Member Avatar for <M/>

How do I sort this loop? I can't sort it because I just began learning PHP, so I don't know as much as most of you users... Can anyone help me?

<?php
    $red = array();
    $x=0;
    $min=500;
    $max=2000;

    echo "<table border=\"1\">";
    for($row=1;$row<=20; $row++){

                    echo "<tr>\n";
                    //Need table ONE to have 20 by 20 rows & columns 
                    //Need the table to contain numbers between 900 - 2000 (Randomly)
                    //Table two will take table ONE and sorts it from Smallest to Biggest
                    //Table three will take table ONE and sorts it from Biggest to Smallest
                    //Table 4 will only show a (*) net to the Odd Numbers and (#) next to the Even Numbers 

                      for($col=1;$col<=20; $col++){
                          $x=rand($min,$max);
                                   $red[$row][$col] = $x;
                                   $blue[$row][$col]=$table[$row][$col];

                                     echo"<td>$x</td>\n"; 
                                                     }
                       echo "</tr>";
                                  }
    echo "</table>"; 




$blue= array();
echo "<table border=\"1\">";

for($row=1;$row<=20; $row++){
    echo "<tr>\n";

for($col=1;$col<=20;$col++){
    $blue[$row][$col] = $y;
    echo"<td>$y</td>\n";
    }
echo "</tr>";
}
echo "</table>"; 
?>

Basically what is in the comments inside the code is what I need to achieve... I unfortunately can't, so please help me!!!

  • 2 Contributors
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  • 1 Day Discussion Span
  • Latest Post Latest Post by somedude3488

Dani AI

Generated

A few quick fixes before a working approach: in @M/'s original code there are undefined variables ($table and $y) and some assignments that overwrite values unintentionally. PHP arrays are 0‑based, so building a flat list of 400 values and then chunking into rows avoids off‑by‑one confusion. 's hint about using a prebuilt set (range + shuffle) is useful if you want 400 unique numbers; if duplicates are acceptable, generate 400 random entries instead.

Concept: create a single flat array of 400 numbers (each 900–2000), split it into 20-element rows with array_chunk() to make a 20x20 grid, then render that grid. To get the sorted tables, copy the flat array, run sort() (ascending) or rsort() (descending) and chunk again. To mark odd/even, append '*' for odd and '#' for even when rendering.

Example (modern, self-contained):

<?php
$values = [];
for ($i = 0; $i < 400; $i++) {
    $values[] = function_exists('random_int') ? random_int(900, 2000) : mt_rand(900, 2000);
}

function render_table(array $grid, $markOddEven = false) {
    echo "<table border=\"1\">\n";
    foreach ($grid as $row) {
        echo "<tr>";
        foreach ($row as $n) {
            $suffix = $markOddEven ? ($n % 2 ? '*' : '#') : '';
            echo "<td>{$n}{$suffix}</td>";
        }
        echo "</tr>\n";
    }
    echo "</table>\n";
}

$grid = array_chunk($values, 20);
render_table($grid);                       // original random table

$asc = $values; sort($asc, SORT_NUMERIC);
render_table(array_chunk($asc, 20));      // ascending

$desc = $values; rsort($desc, SORT_NUMERIC);
render_table(array_chunk($desc, 20));     // descending

render_table($grid, true);                // odd (*) / even (#)
?>

Troubleshooting notes: use SORT_NUMERIC for numeric sorting to avoid string comparisons; sort functions modify arrays in place, so copy first if you need the original order preserved; random_int() requires PHP 7+, fall back to mt_rand() if necessary. If you need unique values only, follow 's idea: build range(900,2000), shuffle() it, then array_slice() the first 400 values.

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Member Avatar for somedude3488

Is this a homework assignment? If so, we will not just give you the answer. I will, however, help you find the answer yourself.

You will need the functions range(), shuffle(), and sort(). Look these up on php.net.

Member Avatar for <M/>

No, this isn't for a class of any sort... this is just me trying to figure out different ways of manipulating arrays...

Apparently I want to use a loop to sort these... you know how to set this up?

Thanks for the quick response!

Member Avatar for somedude3488

Pretty much you need to make an array filled with the numbers from 500-2000, then shuffle the array and display it using a loop. For the other tables, you run the array through a sort function to sort ascending/descending and display the same way you did above.

Member Avatar for <M/>

Can you write me a couple of lines on how to do it? Apparently, I have messed up numerous times today in making this work... do you mind helping?

Thanks again!

Member Avatar for somedude3488

Here is part of the code to get you started. In this case, I hate just giving code, but it is usually easier to show you.

<?php

$numbers = range(900,2000);
shuffle( $numbers );

//loop through $numbers and display in table

$numbers_asc = $numbers_desc = $numbers;

asort( $numbers_asc,SORT_NUMERIC );

//loop through $numbers_asc and display in table

arsort( $numbers_desc,SORT_NUMERIC );

//loop through $numbers_desc and display in table

?>

There might be some errors in there, I wrote it pretty quickly.

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