perplexing issue with some calculations

sarah31 · 07-11-2004, 02:35 PM

i have this code:

Code:

	$_POST['quantity'] = 0;
	for ($i=0;$i<30;$i++){
		$_POST['quantity'] += $_POST['q'.$i];
	}
	print "<div class='center-text'><b>Number of Books:</b> {$_POST['quantity']}</div>";

	$_POST['fmvtotal'] = 0;
	for ($i=0;$i<30;$i++){
		$_POST['fmvtotal'] += $_POST['fmv'.$i];
	}
	$_POST['fmvtotal'] = number_format ($_POST['fmvtotal'], 2);
	print "<div class='center-text'><b>FMV Total $:</b> {$_POST['fmvtotal']}</div>"; 

	if ($_POST['fmvtotal'] >= 1 && $_POST['fmvtotal'] <= 100) {
	$_POST['ins'] = '3.50';
	} elseif ($_POST['fmvtotal'] > 100) {
	$_POST['ins'] = (ceil(($_POST['fmvtotal'] - 100) / 100) * 0.45) + 3.50;
	} else {
	$_POST['ins'] = 0;
	}
	
	$_POST['ins'] = number_format ($_POST['ins'], 2);
	print "<div class='center-text'><b>Insurance Total $:</b> {$_POST['ins']}</div>"; 
	
	

	$_POST['servicesubtotal'] = $_POST['service']*$_POST['quantity'];
	
	$_POST['servicesubtotal'] = number_format ($_POST['servicesubtotal'], 2);
	print "<div class='center-text'><b>Service Charges $:</b> {$_POST['servicesubtotal']}</div>";

	if ($_POST['quantity'] == 1) {
	$_POST['shipping'] = '7.40';
	} elseif ($_POST['quantity'] == 2){
	$_POST['shipping'] = '10.90';
	} elseif ($_POST['quantity'] >= 3 && $_POST['quantity'] <= 5){
	$_POST['shipping'] = '14.90';
	} elseif ($_POST['quantity'] > 5) {
	$_POST['shipping'] = (($_POST['quantity']-5)*1)+14.90;
	} else {
	$_POST['shipping'] = 0;
	}

	$_POST['shipping'] = number_format ($_POST['shipping'], 2);
	print "<div class='center-text'><b>Shipping Cost:</b> {$_POST['shipping']}</div><br>";

	//grand total calculation

	$_POST['grandtotal'] = $_POST['shipping']+$_POST['servicesubtotal']+$_POST['ins'];
	$_POST['grandtotal'] = number_format ($_POST['grandtotal'], 2);
	print "<div class='center-text'><b>GRAND TOTAL$:</b> {$_POST['grandtotal']}</div>";

now if i have the following numbers entered:

Code:

Quantity 90
Publisher DC
Title Wonder Woman
Issue # 105
Month/Year June 1958
FMV 11250

i get this output:

Code:

Number of Books: 90
FMV Total $: 11,250.00
Insurance Total $: 3.50
Service Charges $: 1,260.00
Shipping Cost: 99.90

GRAND TOTAL$: 104.40

obviously the insurance (ins) calculation is not accepting the FMV Total number into the calculation and the shipping total is not being allowed into the grand total either. i have looked and look for an answer but i haven't found any explanation and i need this fixed.

sde · 07-11-2004, 05:08 PM

number_format returns a string. the problem is when it adds a ',' in the number, php doesn't know how to cast it back and handle it as a float.

if you converted 11,250.00 to a float, it drops everything off past the first ',', resulting in 11.

i just made those seperate variables since you are just doing that to print to the screen.

PHP Code:


			
    for ($i=0;$i<30;$i++){

        $quantity += $_POST['q'.$i];

    }    

    print "<div class='center-text'><b>Number of Books:</b> ".$quantity."</div>";



    for ($i=0;$i<30;$i++){

        $fmvtotal += $_POST['fmv'.$i];

    }

    

    $fmvtotal_string = number_format($fmvtotal, 2);    

    print "<div class='center-text'><b>FMV Total $:</b> ".$fmvtotal_string."</div>"; 



    if ($fmvtotal >= 1 && $fmvtotal <= 100) {

      $ins = 3.50;

    } elseif ($fmvtotal > 100.0) {

      $ins = ( ceil( ( $fmvtotal - 100) / 100 ) * 0.45) + 3.50;

    } else {

      $ins = 0;

    }

    

    $ins_string = number_format($ins, 2);

    print "<div class='center-text'><b>Insurance Total $:</b> ".$ins_string."</div>"; 

    

    $servicesubtotal = $_POST['service'] * $quantity;

    

    $servicesubtotal = number_format($servicesubtotal, 2);

    print "<div class='center-text'><b>Service Charges $: </b>".$servicesubtotal."</div>";



    if ($quantity == 1) {

      $shipping = '7.40';

    } elseif ($quantity == 2){

      $shipping = '10.90';

    } elseif ($quantity >= 3 && $_POST['quantity'] <= 5){

      $shipping = '14.90';

    } elseif ($quantity > 5) {

      $shipping = (($quantity-5)*1)+14.90;

    } else {

      $shipping = 0;

    }



    $shipping_string = number_format($shipping, 2);

    print "<div class='center-text'><b>Shipping Cost:</b> ".$shipping_string."</div><br>";



    //grand total calculation

    $grandtotal =  $shipping+$servicesubtotal+$ins;

    $grandtotal = number_format($grandtotal, 2);

    print "<div class='center-text'><b>GRAND TOTAL$:</b> ".$grandtotal."</div>";

also, notice you don't need the $_POST[] for every variable. you should really only need to use $_POST[] when retrieving values from a form whos method is set to POST.

sarah31 · 07-11-2004, 07:11 PM

hmmm...does it matter that there is no way of telling if someone will be submitting values over three digits in length? the 90 and 11250 were just examples for this question but in actuality the chances that those exact numbers will be entered is slim.

as for not using $_POST[] would that not require register globals to be on? my understanding is that register globals is not something you really want on for security reasons.

EDIT: oh and btw the data that the calculations are being performed on are from a form.

sde · 07-11-2004, 08:31 PM

i understand those were just examples. my fix will handle any value as it handles those examples.

2. register_globals just won't let you access POST form data without the $_POST[] array defined. it is perfectly fine to not use $_POST[] if you are creating new variables in your script.

3. it should work fine. just the 'dummy vars' at the top out and it should work with the form data.

have you tried it?

sarah31 · 07-11-2004, 08:39 PM

not yet. i just wanted to be sure of the dummay variables and such first. thanks for the help i will apply your suggested changes tomorrow ... i am too tired right now.

sde · 07-11-2004, 08:53 PM

there, i took them out to avoid confusion

.. it is just how i was testing the script.

sarah31 · 07-11-2004, 09:29 PM

heh. thanks. as always i appreciate the help.

sde · 07-12-2004, 06:04 AM

omg! i did this before i went to sleep and i had a dream that i was wrong about using new variables without $_POST[] hahah .. it was generating errors .. but it was just a dream.

sarah31 · 07-12-2004, 09:10 AM

could be worse you could have dreamed you were being persued by man-eating anteaters. just when you thought you would be safe one of their long skinny tongues wraps around your ankle tripping you. you can guess the rest.

sde · 07-12-2004, 09:43 AM