字符串中的前 10 个 PHP 关键字

Question

当我的目标是呈现字符串中的前 10 个单词时，我制作了一个复杂的关键字数组。

b) 我只想介绍一个重要的词，而不是像“The,That,to,a...”这样的词。

完整代码：

$str= $db_tag;
    $tok = strtok($str, ", ");
    $subStrStart = 0;

    while ($tok !== false) {
        preg_match_all("/\b" . preg_quote($tok, "/") . "\b/", substr($str, $subStrStart), $m);
        if(count($m[0]) >= 10)
            echo "'" . $tok . "' found more than 10 times, exaclty: " . count($m[0]) . "<br>";
        $subStrStart += strlen($tok);
        $tok = strtok(", ");
    }    

我的字符串：

$db_tag="The,Economy,Could,Be,Given,A,Post,Brexit,Vote,Vote,Vote,Vote,Boost,This,Week,As,Expectations,Mount,That,The,Bank,Bank,Bank,Bank,Bank,Of,England,England,England,England,England,Will,Cut,Economy,Economy,Economy,Brexit,Brexit,Brexit,Brexit";

提前致谢。

Answer 1

试试这个：

$db_tag = "The,Economy,Could,Be,Given,A,Post,Brexit,Vote,Vote,Vote,Vote,Boost,This,Week,As,Expectations,Mount,That,The,Bank,Bank,Bank,Bank,Bank,Of,England,England,England,England,England,Will,Cut,Economy,Economy,Economy,Brexit,Brexit,Brexit,Brexit";

$stopWords = array(
    "the", "to", "in", "a", "of", "is", "that", "will", "and", "be"
);

// Convert to array and filter out stopwords.
$words = array_filter(function ($value) {
    return !in_array($value, $stopwords);
}, explode(',', $db_tag));

$counts = array_count_values($words);
asort($counts);
$topTen = array_reverse(array_slice($counts, -10, null, true));

var_dump($topTen);

你应该看到：

php > var_dump($topTen);
array(10) {
  ["England"]=>
  int(5)
  ["Bank"]=>
  int(5)
  ["Brexit"]=>
  int(5)
  ["Economy"]=>
  int(4)
  ["Vote"]=>
  int(4)
  ["The"]=>
  int(2)
  ["Post"]=>
  int(1)
  ["Given"]=>
  int(1)
  ["A"]=>
  int(1)
  ["Could"]=>
  int(1)
}

首先，我们用explode() 将字符串拆分成一个数组。然后，我们返回一个带有 array_count_values() 的唯一数组值数组，与它们在字符串中出现的次数相关联。

接下来，我们使用 asort() 按值对数组进行就地排序。然后，我们使用array_slice() 从数组中切出最后10 个元素（最高的元素），然后使用array_reverse() 将其反转，以降序排列（可选）。

Answer 2

如果“Top 10”是指字符串中的“10 个最常用词”，用逗号, 分隔，您可以这样做：

$string = "The,Economy,Could,Be,Given,A,Post,Brexit,Vote,Vote,Vote,Vote,Boost,This,Week,As,Expectations,Mount,That,The,Bank,Bank,Bank,Bank,Bank,Of,England,England,England,England,England,Will,Cut,Economy,Economy,Economy,Brexit,Brexit,Brexit,Brexit";

//Create array of words split by ","
$words = explode(",",$string);

//Create an empty array to hold data
$wordData = [];

foreach($words as $word){
    //Convert to lower case (for uniformity)
    $word = strtolower($word);

    //Add to an array if doesn't exist; if it does,
    //add to the number
    if(isset($wordData[$word])){
        $wordData[$word]++;
    } else $wordData[$word] = 1;
}

//Order $wordData array by number
arsort($wordData);

print_r($wordData);

这将输出：

数组 ( [英格兰] => 5 [银行] => 5 [英国脱欧] => 5 [投票] => 4 [经济] => 4 [该] => 2 [期望] => 1 [意志] => 1 [的] => 1 [那个] => 1 [安装] => 1 [这个] => 1 [作为] => 1 [周] => 1 [提升] => 1 [帖子] => 1 [A] => 1 [给定] => 1 [是] => 1 [可以] => 1 [切] => 1 )

---

过滤掉特定的词：

//Establish array of words to filter
$filterWords = ["the", "is", "are", "of", "that"];

//Remove those words from the array created earlier
foreach($filterWords as $fw){
    if(isset($wordData[$fw])) unset($wordData[$fw]);
}

print_r($wordData);

这将输出：

数组 ( [england] => 5 [bank] => 5 [brexit] => 5 [vote] => 4 [economy] => 4 [expectations] => 1 [will] => 1 [mount] => 1 [this] => 1 [as] => 1 [week] => 1 [boost] => 1 [post] => 1 [a] => 1 [given] => 1 [be] => 1 [可以] => 1 [削减] => 1 )

Answer 3

你可以使用explode和一个数组：

$db_tag="The,Economy,Could,Be,Given,A,Post,Brexit,Vote,Vote,Vote,Vote,Boost,This,Week,As,Expectations,Mount,That,The,Bank,Bank,Bank,Bank,Bank,Of,England,England,England,England,England,Will,Cut,Economy,Economy,Economy,Brexit,Brexit,Brexit,Brexit";
$array = array();
foreach (explode(',', $db_tag) as $val) 
{
    if(!isset($array[$val]))
    {
        $array[$val] = 1;
    }
    else
    {
        $array[$val]++;
    }
}
arsort($array);
print_r($array);

将输出：

Array
(
    [England] => 5
    [Bank] => 5
    [Brexit] => 5
    [Vote] => 4
    [Economy] => 4
    [The] => 2
    [Expectations] => 1
    [Will] => 1
    [Of] => 1
    [That] => 1
    [Mount] => 1
    [This] => 1
    [As] => 1
    [Week] => 1
    [Boost] => 1
    [Post] => 1
    [A] => 1
    [Given] => 1
    [Be] => 1
    [Could] => 1
    [Cut] => 1
)

Answer 4

使用波纹管函数从字符串中提取搜索关键字

function getKeywords($string)
{
    $string = "North Korea has recently introduced a sweeping new law which seeks to stamp out any kind of foreign influence - harshly punishing anyone caught with foreign films, clothing or even using slang. But why?Yoon Mi-so says she was 11 when she first saw a man executed for being caught with a South Korean drama.    His entire neighbourhood was ordered to watch. If you didn't, it would be classed as treason, she told the BBC from her home in Seoul.        The North Korean guards were making sure everyone knew the penalty for smuggling illicit videos was death. I have a strong memory of the man who was blindfolded, I can still see his tears flow down. That was traumatic for me. The blindfold was completely drenched in his tears. ";
    $vowels = ["a","e","i","o","u"];
    $ignore = ["th","thy","sh"];
    $string = str_replace($vowels, "", $string);

//Create array of words split by ","
$words = explode(" ",$string);

//Create an empty array to hold data
$wordData = [];

foreach($words as $word){
    //Convert to lower case (for uniformity)
    $word = trim(strtolower($word));
    if(strlen($word)<3)
        continue;
    if(array_search($word, $ignore)>-1) continue;
    //Add to an array if doesn't exist; if it does,
    //add to the number
    if(isset($wordData[$word])){
        $wordData[$word]++;
    } else $wordData[$word] = 1;
}

//Order $wordData array by number
arsort($wordData);

$x = (array_keys($wordData));
$result = "";
$count = 0;

foreach ($wordData as $key => $value) {
    $count++;
    $result .=$key . ",";
    if($count==10) break;
}

return $result;
}