如何在php中评分

Question

我正在尝试根据获得的最高平均分数对一些分数进行评分。 这是我的脚本$scores_AND_ID = 'M2377O=100,M2727B=100,M5821K=100,M7492F=97.75,M7973O=96,M3487I=94,M7969O=93.13,M1452V=92.5,M4653O=92.38,M4158J=92.25,M2881A=89.38,M6112S=28.63,';    $out_score = chop($scores_AND_ID, ',');    $rr2 = explode(",", $out_score);    $array_un = array_unique($rr2);    foreach ($array_un as $key => $value) {        if ($value == "") {            continue;        }        $postion = positionNumbers($key);//1st,2nd,3rd function        $sec = explode("=", $value);        rsort($sec);        $stdntID = $sec[0]; //Student number        $stdntAV = $sec[1]; //Student Average        mysql_query("UPDATE score_table SET grade='$postion' WHERE avg='$stdntAV' ");    }我正在使用 foreach 键来分配成绩位置，但无法正常工作。这是我的结果这是我需要实现的目标。    1. 100---1st    2. 100---1st    3. 100---1st    4. 98---4th    5. 89.5--5th    6. 89---6th    7. 89---6th    8. 80---8th

Answer 1

如果已经设置了成绩，则不应更新您的记录。如果您打印查询而不是执行它，您将看到您设置了第 1 级，然后您用第 2 级覆盖它，然后用第 3 级覆盖它。

Answer 2

我认为你想要的代码是这样的：

<?php

$scores_AND_ID = 'M7492F=97.75,M7973O=96,M3487I=94,M2377O=100,M2727B=100,M5821K=100,M7969O=93.13,M1452V=92.5,M4653O=92.38,M4158J=92.25,M2881A=89.38,M6112S=28.63,';

// Gets all of the entries from the source string

$scores_array = array_unique(array_filter(explode(',', $scores_AND_ID)));

// Sets up an associative array of values (student id => score)

$score_map = [];

foreach ($scores_array as $record) {

    [ $student_id, $score ] = explode('=', $record);

    $score_map[$student_id] = $score;

}

// Ensure values are sorted numerically descending

uasort($score_map, function ($a, $b) {

    if ($a > $b) {

        return -1;

    }

    if ($a == $b) {

        return 0;

    }

    return 1;

});

// Gets the maximum value from the scores

$previous_score = max(array_values($score_map));

$rank = 1;

$incrementer = 0;

foreach ($score_map as $student => $score) {

    // If the score hasn't changed from it's previous value

    // we increment a counter instead of the rank

    if ($score == $previous_score) {

        $incrementer++;

    // Once it's changed, we update the rank based on the incrementer

    // and then reset the incrementer

    } else {

        $rank += $incrementer;

        $incrementer = 1;

    }

    $previous_score = $score;

    // Updating database is left as an exercise to the reader

}