Array compare if value exist add value otherwise 0 in indexes - php

Question

After 1st answer my output is one value missing my ratting lenght is According to Array2 not Array !,,,,,Input:
I want this output:
My output is getting 0,0,0,0
I want to compare two arrays with different length, if matches the add the value, if not then add "0" and skip after assign and go to first loop
My code:
for($i=0;$i<count($custt1);$i++){
for($j=0;$j<count($items);$j++){
if($items[$j]==$custt1[$i]){
$x[$j]=$rating[$j];
}
else{
$x[$j]=0;
}
}
for($j=0;$j<count($items1);$j++){
if($items1[$j]==$custt1[$i]){
$y[$j]=$rating1[$j];
}
else{
$y[$j]=0;
}
}
}
I want to save in x and y array if value present then add rating otherwise "0" and go to first loop but I am facing in index 0 if value not present add 0 and on 8 indexes. Hope you understand my explanation and please help me to solve this.
now my output is by applying 1st answer
<br />
<b>Notice</b>: Undefined offset: 5 in
<b>C:\xampp\htdocs\Rest\new2.php</b> on line
<b>79</b>
<br />
Array
(
[0] => 1
[1] => 2
[2] => 3
[3] => 0
[4] => 5
[5] =>
[6] => 0
[7] => 0
[8] => 0
)
Because i am implementing recommendation system
<?php
$dbhost = "localhost";
$dbuser = "root";
$dbpass = "";
$dbname = "hfc";
$array;
$connection = mysqli_connect($dbhost, $dbuser, $dbpass, $dbname);
if ($connection) {
$sql1="SELECT item_name
from feedback
GROUP BY item_name";
$sql="SELECT customer_email_address AS customeremail,
GROUP_CONCAT(
DISTINCT CONCAT(cook_email_address,'-',item_name,'-',rating)
) AS uniqueItem
FROM feedback
GROUP BY customer_email_address";
$result = mysqli_query($connection, $sql);
while ($row = mysqli_fetch_array($result))
{
$customer_email[] = $row['customeremail'];
$cust1[]= $row['uniqueItem'].",";
}
$item[] = explode(",",$cust1[0]);
for($i=0;$i<count($item[0])-1;$i++){
$item_rating[] = explode("-",$item[0][$i]);
}
print_r ($item_rating);
for($i=0;$i<count($item_rating);$i++){
$items[]=$item_rating[$i][1];
$rating[]=$item_rating[$i][2];
}
$item1[] = explode(",",$cust1[1]);
for($i=0;$i<count($item1[0])-1;$i++){
$item_rating1[] = explode("-",$item1[0][$i]);
}
print_r ($item_rating1);
for($i=0;$i<count($item_rating1);$i++){
$items1[]=$item_rating1[$i][1];
$rating1[]=$item_rating1[$i][2];
}
$result1 = mysqli_query($connection, $sql1);
while ($row = mysqli_fetch_array($result1))
{
$custt1[]= $row['item_name'];
}
print_r ($custt1);
print_r ($items);
$output = array();
foreach ($custt1 as $i =>$item) {
if (in_array($item, $items)) {
$output[] = $rating[$i];
} else {
$output[] = 0;
}
}
print_r ($output);
for($i=0;$i<count($custt1);$i++){
for($j=0;$j<count($items);$j++){
if($items[$j]==$custt1[$i]){
$x[$i]=$rating[$j];
}
else{
$x[$i]=0;
}
}
for($j=0;$j<count($items1);$j++){
if($items1[$j]==$custt1[$i]){
$y[$j]=$rating1[$j];
}
else{
$y[$j]=0;
}
}
}
print_r ($x);
print_r ($y);
for($i1=0;$i1<count($custt1);$i1++)
{
$array[]=explode(",",$custt1[$i1]);
}
// echo count($array);
// print_r($custt1)."<br>";
/*for($i=0;$i<count($array);$i++)
{
for($y=1;$y<count($array);$y++)
{
$pearson=Corr($array[$i],$array[$y],$c=count($array));
}
}*/
$pearson=Corr($array);
echo $pearson;
}
function Corr(&$arr){
$x=$arr[0];
$y=$arr[1];
$length=count($x)-1;
$mean1=array_sum($x)/ $length;
$mean2=array_sum($y)/ $length;
echo $mean1."mean of x";
echo $mean2."mean of y";
echo "\n";
//echo $mean2;
$a=0;
$b=0;
$axb=0;
$a2=0;
$b2=0;
for($i=0;$i<$length;$i++)
{
$a=$x[$i]-$mean1;
$b=$y[$i]-$mean2;
$axb=$axb+($a*$b);
$a2=$a2+ pow($a,2);
$b2=$b2+ pow($b,2);
$corr= $axb / sqrt($a2*$b2);
}
return $corr;
}
?>

Answer 1

Use in_array() to tell if the element of array 1 is in array 2.
$output = array();
foreach ($array1 as $i => $item) {
if (in_array($item, $array2)) {
$output[] = $rating[$i];
} else {
$output[] = 0;
}
}