Calculate total and percent of total - poll script

hbradshaw

Hello:

I received help from Thomas (tsinka) earlier with a poll script which works beautifully.

Now, I'm taking one step further and I'm trying to calculate the percent of total votes cast by row.

There are 6 rows or colors. Total votes cast is 41.

The result of my script currently gives me the following table:

Color    Vote Cast    Total ($total var)   Percent ($percent var)
green       8                        8                      100
blue         3                      11                       27
yellow      7                      18                    38.9
pink         8                       26                   30.8
red          9                       35                   25.7
purple     6                       41                   14.6

The results of the script are wrong especially the percent calculation.

The way the script is written I understand what it's doing. I just don't know how to fix it.

=====================================

The script should do the following calculations:
a.) grand total of the vote cast column
b.) percentage of vote cast / grand total for each color

The correct table result from this script should look like:

Color    Vote Cast     Percent 
green       8                   19.5
blue         3                     7.3
yellow      7                   17.1
pink         8                   19.5
red          9                   22.0
purple     6                   14.6

Total       41                  100.0%

Can someone help me figure out how to properly perform these calculations and show me what I was doing wrong?

Thank you so very much........

Here is the script:

<?php

//connect to server and select database
$conn = mysql_connect("mysql.addr.com", "summitweb", "summitdb") or die(mysql_error());
mysql_select_db("summitweb",$conn) or die(mysql_error());

if (isset($POST['color']) && !empty($POST['color']))
mysql_query("UPDATE color SET tally=tally+1 WHERE name='{$_POST['color']}'");

$result = mysql_query("SELECT name, tally FROM color") or die(mysql_error());

$num_rows = mysql_num_rows($result);

?>
<html>
<head>
<meta http-equiv="Content-Language" content="en-us">

<title></title>
<link href="style.css" rel="stylesheet" type="text/css">
</head>
<body>
Number of colors: <?PHP echo $num_rows; ?>
<table width="457" border="1">
<tr>
<td width="50">Color</td>
<td width="50">Tally (Actual votes cast)</td>
<td width="50">Total ($total variable)</td>
<td width="50">Percent ($percent variable)</td>
</tr>
<?PHP
$total=0;
while ($row = mysql_fetch_array($result)) {
$total+=$row['tally'];
$percent=(100 * $row['tally']) / $total;
?>
<tr>

drawmack

<?php
//connect to server and select database
$conn = mysql_connect("localhost", "username", "password") or die(mysql_error());
mysql_select_db("database",$conn)  or die(mysql_error());

if (isset($_POST['color']) && !empty($_POST['color'])) 
    mysql_query("UPDATE color SET tally=tally+1 WHERE name='{$_POST['color']}'"); 

//we're going to get the total here
$sql = "SELECT SUM(tally) FROM color";
$total = mysql_result(mysql_query($sql);

$result = mysql_query("SELECT name, tally FROM color") or die(mysql_error()); 

$num_rows = mysql_num_rows($result);

?> 
<html> 
<head> 
<meta http-equiv="Content-Language" content="en-us"> 

<title></title> 
<link href="style.css" rel="stylesheet" type="text/css"> 
</head> 
<body> 
<font size="2" face="Verdana">Number of colors: <?PHP echo $num_rows; ?></font> 
<table width="457" border="1">
<tr>
<td width="50">Color</td>
    <td width="50">Tally (Actual votes cast)</td>
    <td width="50">Total ($total variable)</td>
    <td width="50">Percent ($percent variable)</td>
</tr> 
<?PHP 
$total=0;
while ($row = mysql_fetch_array($result)) {
    //your praenthesis were wrong here, I fixed that and
    //rounded the results
    $percent=round((100*($row['tally']/$total)),2); 
?> 
<tr>  

<td width="50"> 
<font size="2" face="Verdana"><?PHP echo $row['name']; ?></font> 
</td> 
<td width="50"> 
<font size="2" face="Verdana"><?PHP echo $row['tally']; ?></font> 
</td>  

<td width="50"> 
<font size="2" face="Verdana"><?PHP echo $total; ?></font> 
</td> 
<td width="50"> 
<font size="2" face="Verdana"><?PHP echo $percent; ?></font> 
</td> 
</tr> 
<?PHP 
}  //end while
?>

hbradshaw

Hi,

Thank you for the reply. I made the modifcations as you suggested and I'm receiving quite a few error messages.

=========================

Here are the messages:

Warning: Wrong parameter count for mysql_result() in /usr50/home/summitwe/public_html/poll.php on line 13

Number of colors: 6 Color Tally (Actual votes cast) Total ($total variable) Percent ($percent variable)

Warning: Division by zero in /usr50/home/summitwe/public_html/poll.php on line 42
green 8 0 0

Warning: Division by zero in /usr50/home/summitwe/public_html/poll.php on line 42
blue 4 0 0

Warning: Division by zero in /usr50/home/summitwe/public_html/poll.php on line 42
yellow 8 0 0

Warning: Division by zero in /usr50/home/summitwe/public_html/poll.php on line 42
pink 8 0 0

Warning: Division by zero in /usr50/home/summitwe/public_html/poll.php on line 42
red 9 0 0

Warning: Division by zero in /usr50/home/summitwe/public_html/poll.php on line 42
purple 6 0 0

I'm not quite sure what to do with these messages. Can you help me out?

Thank you in advance.

==========================
Here is the modified script:

<?php

//connect to server and select database
$conn = mysql_connect("mysql.addr.com", "summitweb", "summitdb") or die(mysql_error());
mysql_select_db("summitweb",$conn) or die(mysql_error());

if (isset($POST['color']) && !empty($POST['color']))
mysql_query("UPDATE color SET tally=tally+1 WHERE name='{$_POST['color']}'");

//we're going to get the total here
$sql = "SELECT SUM(tally) FROM color";
$total = mysql_result(mysql_query($sql));

$result = mysql_query("SELECT name, tally FROM color") or die(mysql_error());

$num_rows = mysql_num_rows($result);

$percent=round((100*($row['tally']/$total)),2);
?>

<tr>

drawmack

ooppss change this line

<?php $total = mysql_result(mysql_query($sql));

<?php $total = mysql_result(mysql_query($sql),0,0);

Next time you receive a parameter count wanrning try typing http://www.php.net/functionName (i.e. http://www.php.net/mysql_result) into your browser.

hbradshaw

Hello:

Thank you for responding.

I modified the line as you suggested. I ran the script and I received warnings about a division by 0.

Here are the warnings that were generated:

Number of colors: 6 Color Tally (Actual votes cast) Total ($total variable) Percent ($percent variable)

Warning: Division by zero in /usr50/home/summitwe/public_html/poll.php on line 42
green 8 0 0

Warning: Division by zero in /usr50/home/summitwe/public_html/poll.php on line 42
blue 4 0 0

Warning: Division by zero in /usr50/home/summitwe/public_html/poll.php on line 42
yellow 9 0 0

Warning: Division by zero in /usr50/home/summitwe/public_html/poll.php on line 42
pink 8 0 0

Warning: Division by zero in /usr50/home/summitwe/public_html/poll.php on line 42
red 9 0 0

Warning: Division by zero in /usr50/home/summitwe/public_html/poll.php on line 42
purple 6 0 0

====================
My feeling is that the $total variable that is defined in the begining of the script is not being passed to the $percent calculation within the while structure.

I'm not quite sure how to fix this. I'm new to PHP and so far I haven't even attempted to write a script that uses two SELECT queries where info from one query is passed to the second query.

Can you help me?

Thank you so much for your time.

=================
Here's the script:

<?php

//connect to server and select database
$conn = mysql_connect("mysql.addr.com", "summitweb", "summitdb") or die(mysql_error());
mysql_select_db("summitweb",$conn) or die(mysql_error());

if (isset($POST['color']) && !empty($POST['color']))
mysql_query("UPDATE color SET tally=tally+1 WHERE name='{$_POST['color']}'");

//we're going to get the total here
$sql = "SELECT SUM(tally) FROM color";
$total = mysql_result(mysql_query($sql),0,0);

$result = mysql_query("SELECT name, tally FROM color") or die(mysql_error());

$num_rows = mysql_num_rows($result);

$percent=round((100*($row['tally']/$total)),2);
?>

<tr>