Advice/PHP Internal Function?? - Get last 20 associative array values?

[thepip3r]

I'm probably just rusty and can't recall but is there a way to mathematically get the last 20 values of a dynamically sized associative array? 

 

I realize I can remap the array with numeric indexes and then use that, I just wanted to make sure I'm not missing the easier (more efficient) way.

 

 

[wildteen88]

You could use array_slice

[thepip3r]

so array_slice() into a new array and count off of it's values correct?  Ty wildteen.

[wildteen88]

Yes you would use array_slice() like so

$last20 = array_slice($array, -20, 20, true);

 

$last20 will store a copy of the last 20 items in your array ($array);

[thepip3r]

ah even better... i was thinking about using it to create an entirely new indexed array and then using a for() loop to loop through... tyvm for the clarification.

[nrg_alpha]

With the use of array_slice, the last 20 entries will be retained (including their indices.. so using an array with say 25 indices, the new array will start at index 5 and go through to 24:

 

$arr = array(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25);
$last20 = array_slice($arr, -20, 20, true);
echo '<pre>'.print_r($last20, true); // index 5 thru 24, with values 6 thru 25

 

Not sure if this is a big deal or not.. but if you want to have the indices renamed from from 0 instead, you can use array_splice instead:

$arr = array(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25);
$last20 = array_splice($arr, -20);
echo '<pre>'.print_r($last20, true); // index 0 thru 19, with values from 6 thru 25

[thepip3r]

nrg... even better... tyvm for the comment