Variable calculations

[Texan78]

Hello, I am trying to take the calculations of two variables to create a new data for a new variable. For example.....

 

LRH_calcLevel($LRH_current, $LRH_bankfull); +/- $LRH_totalDepth = $newVar 

 

Which should translate to -10.43 Ft +/- 40 = $newVar (-29.57) <----- What I want

 

Instead it is showing up as 10.43 Ft +/- 40 = $newVar (-50.43) <----- How it is displaying which is incorrect

 

Here is the code I am using. The second function is what I am trying to use to create the new variable data based on the calculations above from the data provide via XML. How can I get this to display correctly?

 

-Thanks

//Parse Lake Ray Hubbard XML Data
$site = simplexml_load_file($LRH_data);{

        $LRH_bankfull   = '435.5';
        $LRH_totalDepth = '40';
        $LRH_current    = $site->observed->datum[0]->primary;
        $LRH_vaild      = $site->observed->datum[0]->valid;
        $LRH_updated    = DATE("D, M d, g:i a", STRTOTIME($LRH_vaild));

}

//Lets calculate the lake depatures from full pool for Lake Ray Hubbard
function LRH_calcLevel($LRH_current, $LRH_bankfull)
{
    //Get float values from strings
    $LRH_current = floatval($LRH_current);
    $LRH_bankfull = floatval($LRH_bankfull);
    //Calculate the difference
    $LRH_calcLevel = $LRH_current - $LRH_bankfull;
    //Format difference to two decimal places and add 'Ft'
    $LRH_calcLevelStr = (string) number_format($LRH_calcLevel, 2) . ' Ft';
    //If vlaue is positive add a + to beginning
    if($LRH_calcLevel>0) { $LRH_calcLevelStr = '+'.$LRH_calcLevelStr; }
    //Return the calculated formatted value
    return $LRH_calcLevelStr;
}

////Lets calculate the lake percentage from full pool for Lake Ray Hubbard
$val1 = $LRH_current;
$val2 = $LRH_bankfull;

$LRH_prec = ( $val1 / $val2) * 100;

// 1 digit after the decimal point
$LRH_prec = round($LRH_prec, 1);

//Lets convert the depature from full pool for Lake Ray Hubbard
function LRH_calcDepth($LRH_calcLevelStr, $LRH_totalDepth)
{
    //Get float values from strings
    $LRH_calcDepthStr = floatval($LRH_calcLevelStr);
    $LRH_totalDepth = floatval($LRH_totalDepth);
    //Calculate the difference
    $LRH_calcDepth = $LRH_calcDepthStr - $LRH_totalDepth;
    //Format difference to two decimal places and add 'Ft'
    $LRH_calcDepthStr = (string) number_format($LRH_calcDepth, 2) . ' Ft';
    //If vlaue is positive add a + to beginning
    if($LRH_calcDepth>0) { $LRH_calcDepthStr = '+'.$LRH_calcDepthStr; }
    //Return the calculated formatted value
    return $LRH_calcDepthStr;
}

////Lets calculate the lake percentage from full pool for Lake Ray Hubbard
$val1 = LRH_calcLevel($LRH_current, $LRH_bankfull);
$val2 = $LRH_totalDepth;

[Texan78]

I got it sorted. 

//Lets convert the full pool current to actual current depth
$LRH_calcTotalDepth = $LRH_totalDepth;
$LRH_calcDepart = LRH_calcLevel($LRH_current, $LRH_bankfull);
$LRH_currentTotal = $LRH_calcTotalDepth + $LRH_calcDepart;