence] => The tiger feeds on animals that also live in the forest
    [character] => e
    [occurrences] => 7
    )

    [3] => Array
    (
    [sentence] => The tiger does have a coat of orange with black stripes
    [character] => e
    [occurrences] => 6
    )

    [4] => Array
    (
    [sentence] => Tigers, regardless of their subspecies, are carnivorous animals
    [character] => s
    [occurrences] => 8
    )

    [5] => Array
    (
    [sentence] => The tiger is a protected species
    [character] => e
    [occurrences] => 6
    )

    )

我试过了

foreach($sentences as $sentence) {
    $value = array_count_values($sentence);
}

请帮助我为上述目的创建一个函数

您可以使用该函数对每个项目应用函数。在该函数中，您可以将字符串转换为小写，拆分数组中的字符并删除空格，以便使用。然后，您可以使用对数组进行排序以保持键关联，并在顶部获得使用最多的字符。最后，您可以使用和重置来获取数组的第一个键和第一个值：

$sentences = [
  0 => 'The tiger is the national animal of India',
  1 => 'The tiger is a large carnivorous mammal that roams the forests',
  2 => 'The tiger feeds on animals that also live in the forest',
  3 => 'The tiger does have a coat of orange with black stripes',
  4 => 'Tigers, regardless of their subspecies, are carnivorous animals',
  5 => 'The tiger is a protected species',
];

$out = array_map(function($value) {
    $chars = array_filter(str_split(strtolower($value)),'trim');
    $vals = array_count_values($chars);
    arsort($vals);
    $keys = array_keys($vals);
    return [
        'sentence' => $value,
        'character' => reset($keys),
        'occurrences' => reset($vals),
    ];
}, $sentences);
print_r($out) ;

产出：

Array (
    [0] => Array (
            [sentence] => The tiger is the national animal of India
            [character] => i
            [occurrences] => 6
        )
    [1] => Array (
            [sentence] => The tiger is a large carnivorous mammal that roams the forests
            [character] => a
            [occurrences] => 7
        )
    [2] => Array (
            [sentence] => The tiger feeds on animals that also live in the forest
            [character] => e
            [occurrences] => 7
        )

    [3] => Array (
            [sentence] => The tiger does have a coat of orange with black stripes
            [character] => e
            [occurrences] => 6
        )

    [4] => Array (
            [sentence] => Tigers, regardless of their subspecies, are carnivorous animals
            [character] => s
            [occurrences] => 8
        )

    [5] => Array (
            [sentence] => The tiger is a protected species
            [character] => e
            [occurrences] => 6
        )
)

要删除特殊字符，请执行以下操作：

$chars = array_filter(str_split(strtolower($value)),function($val){
    return trim(preg_replace('~\W+~', '', $val));
});

我会使用preg_match_all和一次匹配一个字母或数字的模式来提取一个字符数组，然后使用数组计数值查找出现的次数，按出现的次数降序排列数组，然后提取第一个键和第一个值，它们表示出现的最高字母的字符和计数

代码：演示：

使用

我使用count_chars将出现次数绘制为$counts，并使用max获取最大出现次数。如果出现次数小于max，则从数组中删除ASCII代码，因为可能有多个字符具有相同的出现次数

通过使用chr将剩余的ASII代码转换回字符

<?php
    foreach ($sentences as $sentence){
    $string = strtolower(preg_replace('/\s+/', '', $sentence));
    $counts = count_chars($string, 1);
    $max = max($counts);
    foreach ($counts as $key => $count) {
        if ($count < $max) {
            unset($counts[$key]);
        }
    }
    $characters = array_map(function($item){
           return chr($item);
        }, array_keys($counts));
    $result[] = [
        'sentence' => $sentence,
        'character' => implode(',', $characters),
        'occurrences' => $max
    ];
}

echo '<pre>', print_r($result) ,'<pre>';

---

演示：

您是否先尝试自己做？告诉我们你尝试了什么。不，这是为我的项目，然后，你已经尝试解决它，不是吗？你只是从php手册复制它。请发布您尝试过的内容。始终通过编辑而不是评论向您的问题添加问题详细信息。请在编辑您的问题后删除您的评论。是否删除特殊注释characters@sarinsurendran你说的特殊字符是什么意思？如果句子包含特殊字符，它不会被算作最常见的特殊字符@etc@sarinsurendran您应该使用除trim之外的另一个函数是array_filter函数。也许是一个自定义函数来删除它们。@sarin我的方法更干净/更直接。是否也要包括数字？请回答我的问题。你要电话号码吗？下划线？是的，数字和下划线避免删除特殊字符。那么我将调整我的答案以包括数字。沙林·苏伦德兰请为新问题创建新帖子

$sentences = [
0 => 'The tiger is the national animal of India',
1 => 'The tiger is a large carnivorous mammal that roams the forests',
2 => 'The tiger feeds on animals that also live in the forest',
3 => 'The tiger does have a coat of orange with **a** black stripe',
4 => 'Tigers, regardless of their subspecies, are carnivorous animals',
5 => 'The tiger is a protected species',
];

<?php
    foreach ($sentences as $sentence){
    $string = strtolower(preg_replace('/\s+/', '', $sentence));
    $counts = count_chars($string, 1);
    $max = max($counts);
    foreach ($counts as $key => $count) {
        if ($count < $max) {
            unset($counts[$key]);
        }
    }
    $characters = array_map(function($item){
           return chr($item);
        }, array_keys($counts));
    $result[] = [
        'sentence' => $sentence,
        'character' => implode(',', $characters),
        'occurrences' => $max
    ];
}

echo '<pre>', print_r($result) ,'<pre>';

    Array
(
    [0] => Array
        (
        [sentence] => The tiger is the national animal of India
        [character] => i
        [occurrences] => 6
    )

    [1] => Array
        (
            [sentence] => The tiger is a large carnivorous mammal that roams the forests
            [character] => a
            [occurrences] => 7
        )

    [2] => Array
        (
            [sentence] => The tiger feeds on animals that also live in the forest
            [character] => e
            [occurrences] => 7
        )

    [3] => Array
        (
            [sentence] => The tiger does have a coat of orange with a black stripe
            [character] => a,e **<== multiple characters**
            [occurrences] => 6
        )

    [4] => Array
        (
            [sentence] => Tigers, regardless of their subspecies, are carnivorous animals
            [character] => s
            [occurrences] => 8
        )

    [5] => Array
        (
            [sentence] => The tiger is a protected species
            [character] => e
            [occurrences] => 6
        )

)

$string = strtolower(preg_replace('/[^A-Za-z]/', '', $sentence));