PHP - Calculation Problem In Php

Hi,

I have a calculation issue in my php. Below is my code:

Code: [Select]
$output = "";
$studentId  = false;
$courseId  = false;
$moduleId  = false;
       
while ($row = mysql_fetch_array($result)){   

        $moduletotal += $row['Mark'];
       
        $modulemark = (int)($moduletotal);
         
//Above here is the calculation for add in the Marks of all the sessions

//Below is the code of the display of the query output


if($studentId != $row['StudentUsername'])  {       

$studentId = $row['StudentUsername'];       
$output .= "<p><strong>Student:</strong> {$row['StudentForename']} {$row['StudentSurname']} ({$row['StudentUsername']})";   

   }   
   
    if($courseId != $row['CourseId']) {   

$courseId = $row['CourseId'];       
$output .= "<br><strong>Course:</strong> {$row['CourseId']} - {$row['CourseName']} <br><strong>Year:</strong> {$row['Year']}</p>";   

}   

if($moduleId != $row['ModuleId'])  {       

   $moduleId = $row['ModuleId'];       
   $output .= "<p><br><strong>Module:</strong> {$row['ModuleId']} - {$row['ModuleName']} $modulemark</p>";   

  } 
   
   $output .= "<p><strong>Session:</strong> {$row['SessionId']} {$row['Mark']}</p>";
   
  }


Student: Mayur Patel (u0867587)
Course: INFO101 - Bsc Information Communication Technology 
Year: 3


Module: CHI2550 - Modern Database Applications 72 (72 is the answer to the calculation for the first module but this is incorrect at it should also add the 67 and thus become 139)

Session: AAB 72

Session: AAE 67

Module: CHI2513 - Systems Strategy 200 (200 is the answer to the calculation for this module but this is incorrect it should be only 61. But what it has done is that it has added the 72 and 67 from the first module and added it with the 61 in this module)

Session: AAD 61



SO WHAT MY QUESTION IS THAT HOW CAN I FIND THE TOTAL OF EACH MODULE MARK WHICH THE VARIABLE $modulemark = (int)($moduletotal); IS TRYING TO DO BY ADDING UP ALL THE SESSIONS MARKS WITHIN EACH MODULE.

I HAVE TRIED USING SUM(gr.Mark) in the query and using GROUP BY SessionId, ModuleId, StudentUsername, and CourseId but it ends up not being able to display any records. That is why I want to do the calculation using php rather than SQL.

BELOW IS THE QUERY IF YOU WANT TO SEE IT:

Code: [Select]
$query = "
          SELECT st.CourseId, c.CourseName, st.Year, st.StudentUsername, st.StudentForename, st.StudentSurname,
          s.ModuleId, m.ModuleName, m.Credits, s.SessionId, s.SessionWeight, gr.Mark, gr.Grade
          FROM Course c
          INNER JOIN Student st ON c.CourseId = st.CourseId
          JOIN Grade_Report gr ON st.StudentId = gr.StudentId
          JOIN Session s ON gr.SessionId = s.SessionId
          JOIN Module m ON s.ModuleId = m.ModuleId
          WHERE
          (st.StudentUsername = '".mysql_real_escape_string($studentid)."')
          ORDER BY c.CourseName, st.StudentUsername, m.ModuleName, s.SessionId
          ";

This code was given to me by mjdamato to help display a student and the course that student has take and within that the modules in the course and the sessions in course including module mark and grade and student's session marks and grades. I am very weak on php code as I have only done it once and that was following a php workbook 2 years ago. I am more of a database specialist. Below is the code given to me and you can also download the code from the attachment:

Code: [Select]
<?php

function outputModule($moduleID, $moduleName, $sessionData)    
  
  {        
  
  if(!count($sessionData)) { return false; }        
  
  $markTotal = 0;        
  $markGrade = 0;
  $weightSession = 0;
  $grade = "";
  $sessionsHTML = "";
  
  foreach($sessionData as $session)        {           
  
   $sessionsHTML .= "<p><strong>Session:</strong> {$session['SessionId']} <br><strong>Session Mark:</strong> {$session['Mark']}</strong> <br><strong>Session Weight Contribution</strong> {$session['SessionWeight']}%</p>\n";            
   $markTotal += round($session['Mark'] / 100 * $session['SessionWeight']); 
   $weightSession  += ($session['SessionWeight']);  
   $markGrade = round($markTotal /  $weightSession * 100);
   
if ($markGrade >= 70){
$grade = "A";}      

else if ($markGrade >= 60 && $markGrade <= 69){
$grade = "B";}

else if ($markGrade >= 50 && $markGrade <= 59){
$grade = "C";}

else if ($markGrade >= 40 && $markGrade <= 49){
$grade = "D";}

else if ($markGrade >= 30 && $markGrade <= 39){
$grade = "E";}

else if ($markGrade >= 0 && $markGrade <= 29){
$grade = "F";}
   
   }        
   
   $moduleHTML = "<p><br><strong>Module:</strong> {$moduleID} - {$moduleName} <br><strong>Module Mark:</strong> {$markTotal} <br><strong>Mark Percentage:</strong> {$markGrade} <br><strong>Grade:</strong> {$grade} </p>\n";       
   
    return $moduleHTML . $sessionsHTML;    }    
    
    $output = "";    
    
    $studentId = false;    
    $courseId  = false;    
    $moduleId  = false;    
    
    while ($row = mysql_fetch_array($result))    {               
     
     if($studentId != $row['StudentUsername'])        {            
     
     //Student has changed              
     $studentId = $row['StudentUsername'];                    
     
     $output .= "<p><strong>Student:</strong> {$row['StudentForename']} {$row['StudentSurname']} ({$row['StudentUsername']})\n";          
     
      }        
      
     if($courseId != $row['CourseId'])        {         
      
      //Course has changed           
       $courseId = $row['CourseId'];                    
       
       $output .= "<br><strong>Course:</strong> {$row['CourseId']} - {$row['CourseName']} <strong>Course Mark</strong> <strong>Grade</strong>  <br><strong>Year:</strong> {$row['Year']}</p>\n";           
       
        }      
        
 if($moduleId != $row['ModuleId'])        {            
 
 //Module has changed            
 if(isset($sessionsAry)) //Don't run function for first record           
 
  {              
  
    //Get output for last module and sessions                
    $output .= outputModule($moduleId, $moduleName, $sessionsAry);            }            
    
    //Reset sessions data array and Set values for new module           
    
     $sessionsAry = array();            
     $moduleId    = $row['ModuleId'];         
     $moduleName  = $row['ModuleName'];        }        
     
     //Add session data to array for current module      
     
     $sessionsAry[] = array('SessionId'=>$row['SessionId'], 'Mark'=>$row['Mark'], 'SessionWeight'=>$row['SessionWeight']);    
     
     }    //Get output for last module  
     
      $output .= outputModule($moduleId, $moduleName, $sessionsAry);   
      
       //Display the output    
       echo $output;

      }
  }
    ?>
Below the what this code outputs:


Student: Mayur Patel (u0867587)
Course: INFO101 - Bsc Information Communication Technology       Course Mark
Year: 3


Module: CHI2550 - Modern Database Applications        Module Mark: 41          Mark Percentage: 68            Grade: B

Session: AAB             Session Mark: 72               Session Weight Contribution 20%

Session: AAE             Session Mark: 67               Session Weight Contribution 40%


Module: CHI2513 - Systems Strategy            Module Mark: 31           Mark Percentage: 62            Grade: B

Session: AAD              Session Mark: 61             Session Weight Contribution 50%


If you look above it shows that there is nothing in the Course Mark: section, what Course Mark is suppose to do is total up all the module mark percentages and then divide it by the number of modules. So the calculation will be adding up all the Code: [Select]
$markGrade and dividing it by count Code: [Select]
$ModuleID. In examle above it will be 68 (mark percentage for 1st module) + 62 (mark percentage for 2nd  module) / 2 (number of modules in the course). So the Course Mark should equal 65. 

The problem is that all of the calculations are in the foreach loop but where the course details and where the course marks are going to be placed are in the while loop. So the problem is that if the total Course Mark (lets say we call in $totalCourse) is displayed in the while loop it will provide an undifined index as the calculation will be placed with the other calculations in the foreach loop which is outside the while loop, if I do the calculation with in the while loop, it will only choose the 1st module mark percentage and divdie it by the first module only, this is obviously incorrect as it sohuld try and do this for all modules hence why my calculations are in the foreach loop which does this.

So how will change the code so that the course details can go from the while loop and be placed in the foreach loop so then I can include the calculation in the foreach loop.

Thank You and hopefully you understand it, just read it very carefully to understand it, it is very simple what I want to achieve but I do not know how to do it.

[attachment deleted by admin]

Hi Guys, i am trying to get my head around doing a calculation for the total and getting the discount from each row and display the total. I am using both mySql and php. How do i get the TOTAL BALANCE (this is = total balance - the discount) and the TOTAL PAYMENT DUE (this is = TOTAL CLIENT PAYMENT - TOTAL BALANCE). Please note that the discount settings are different for each row and there are an number of different rows.

The table is as follows:
Code: [Select]
`invoiceID` int(11) NOT NULL AUTO_INCREMENT,
  `USERID` varchar(255) NOT NULL DEFAULT '',
  `CLIENTID` varchar(150) NOT NULL DEFAULT '',
  `amount` decimal(10,2) NOT NULL DEFAULT '0.00',
  `Discount` double(4,2) NOT NULL DEFAULT '0.00'
The page code is as follows:

<?php
$query = "SELECT ID FROM clients WHERE username = '$u'";
$result = mysql_query($query);
if(mysql_num_rows($result))
{
while($row = mysql_fetch_assoc($result)){
$USERID = $row['ID'];
$client = mysql_real_escape_string($_GET['id']);
$query = "SELECT * FROM payment WHERE USERID = '$USERID' AND CLIENTID = '$client'";
$result = mysql_query($query);
$num=mysql_numrows($result);
?>
<table>
<thead><tr>
        <th>Invoice ID</th>
        <th>Discount</th>
        <th>Cost</th>
        <th>Balance</th>
        </tr>
</thead>
<tbody>
<?php
$i=0;
while ($i < $num) {
$invoiceID=mysql_result($result,$i,"invoiceID");
$USERID=mysql_result($result,$i,"USERID");
$CLIENTID=mysql_result($result,$i,"CLIENTID");
$amount=mysql_result($result,$i,"amount");
$Discount=mysql_result($result,$i,"Discount");
$balance = $amount - (($amount/100)*$Discount);
?>
<tr>
<td><?php echo $invoiceID; ?></td>
<td><?php echo $Discount; ?></td>
<td><?php echo $amount; ?></td>
<td><?php echo number_format($balance,2); ?></td>
</tr>
<?php
$i++;
}
}
}
$CLIENTID = mysql_real_escape_string($_GET['id']);
$USERID = mysql_real_escape_string($_GET['USERID']);
$sql = "SELECT SUM(amount) AS TOTALPAYMENT FROM payment WHERE CLIENTID = '".$_GET['id']."' AND USERID = '".$_GET['USERID']."'" ;
$resulte = mysql_query($sql);
mysql_close();
if(mysql_num_rows($resulte))
{
while($row = mysql_fetch_assoc($resulte)){
$amount = $row['amount'];
$Discount = $row['Discount'];
$totalPayment = $row['TOTALPAYMENT'];
$balance = $amount - (($amount/100)*$Discount);
?>
</tbody><tfoot>
<tr><td></td></tr>
</tfoot>
</table>
<table>
<tbody>
<tr>
<td>Total Client Payment:</td>
    <td><?php echo number_format($totalPayment,2); ?></td>
</tr>
<tr>
<td>Total Balance:</td>
    <td><?php echo number_format($balance,2); ?></td>
</tr>
<tr>
<td>Total Payment due:</td>
    <td><?php echo ""; ?></td>
</tr></tbody></table>
<?php
}
}
?>

I forgot to note that the TOTAL BALANCE calculation is not correct. Any help would be appreciated.

Dear All,

I am trying to fetch the sum of a column for current date and subtract a value from the sum for currently selected record. The query i build works fine in MySql but when the same query i placed in php no result it's blank. Below is the query.

 

 <?php
//Calculation for no of paxs.
 $query2=mysqli_query($con,"SELECT SUM(noopaxs-gattl) FROM tblsupvisitor where date(EnterDate) = CURDATE() || gst = 'INH' || gst = 'IN' GROUP BY confno");
$calc_no_paxs_for_today=mysqli_fetch_row($query2);
$gattl=$calc_no_paxs_for_today['gattl'];
 ?> 

 

and her is the assignment to the textbox.

 

				<div class="row form-group">
                               <div class="col col-md-3">
                               <label for="textarea-input" style="color: purple" class=" form-control-label"><strong>Total No. Of Adults</strong></label>
                                                </div>

                                                <div class="col-12 col-md-9">
                                                    <input name="gattl" id="gattl" rows="9" class="form-control" required="" value="<?php  echo $gattl;?>">

                                                </div>
                                                </div>

 

Any help in this regard will be highly appreciated.

 

Kind Regards,

Naveed.

This is a bit of a puzzle. Look at the sum and result below:

Code: [Select]
$markTotal += ($session['Mark'] / 100 * $session['SessionWeight']);
Result on Browser

Module: CHI2550 - Modern Database Applications     41.2 (this is $markTotal)

Session: AAB        72(this is $session['Mark'])      20% (this is  $session['SessionWeight'])  (The percentage signs are just add ons)

Session: AAE        67(this is $session['Mark'])      40%  (this is  $session['SessionWeight'])


As you can see the answer to the calculation above is right, the answer is 41 .2 as it adds up the two session marks, divide by 100 and then times it by the total amount of the percentage.

But I want to include a total mark where except it is out of the total session percentage (60% for above example), it is out of a 100% but I can not work as simple as that as in above example one session is worth more than other. I have worked out that the answer for the total mark of the above example out of 100% should be 69, but how do I achieve this in my calculation.

Thank you and any help is much appreciated

So how