php array trouble

[lj11]

if I have an array that looks like this:

 

$taken=array(3,6,5,2,4);

 

how do i create an array that has all numbers from 1 to 9 in it that are not any of the values in the $taken array?

 

I guess it impossible, thanks anyway

[matthewhaworth]

<?php
$taken = array(3, 6, 5, 2, 4);
$nottaken = array();
for($i=1; $i<10; $i++)
{
    if(!in_array($i, $taken))
    {
        $nottaken[] = $i;
    }
}

print_r($nottaken);

?>

 

Something like that.

[kenrbnsn]

You really should look at the different array functions in the manual, especially at the array_diff() function.

 

Ken

[matthewhaworth]

<?php
$dataset = array(1, 2, 3, 4, 5, 6, 7, 8, 9);
$taken = array(3, 6, 5, 2, 4);

$nottaken = array_diff($dataset, $taken);

print_r($nottaken);

?>

 

Using what Ken said. Hey, you learn something new everyday when you help people.

 

However, there is a disadvantage to this because the array will have indexes that aren't.. together.. if you will. I.e. when I ran that I got:

 

Array ( [0] => 1 [6] => 7 [7] => 8 [8] => 9 ) 

 

Instead of the other way were I got:

 

Array ( [0] => 1 [1] => 7 [2] => 8 [3] => 9 ) 

 

[.josh]

<?php
$dataset = array(1, 2, 3, 4, 5, 6, 7, 8, 9);
$taken = array(3, 6, 5, 2, 4);

$nottaken = array_diff($dataset, $taken);

print_r($nottaken);

?>

 

Using what Ken said.  Hey, you learn something new everyday when you help people.

 

However, there is a disadvantage to this because the array will have indexes that aren't.. together.. if you will.  I.e. when I ran that I got:

 

Array ( [0] => 1 [6] => 7 [7] => 8 [8] => 9 ) 

 

Instead of the other way were I got:

 

Array ( [0] => 1 [1] => 7 [2] => 8 [3] => 9 ) 

 

 

array_values ftw

[matthewhaworth]

<?php
$dataset = array(1, 2, 3, 4, 5, 6, 7, 8, 9);
$taken = array(3, 6, 5, 2, 4);

$nottaken = array_diff($dataset, $taken);
$nottaken = array_values($nottaken);

print_r($nottaken);
?>

 

Does in fact output:

 

Array ( [0] => 1 [1] => 7 [2] => 8 [3] => 9 ) 

 

I don't really like that solution though lol, I don't know why. I don't imagine it to be much faster than the first solution because in the background it's doing the same thing, except this one has to run an extra function.. so if anything, it's slower.. but the speed differences would be so small that it doesn't really matter.. pick whichever.. though to be honest, I think the TS has given up on this thread because he/she didn't get a reply within 10 minutes lol.

[.josh]

except that it's less lines of code and more readable...

[lj11]

THANKYOU  ALL SO MUCH!!

 

:D ;D

[Barand]

However, there is a disadvantage to this because the array will have indexes that aren't.. together.. if you will.  I.e. when I ran that I got:

 

Array ( [0] => 1 [6] => 7 [7] => 8 [8] => 9 ) 

 

Instead of the other way were I got:

 

Array ( [0] => 1 [1] => 7 [2] => 8 [3] => 9 ) 

 

 

Before worrying about gaps in the keys you need to establish whether or not it matters. eg you may just want to do

 

echo join (', ', $nottaken);

 

in which case who cares?