picking the lowest value from a series of vars...

SpockBert

I need to populate a "prices from $X" line where X is the lowest value from about 20 different vars loaded from a DB for that ID.

So if say:

$var1 = 25;
$var2 = 40;
$var3 = 10;

and you had something like:

echo "Prices available from as little as $lowValue";

Just wondering if theres a quick simple way to get $lowValue from var1,2 and 3 etc

Simon

drew010

check out the [man]min[/man] function or just add all values to an array, sort it and show the first value.

SpockBert

drew010 wrote:
check out the [man]min[/man] function or just add all values to an array, sort it and show the first value.

Thanks mate, that min function looks just the thing, knew they'd be something simple 🙂

SpockBert

I seem to have run into a problem with this regarding blank or undefined values.

$var1 = 34;
$var2 = 23;
$var3 = 17;

$lowPrice = min($var1,$var2,$var3);
echo "low price = $lowPrice";

returns "low price = 17", no problems there but what if one or more of the values is blank or undefined?

$var1 = 34;
$var2 = 23;
$var3 = "";

$lowPrice = min($var1,$var2,$var3);
echo "low price = $lowPrice";

will return "low price ="

Is there anyway you can get this Min() function to return the first you know proper number and not some blank/undefined or zero number? In other words how would I get that last example to return "low price = 23"

drew010

thats how its programmed to work but you can manually use [man]empty[/man] and/or [man]isset[/man] to make sure the variable is proper.

xxdrossxx

try defining your own function to screen the values before comparing them, so none of your empty variables will get through to the 'min' function. like so:

<?php
function safeMin()  {
  $nums = array();
  for ($i = 0; $i < func_num_args(); $i++)
    if (func_get_arg($i))
      $nums[] = func_get_arg($i);
  return min($nums);
}

$var1 = 34;
$var2 = 17;
$var3 = "";
$var4 = 23;

$lowPrice = safeMin($var1, $var2, $var3, $var4);
echo "low price = $lowPrice";
?>

the output of that code will be "low price = 17". make sense?

SpockBert

xxdrossxx wrote:
try defining your own function to screen the values before comparing them, so none of your empty variables will get through to the 'min' function. like so:
<?php
function safeMin()  {
  $nums = array();
  for ($i = 0; $i < func_num_args(); $i++)
    if (func_get_arg($i))
      $nums[] = func_get_arg($i);
  return min($nums);
}

$var1 = 34;
$var2 = 17;
$var3 = "";
$var4 = 23;

$lowPrice = safeMin($var1, $var2, $var3, $var4);
echo "low price = $lowPrice";
?>
the output of that code will be "low price = 17". make sense?

Thanks mate, I'll try that looks good.

I was gonna go with a real ugly workaround where if a var was empty I'd give it a value of '999999' to send it to the back of the queue! Then do the min() to get my value for $lowPrice then reset any changed vars back to 0!

I like your method better though 😉