PHP - Creating An Array To Make A Graph (math)

Code: [Select]
if ($user['amount'] >= 15.00){
   $user['max_stars'] = 3;
}
Ok and

Code: [Select]
if ($user['amount'] >= 20.00){
   $user['max_stars'] = 4;
}How can I write a function that will loop through the 15,20,25,30,35, all the way up to 600$ or if the max_Stars get's up to 80?

I really don't want to have 80 if functions in my code :\

Having to go into somebody else's code yet again! Gah! Originally the totaling page just subtracted a flat discount. But now the client wants to be able to subtract percentage discounts and 'per item' discounts. In the discount table I added a field to determine whether the discount chosen is to be applied as flat off total, flat per item, % off total, and % off each item. I also entered a field that can have a class id, in case this discount is only for that class. (the intention being that otherwise the discount is on anything)

I've got a session variable that generates something like : Array ( [217] => 1 [215] => 2 )
meaning 1 person in class #217, and 2 people in class 215.

$_SESSION['s_to_be_added'] = array_filter($_POST['participantqty']);

Then on the page I'm concerned with, I've been trying to write the script. I know I still need some math stuff figured out
 But how do I take the array, do the math, and then generate an overall cost for the whole thing? and this is just  the discounting? I don't even have a clue how to work in delimiting it if there's a class id.. did any of that make sense?

Code: [Select]
<?php

// the above is the array I want to use to 
$passed_array = array_filter($_SESSION['s_to_be_added']);

// this is the discount 'code' the user entered.
$discount = mysql_escape_string($_POST['discount']);

// just a donation added after everything.
$donation = mysql_escape_string($_POST['donation']);

// finding the discount that matches the discount 'code' entered.
$query_selectAllItems_events = "SELECT discount_amount,discount_type,workshop_link_1 FROM tbl_discount where discount_value = '$discount'";

    $result_all_events = mysql_query($query_selectAllItems_events);
$numRows_all_events = mysql_num_rows($result_all_events);
$num=mysql_num_rows($result_all_events); 
$z_row = mysql_fetch_array($result_all_events);
        
        // this is just a number: 1, 20, 90 etc.
        $discount_amount = $z_row['discount_amount'];
        
        /*this is 1,2,3,4 - for each type of discount 1- flat 2- flat per item
        3- discount on all, 4- discount per item */
        $discount_type = $z_row['discount_type'];
        
        // the workshop id if the discount is onlyh for this workshop
        $discount_link_1 = $z_row['workshop_link_1'];
        
        // just a description
$discount_name = $z_row['discount_name'];

        
if ($discount_type ==1) {
            /* flat discount on total here */
            $total = mysql_escape_string($_POST['total']);

$final_total = ($total - $discount_amount);
$final_total = ($final_total + $donation);
        }
        
        elseif ($discount_type ==2)) {
            /*  discount per item total here */
$total = mysql_escape_string($_POST['total']);

$final_total = ($total - $discount_amount);
$final_total = ($final_total + $donation);
        
        }
        
        elseif ($discount_type ==3)) {
            /* percentage discount on total here */
$total = mysql_escape_string($_POST['total']);

$final_total = ($total * ($discount_amount/100));
$final_total = ($final_total + $donation);
        
        }
        
        elseif ($discount_type ==4)) {
            /* percentage discount per item here */
$total = mysql_escape_string($_POST['total']);

$final_total = ($total * ($discount_amount/100));
$final_total = ($final_total + $donation);
        
        }
        
        ?>

I have to take over somebody else's project. So I have the combination of being a beginner, not understanding their code well, and not experienced with arrays. I'm in over my head.

I have an array passed to the page, that would be something like this:

Array ( [215] => [213] => 1 [212] => 2 [214] => )
the user chose 1 person in 213, and 2 people in 212

 and I basically need to break it apart to do math like this:

(#people x cost of 213 = totalcostA )  +  (# people x cost of 212 = totalcostB)   =  total

The broken down data goes into the database, and the total is used for the cart.

I've taken suggestions and gotten to this jumbled mess:
Code: [Select]
$ids = $_POST['workshop_id'];
print_r($_POST['participantqty']);
// the above shows the arrays  are sending to this page and printing correctly: Array ( [215] => [213] => 1 [212] => 2 [214] => )
foreach ($_POST['workshop_id'] as $id){
   $qty = $_POST['participatqty'][$id];
}

if(sizeof($_POST['workshop_id'])) {
// loop through array
$number = count($ids);
for ($i=0; $i<=$number; $i++)
{
    // store a single item number and description in local variables
    $itno = $ids[$i];
    $qty_insert = $qty[$i];

   

$query_insertItemWorkshop = "INSERT INTO tbl_registration_workshop (registration_id, workshop_id, regworkshop_qty) VALUES ('$reg_id', '$itno', '$qty_insert')";
$dberror = "";
$ret = mysql_query($query_insertItemWorkshop);
$query_selectAllItems_events = 'SELECT * FROM tbl_workshops where workshop_id = '.$itno;
@$result_all_events = mysql_query($query_selectAllItems_events);
@$numRows_all_events = mysql_num_rows($result_all_events);
@$num=mysql_num_rows($result_all_events);
@$z_row = mysql_fetch_array($result_all_events);
// I want the below to work, but it won't until I can figure out how to break it all down.
$qty_total=$qty_insert*$z_row['workshop_price'];
$total = $total + $qty_total;

   
    if ($ids[$i] <> '') {

// I want the info to also appear below, but  can't until I figure out how to break them down.

    echo $total_students;
echo "<tr><td valign=top><b>Description:</b> ". $z_row['workshop_title'] ."</td><td align='right' colspan='2' width=300 valign=top>" . $qty_insert . " at ". $z_row['workshop_price'] ." each: &nbsp;</td><td valign=top> $". $qty_total ."</td></tr>";

I am retrieving values in form of array from a database table and out of the I have to build multidimensional array depending upon the parent->child relationship in the same array.
The result is as
 
    => Array
                (
                    => Array
                        (
                            [label] => Shirt
                            [uri] => #
                        )

                    [1] => Array
                        (
                            [label] => Jeans
                            [uri] => #
                        )

                    [2] => Array
                        (
                            [label] => Lowers
                            [uri] => #
                        )

                    [3] => Array
                        (
                            [label] => T-Shirts
                            [uri] => #
                        )

                    [4] => Array
                        (
                            [label] => cotton shirt
                            [uri] => #
                        )

                    [5] => Array
                        (
                            [label] => Trousers
                            [uri] => #
                        )

                )
each is related to some parent-id.
Can any body me any idea.

My longest post of the year..... (thank you in advance for scrolling 😀)
Here is what my $_POST array looks like using print_r($_POST)

Array
(
    [newQuantity77777] => 3
    [newPrice77777] => 5.00
    [usedQuantity77777] => 1
    [usedPrice77777] => 3.99
    [total77777] => 18.99
    [newQuantity88888] => // sometimes empty
    [newPrice88888] =>
    [usedQuantity88888] => 4
    [usedPrice88888] => 12.00
    [total88888] => 48.00
    [newQuantity44444] => 2
    [newPrice44444] => 4.00
    [usedQuantity44444] => 0
    [usedPrice44444] => 3.99
    [total44444] => 8.00 // these values I don't need
    [date] => July 25 2021 // these values below I don't need
    [address] => 123 Anystreet Avenue
    [address2] =>
    [zipcode] => 90210
    [city] => Beverly Hills
    [state] => CA
    [planet] => Mars
)

I've been trying to use that array to create a special "sub-array" for only the SKU numbers and just their new and used quantities and prices.

DESIRED RESULT:

Array
(
    [77777] => Array
        (
            [newQuantity] => 3
            [newPrice] => 5.00
            [usedQuantity] => 1
            [usedPrice] => 3.99
        )

    [88888] => Array
        (
            [newQuantity] => 0
            [newPrice] => 0
            [usedQuantity] => 4
            [usedPrice] => 12.00
        )

    [44444] => Array
        (
            [newQuantity] => 2
            [newPrice] => 4.00
            [usedQuantity] => 0
            [usedPrice] => 3.99
        )

)

Knowing that my SKU numbers are always exactly 5 digits, and no other $_POST keys will ever have 5 digits, I've been able to accomplish this with horribly convoluted and unsatisfactory code like this:

$sku = array();
foreach($_POST as $var => $val) {
$number = substr($var,-5);
if (preg_match("/\d{5}/",$sku)) {
$sku[$number] = // the array keys will be the SKU numbers
// then I keep looping to look for the string "newQuantity"
// capture that value... and create little mini arrays
// for my big multidimensional array.....

Is there a better way to go about this?

Thank you.