php remove value from array - php

Question

Hi I need help in removing values from an array using a recursive function
$array = [0] => testing,testing1
[1] => testing,testing1,testing2
[2] => testing,testing1,testing2,testing3
[3] => testing,testing1,testing2,testing3,tesing4
[4] => testing,testing1,testing2,testing3,tesing4
[5] => testing,testing1,testing2,testing3,tesing4
[6] => testing,testing1,testing2,testing3,tesing4
[7] => testing,testing1,testing2,testing3,tesing4
I need to check the array count, ie if count(array[0]) == count(array[1]),then reutrn array
else unset(array[value]);
From the above array I have to remove array[0],[1],[2] and return rest of the array values.
I've tried the below code
$idx =10;
$separtor =',';
function array_delete($idx, $array,$separtor) {
$finalvalue = array();
for ($i = 0; $i < $idx; $i++) {
$values = explode($separtor, $array[$i]);
$valuesnext = explode($separtor, $array[$i+1]);
if(count($values) != count($valuesnext) )
{
unset($array[$i]);
// reset($array);
// array_delete($idx, $array,$separtor);
if (is_array($array)) $array = array_delete($idx, $array,$separtor);
$finalvalue = $array;
}else
{
}
//echo $i;
}
return $finalvalue;
//(is_array($array)) ? array_values($array) : null;
//array_delete($idx, $array,$separtor);
}
I'm getting Notice: Undefined offset: 0 when trying calling recursive, going to infinite loop

Answer 1

Do you want to keep the sub-arrays that have the most items? Your descriptions appear to say this.
If so, something like the following would suffice.
// Get maximum number of items in the arrays
$max_count = max(array_map('count', $array));
// Keep only those arrays having $max_count items
$filtered = array_filter($array, function ($a) use ($max_count) {
return count($a) === $max_count;
});
Aside: if you need the filtered array to have zero-based keys, call array_values() on it.
See an example running online.

Answer 2

If I understand correctly, you want to filter the array such that any value in the final array is of the same length as the last element in the source array. In order to avoid mutating an array while iterating over it, this technique builds a fresh array with the elements that match your criteria.
$matchLength = count($mainArray[count($mainArray) - 1]);
$resultArray = array();
for($i = 0; $i < count($mainArray); $i++) {
if(count($mainArray[$i]) == $matchLength) {
$resultArray[] = $mainArray[$i];
}
}
If you happen to be using PHP 5.3 or greater, you can do this quicker with closures and array_filter:
$matchLength = count($mainArray[count($mainArray) - 1]);
$resultArray = array_filter($mainArray, function($element){return count($element) == $matchLength});
Double check the code, I haven't been writing PHP lately, so this is just an idea.

Answer 3

According to the description you gave, it could be just made (check the count of the current and the provious one, if they don't match, remove the previous one).
Example/Demo:
unset($prevKey);
$count = array();
foreach (array_keys($array) as $key) {
$count[$key] = count($array[$key]);
if (isset($prevKey) && $count[$prevKey] !== $count[$key]) {
unset($array[$prevKey]);
}
$prevKey = $key;
}
If you need to re-iterate to take removals into account, a little goto can do the job Demo:
start:
######
unset($prevKey);
$count = array();
foreach (array_keys($array) as $key) {
$count[$key] = count($array[$key]);
if (isset($prevKey) && $count[$prevKey] !== $count[$key]) {
unset($array[$prevKey]);
goto start;
###########
}
$prevKey = $key;
}