CODEWITHSUNDEEP
phparrayssortingksort
Derek Gutierrez
Derek Gutierrez

Reputation: 638

PHP - How to sort the same array multiple times?

I am trying to make a simple script that will first put an array() into function so I can call on it multiple times to sort. Here is what my array looks like:

// I want this inside of a function so I can call on it:

$a = array(
    15 => "C",
    12 => "E",
    11 => "B",
    19 => "P",
    10 => "L",
    14 => "N",
    20 => "A"    
 );

// This is how I brought it into a function and formatted it:

function original_array($a){ 
    foreach($a as $key => $types) {
        print $key . " " . ":" . " " . $types . "<br />";
    }
}

I then just have to call original_array() and it prints out fine, but if I sort it once I cant sort it again. It will just print out the first sort:

// Print out array is is:

original_array();

// Then I print out array with sort():

sort($a);
original_array($a);

// But if I try and sort it again with different sort it doesn't work:

ksort($a);
original_array($a);

What am I doing wrong? I am somewhat new to PHP so your help is greatly appreciated.

UPDATE://

This is what I ended up doing. I should have read up on sort function a little more thoroughly. I was unaware that it destroyed the original pointers.

<?php  
// Original array: 
$a = array(
    15 => "C",
    12 => "E",
    11 => "B",
    19 => "P",
    10 => "L",
    14 => "N",
    20 => "A"   
);

// Array for sort() function:
$b = $a

function print_format($array){ 
    foreach($array as $key => $types) {
        print $key . " " . "=>" . " " . $types . "<br />";
    }
}    


print "Original";  
print_format($a);     

print "sort()";
sort($b);
print_format($b);

print "ksort()";
ksort($a);
print_format($a);    

print "asort()";
asort($a);  
print_format($a);    

print "krsort()";
krsort($a);  
print_format($a);

print "rsort()";
rsort($b);  
print_format($b);    

print "arsort()";
arsort($a);  
print_format($a);
?>

Upvotes: 1

Views: 1101

Answers (2)

Huseyin
Huseyin

Reputation: 1507

You can use reset() function. http://php.net/manual/en/function.reset.php

Upvotes: -1

animuson
animuson

Reputation: 54757

The normal sort() function destroys the keys for all values, so when it's sorted, each key is now numeric 0, 1, 2, 3. Therefore when you use ksort(), it does nothing because they're already numerically sorted by key.

Try using asort() to maintain key => value association when sorting by value. Then when you use ksort() later on, the keys still exist so you can sort in that way.

Upvotes: 4

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