[RESOLVED] Adding array values with foreach loop

[revez2002]

I use an array to hold two values from a database search: key = percentage, and value = username. I want to sum all of the percentage (key) values, and it has been suggested that the best way to do this is using the foreach loop. Unfortunately, I really have a hard time wrapping my head around its use.

Can anyone suggest how I can iterate through a foreach loop and sum up all of the percentages based on a matching username value.

Thanks in advance for any help.
Revez

[benracer]

foreach($array  as $percentage => $username){
$total[] = $percentage;
}

$total = array_sum($total); 

echo $total;

[NogDog]

Assuming I understand the question correctly:

$sum = 0;
foreach($array as $key => $value)
{
   $sum += $key;
}
echo $sum;

[revez2002]

Thanks to all for the suggestions.

However, using the code posted, I get a sum of all of the values in the array.

Sorry if my original posting wasn't clear.

I have an array named rank that I use to gold the values of two variables: percentage and username. Percentage is the key and usename is the value. This array has more than one element with matching values (i.e. usernames). I want to sum up only the percentages in the array that have a matching value (username).

Thanks again for the help, and I hope that my question makes more sense this time around.

revez

[benracer]

could you post your code so far...

[revez2002]

Hello,

I create an array named rank:

$rank = array();

I then take two values from various database searches, and populate the rank array as follows:

$rank[$percentage] = $username;

revez

Best a I can figure, the code I need to use should look something like this:

  foreach ($rank as $percentage => $username) {]
    if($???????? == $username) {
      $sum += $percentage;
    }
  }

Its filling in the $???????? part that I can't figure out.

revez

[bpat1434]

$result = array();

foreach($rank as $percent => $username)
{
    if(!isset($result[$username]))
        $result[$username] = $percent;
    else
        $result[$username] += $percent;
}

print_r($result);

Not guaranteed to work, but should push you the right way.

[revez2002]

OK, it looks like we're making some progress! The output seems to be accurate, but there appears to be one small problem - it looks like username is now the key, and I want to sort my results by percentage (highest to lowest).

None of the functions that I have tried (ksort, natsort, asort, etc.) will work.

revez

[bpat1434]

natsort($result) should sort the $result array by percentages.... have you done:

print_r($result);
natsort($result);
print_r($result);

[revez2002]

Yes, I have used the natsort($result), and it does appear to list the results in percentage order, but from lowest down to highest. I need the list to display from highest to lowest, and none of the sorting functions (or combinations of them) will display highest to lowest.

revez

[bpat1434]

Oh, well that's not "a problem", that's just a case of "it's not what I want exactly".

Just reverse the array 😉

natsort($result);
$result = array_reverse($result, true);

EDIT: Note that the second parameter of "true" in the array_reverse function is required to keep the array keys.

[revez2002]

Here is the code that I am using. It is doing most of what it should except for the sorting issue. Also, when I call print ($rows[key]);, I get the username instead of the percentages.

<?php
$result = array();							¨

foreach($rank as $percentage => $username) {

if(!isset($result[$username])) {
$result[$username] = $percentage;

} else {
$result[$username] += $percentage;
}										
}								

krsort($result);													
for ($m=1; $m <= count($result); $m++) {

$rows = each($result);						

if(!empty($rows[key])) {

echo '<tr>';
echo '<td height="22" width="5"></td>';
echo "<td class=\"mid_blue_02\" width=\"50\" align=\"left\" valign=\"middle\" bgcolor=\"#EBEBEB\">&nbsp;$m</td>";
echo "<td class=\"mid_blue_02\" width=\"".(($cell_001 - 80) * 0.50)."\" align=\"left\" valign=\"middle\" bgcolor=\"#EBEBEB\">";
print ($rows[key]);
echo "</td>";
echo "<td class=\"mid_blue_02\" width=\"".(($cell_001 - 80) * 0.50)."\" align=\"left\" valign=\"middle\" bgcolor=\"#EBEBEB\">";
print ($rows[value]);
echo "%</td>";
echo '<td width="15" bgcolor="#EBEBEB"></td>';				
echo '</tr>';
echo '<tr>';
echo '<td colspan="4" height="1" width="'.$cell_001.'" bgcolor="#CCCCCC"></td>';
echo '<td width="15" bgcolor="#EBEBEB"></td>';
echo '</tr>';							
}								
}
?>

[revez2002]

Hey there bpat1434,

We must have been posting at the same time, and I didn`t see your last message. I implemented the fix that you suggested (using array_reverse), and everything is working exactly as required.

I must have spent over 6 hours trying to figure this out on my own, but at least it is now working. Thanks so much for your help in resolving this!!!

Cheers!
revez 🙂