Question

我有一个长数组（1x75000！）的字符串数据。在这个数组中，有重复的字符串。我想找到数组索引和每个重复字符串的数量。 E.g。

A = [＆＃39; ABC＆＃39; ＆＃39; EFG＆＃39; ＆＃39; HIJ＆＃39; ＆＃39; ABC＆＃39; ＆＃39; HIJ＆＃39; ＆＃39; EFG＆＃39; ＆＃39; KLM＆＃39;]; 答案应该是： 2次＆＃39; abc＆＃39;在数组索引1,4处 2次＆＃39; efg＆＃39;在数组索引2,6 2次＆＃39; hij＆＃39;在数组索引3,5 1次＆＃39; klm＆＃39;在数组索引7

注意数组的大尺寸（1x75000）

Answer 1

此代码应该有效：

<?php

$array = array('abc','wrerwe','wrewer','abc');
$out = array();

foreach ($array as $key => $value) {
    if (!isset($out[$value]))  {
        $out[$value]['nr'] = 0;
        $out[$value]['index'] = array();        
    }
    ++$out[$value]['nr'] ;
    $out[$value]['index'][] = $key;
}


foreach ($out as $k => $v) {
    echo "item ".$k." repeats ".$v['nr'].' times at positions: ';
    echo implode(', ', $v['index']);
    echo "<br />";
}

但到目前为止，我还没有在这么大的阵列上测试过。事实上，我认为你不应该在这么大的数组上运行。你应该把它分成较小的数组。

我使用代码（从How to create a random string using PHP?生成随机字符串的源代码）在75000数组上测试了它：

<?php

$array = randomTexts(75000);
$out =  array();

foreach ($array as $key => $value) {
    if (!isset($out[$value]))  {
        $out[$value]['nr'] = 0;
        $out[$value]['index'] = array();        
    }
    ++$out[$value]['nr'] ;
    $out[$value]['index'][] = $key;
}


foreach ($out as $k => $v) {
    echo "item ".$k." repeats ".$v['nr'].' times at positions: ';
    echo implode(', ', $v['index']);
    echo "<br />";
}


function randomTexts($nr) {
    $out = array();
    $validString = 'abddefghihklmnopqrstuvwzyx';
    for ($i=0; $i< $nr; ++$i) {
        $len = mt_rand(5,10);        
           $out[] = get_random_string($validString, $len);
    }
    return $out;
}


function get_random_string($valid_chars, $length)
{
    // start with an empty random string
    $random_string = "";

    // count the number of chars in the valid chars string so we know how many choices we have
    $num_valid_chars = strlen($valid_chars);

    // repeat the steps until we've created a string of the right length
    for ($i = 0; $i < $length; $i++)
    {
        // pick a random number from 1 up to the number of valid chars
        $random_pick = mt_rand(1, $num_valid_chars);

        // take the random character out of the string of valid chars
        // subtract 1 from $random_pick because strings are indexed starting at 0, and we started picking at 1
        $random_char = $valid_chars[$random_pick-1];

        // add the randomly-chosen char onto the end of our string so far
        $random_string .= $random_char;
    }

    // return our finished random string
    return $random_string;
}

它似乎也有效，但需要几秒钟

如何在matlab中查找字符串数组中重复字符串的数量及其数组索引

1 个答案: