fluctuation

[grlayouts]

say i have a record that changes from 1 - 10000

 

and i want it to create a price between 25-300 depending on how many there are.

 

ie 5000 price is 300

 

any idea's?

[revraz]

You need to have a formula first.

[grlayouts]

well i've had a few( one posted yesterday) i was thinking an algorithm but i never wrote one.

[boushley]

Its really not very hard to write one... 1=25 & 10000=300...

so you've got a difference of 9,999 and 275.

So, it would be something like price=25+(num*(275/9999))

And then can you do it from there?

[Barand]

You could allocate on a straight line. If qty is 10000, price is 25 each, if 1 then 300 each

[pre]

  300+  \

    |  \

    |    \

  150+    .\

    |    . \

    |    .  \

  25+    .  \

        +-+----+--

      1  .    10000

          .

          2000 = 245

         

          P = -275 * Q  + 300

              --------

                10000

[/pre]

 

<?php
function price ($q)
{
    
    return ceil($q * -275 / 10000) + 300;
}

for ($i = 0; $i <= 10000; $i+=1000) 
{
    $q = $i==0 ? 1 : $i;
    echo "$q :" . price($q) . '<br>';
}  

-->
1      :300
1000 :273
2000 :245
3000 :218
4000 :190
5000 :163
6000 :135
7000 :108
8000 :80
9000 :53
10000 :25

[grlayouts]

barand thats exactly what i was looking for. will it work if the quantitys are 333? or 659?

[Barand]

Any value from 1 to 10000.

 

If it's 20,000 you pay them 250 to take them away

 

 

try it!

 

<?php
function price ($q)
{
    
    return ceil($q * -275 / 10000) + 300;
}

$qtys = array(1, 333, 659, 1000, 5000, 10000);
foreach ($qtys as $q) 
{
    echo "$q :" . price($q) . '<br>';
}  

/*
-->
1 :300
333 :291
659 :282
1000 :273
5000 :163
10000 :25
*/
?>

[grlayouts]

do i have to set $q? as my product ammount?

$q = mysql_fetch_row(mysql_query("SELECT SUM(product) FROM players;"));

[grlayouts]

Barand i can't thank you enough mate.. thanks for the help i ended up with

<?
include('config.php');
$q2 = mysql_fetch_row(mysql_query("SELECT SUM(drugs) FROM players;"));
function price ($q)
{
    
    return ceil($q * -275 / 20000) + 300;
}

$qtys = $q2;
foreach ($qtys as $q) 
{
    echo "$q :" . price($q) . '<br>';
}  
mysql_query('UPDATE players SET drugs = drugs + (drugfact*20), dpayout = (drugfact*20);');
mysql_query('UPDATE players SET credits = credits - (employees*wages)');
$sql = "UPDATE price SET cost = $q where ITEM = 'drugs'";
mysql_query($sql) or
  die($sql . ' : ' . mysql_error());
?>

 

works a treat!!

[Barand]

Any var name you like (meaningful ones are best)

 

<?php
function price ($q)
{
    if ($q > 10000) return 25;
    return ceil($q * -275 / 10000) + 300;
}

$res = mysql_query("SELECT SUM(product) FROM players");
$quantity = mysql_result($res, 0);

echo 'Qty : ' . $quantity . ' at ' . price($quantity) . ' each';

?>
  

[grlayouts]

now if i have 4000 of (product) at price 240 and 3999 are sold instead of it going back up to the max at 300 return maybe 290