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Math unable to account for 1000??

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Join Date: Apr 2009

Posts: 24

Reputation: kssi89 is an unknown quantity at this point

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kssi89

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Newbie Poster

Math unable to account for 1000??

May 1st, 2009

This was mentioned in a previous thread but I am thinking this problem may warrant a new one. The code I am working with here:

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<?php
//connect to the database
$connect = mysql_connect("localhost", "root", "password") or
    die ("Hey loser, check your server connection.");
 
mysql_select_db("ecommerce");
?>
<html>
    <head>
        <title>Here is Your Shopping Cart!</title>
        </head>
    <body>
        <dev align="center">
            You currently have
 
            <?php
            $sessid = session_id();
 
            //display number of products in cart
            $query = "SELECT * FROM carttemp WHERE carttemp_sess = '$sessid'";
            $results = mysql_query($query)
                or die (mysql_query());
            $rows = mysql_num_rows($results);
            echo $rows;
            ?>
 
            product(s) in your cart.<br>
 
            <table border="1" align="center" cellpadding="5">
                <tr>
                    <td>Quantity</td>
                    <td>Item Image</td>
                    <td>Item Name</td>
                    <td>Price Each</td>
                    <td>Extended Price</td>
                    <td></td>
                    <td></td>
                <?php
                $total = "0";
 
                    echo"<tr>";
                while ($row = mysql_fetch_array($results)) {
                extract($row);
                $prod = "SELECT * FROM products " .
                        "WHERE products_prodnum='$carttemp_prodnum'";
                $prod2 = mysql_query($prod);
                $prod3 = mysql_fetch_array($prod2);
                extract ($prod3);
                echo "<td>
                        <form method=\"POST\" action=\"modcart.php?action=change\">
                        <input type=\"hidden\" name=\"modified_hidden\"
                            value=\"$carttemp_hidden\">
                        <input type=\"text\" name=\"modified_quan\" size=\"2\"
                            value=\"$carttemp_quan\">";
                echo "</td>";
                echo "<td>";
                echo "<a href=\"getprod.php?prodid=" . $products_prodnum . "\">";
                echo "THUMBNAIL<br>IMAGE</a></td>";
                echo "<td>";
                echo "<a href=\"getprod.php?prodid=" . $products_prodnum . "\">";
                echo $products_name;
                echo "</a></td>";
                echo "<td align=\"right\">";
                //changed to number format instead of just var april 29 2009
                echo number_format($products_price, 2);
                echo "</td>";
                echo "<td align=\"right\">";
                //get extended price
                $extprice = number_format($products_price * $carttemp_quan, 2);
                echo $extprice;
                echo "</td>";
                echo "<td>";
                echo "<input type=\"submit\" name=\"Submit\"
                        value=\"Change Qty\">
                    </form></td>";
                echo "<td>";
                echo "<form method=\"POST\" action=\"modcart.php?action=delete\">
                <input type=\"hidden\" align=\"center\" name=\"modified_hidden\"
                    value=\"$carttemp_hidden\">";
                echo "<input type=\"submit\" name=\"Submit\"
                    value=\"Delete Item\">
                </form></td>";
                echo "</tr>";
                //add extended price to total
                $total = $extprice + $total;
 
                }
                ?>
                    <tr>
                        <td colspan=\"4\" align=\"right\">
                            Your total before shipping is:</td>
                        <td align=\"right\"> <?php echo number_format($total, 2); echo "@ $total"; ?></td>
                        <td></td>
                        <td>
                    <?php // removed space from value below
                    echo "<form method=\"POST\" action=\"modcart.php?action=empty\">
                            <input type=\"hidden\" name=\"carttemp_hidden\
                                value=\"";
                    if (isset($carttemp_hidden)) {
                        echo $carttemp_hidden;
                    }
 
                    echo "\">";
                    echo "<input type=\"submit\" name=\"Submit\" value=\"Empty Cart\">
                        </form>";
                    ?>
 
                    </tr>
                        </table>
            <form method="POST" action="checkout.php">
                <input type="submit" name="Submit" value="Proceed to Checkout">
                    </form>
            <a href="shop.php">Go back to the main page</a>
            </div>
        </body>
        </html>
<?php
//connect to the database
$connect = mysql_connect("localhost", "root", "password") or
    die ("Hey loser, check your server connection.");

mysql_select_db("ecommerce");
?>
<html>
    <head>
        <title>Here is Your Shopping Cart!</title>
        </head>
    <body>
        <dev align="center">
            You currently have
            
            <?php
            $sessid = session_id();
            
            //display number of products in cart
            $query = "SELECT * FROM carttemp WHERE carttemp_sess = '$sessid'";
            $results = mysql_query($query)
                or die (mysql_query());
            $rows = mysql_num_rows($results);
            echo $rows;
            ?>
            
            product(s) in your cart.<br>
            
            <table border="1" align="center" cellpadding="5">
                <tr>
                    <td>Quantity</td>
                    <td>Item Image</td>
                    <td>Item Name</td>
                    <td>Price Each</td>
                    <td>Extended Price</td>
                    <td></td>
                    <td></td>
                <?php
                $total = "0";

                    echo"<tr>";
                while ($row = mysql_fetch_array($results)) {
                extract($row);
                $prod = "SELECT * FROM products " .
                        "WHERE products_prodnum='$carttemp_prodnum'";
                $prod2 = mysql_query($prod);
                $prod3 = mysql_fetch_array($prod2);
                extract ($prod3);
                echo "<td>
                        <form method=\"POST\" action=\"modcart.php?action=change\">
                        <input type=\"hidden\" name=\"modified_hidden\"
                            value=\"$carttemp_hidden\">
                        <input type=\"text\" name=\"modified_quan\" size=\"2\"
                            value=\"$carttemp_quan\">";
                echo "</td>";
                echo "<td>";
                echo "<a href=\"getprod.php?prodid=" . $products_prodnum . "\">";
                echo "THUMBNAIL<br>IMAGE</a></td>";
                echo "<td>";
                echo "<a href=\"getprod.php?prodid=" . $products_prodnum . "\">";
                echo $products_name;
                echo "</a></td>";
                echo "<td align=\"right\">";
                //changed to number format instead of just var april 29 2009
                echo number_format($products_price, 2);
                echo "</td>";
                echo "<td align=\"right\">";
                //get extended price
                $extprice = number_format($products_price * $carttemp_quan, 2);
                echo $extprice;
                echo "</td>";
                echo "<td>";
                echo "<input type=\"submit\" name=\"Submit\"
                        value=\"Change Qty\">
                    </form></td>";
                echo "<td>";
                echo "<form method=\"POST\" action=\"modcart.php?action=delete\">
                <input type=\"hidden\" align=\"center\" name=\"modified_hidden\"
                    value=\"$carttemp_hidden\">";
                echo "<input type=\"submit\" name=\"Submit\"
                    value=\"Delete Item\">
                </form></td>";
                echo "</tr>";
                //add extended price to total
                $total = $extprice + $total;
                
                }
                ?>
                    <tr>
                        <td colspan=\"4\" align=\"right\">
                            Your total before shipping is:</td>
                        <td align=\"right\"> <?php echo number_format($total, 2); echo "@ $total"; ?></td>
                        <td></td>
                        <td>
                    <?php // removed space from value below
                    echo "<form method=\"POST\" action=\"modcart.php?action=empty\">
                            <input type=\"hidden\" name=\"carttemp_hidden\
                                value=\"";
                    if (isset($carttemp_hidden)) {
                        echo $carttemp_hidden;
                    }
                    
                    echo "\">";
                    echo "<input type=\"submit\" name=\"Submit\" value=\"Empty Cart\">
                        </form>";
                    ?>
                    
                    </tr>
                        </table>
            <form method="POST" action="checkout.php">
                <input type="submit" name="Submit" value="Proceed to Checkout">
                    </form>
            <a href="shop.php">Go back to the main page</a>
            </div>
        </body>
        </html>

The $total can account for items written like this:

item 1 - $900.00
(table row)
item 1 - $900.00
(table row)
total - 1800.00

item 2 - $50.00 x19 - ExtPrice: 950.00
total - 950.00

But not like this:

item 1 - $900.00 x2 - ExtPrice: 1800.00
total = 1.00

item 1 - $900.00 x3 - ExtPrice: 2700.00
total = 2.00

---

I am about at the end of my rope with this, do you php gurus have any suggestions?

Last edited by kssi89; May 1st, 2009 at 10:58 am.

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Join Date: Aug 2007

Posts: 169

Reputation: Fest3er is an unknown quantity at this point

Solved Threads: 19

Fest3er

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Junior Poster

Re: Math unable to account for 1000??

May 1st, 2009

May I suggest keeping all numbers as true numbers? Only convert them to formatted strings when you display them to the user. You might be mixing numbers and strings in your arithmetic operations--strings don't always convert nicely to numbers.

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Join Date: Oct 2006

Posts: 1,558

Reputation: ardav will become famous soon enough

Solved Threads: 206

ardav

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Anthrax Poster

Re: Math unable to account for 1000??

May 1st, 2009

Second that. The numbers returned for $total seem to be from the first non-zero 'integer' part of the price. Keep prices as float datatype in your DB. I assume you have it as varchar to include the '$'? If so, I think php is struggling to understand the 'price' variable as a float.

Hold on, just though of something - does it happen when you have a price of below $100 with a multiplier of >10 (to force a total of >$1000)? If not, your problem is definitely the price (and possibly the use of numberformat with it).

Last edited by ardav; May 1st, 2009 at 5:52 pm. Reason: made a boob

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Join Date: Jan 2009

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Reputation: almostbob is a jewel in the rough

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almostbob

Online

Posting Virtuoso

Re: Math unable to account for 1000??

May 1st, 2009

[Rant = Slightly off topic, My favorite Subject]

simplify the database
change any text dates "October 15 2008"(smalltext 15 characters) etc to timestamps
strip out the $signs
you only need them when you print out information
echo '$ '.$extPrice; is just as fast and causes no $_ errors
the database should contain
no formatting
no text dates or times
nothing but data in its simplest form,
its easier to manipulate, smaller, faster, cheaper to maintain
and you can calculate on the fields, which is more difficult to do with text representations,
not so much now for 50 items, 50Bytes extra per row isnt much
but when the db grows to 500 000 items and there are millions of transactions in the transaction table, 50Bytes per row is a lot

[/Rant]

Last edited by almostbob; May 1st, 2009 at 10:26 pm.

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