[SOLVED] calculating array

[kaveman50]

does anyone know how to make it so that you can make user input 7 grades and ouput average and drop the 2 lowest scores?

This is all i know how to do

 

<form method='post' action=''>

Enter Student's Name:
<br/> <input type="text" name="num1" value = " " />  
<br/>
<br/>
Enter Seven Tests Scores Here: 
<br/><input type="text" name="num1" value = "<?=$_POST['Steve']?> " />  
<br/><input type="text" name="num1" value = "<?=$_POST['Steve']?> " />  
<br/><input type="text" name="num1" value = "<?=$_POST['Steve']?> " />  
<br/><input type="text" name="num1" value = "<?=$_POST['Steve']?> " />  
<br/><input type="text" name="num1" value = " <?=$_POST['Steve']?>" />  
<br/><input type="text" name="num1" value = "<?=$_POST['Steve']?> " />  
<br/><input type="text" name="num1" value = " " />  

<br/><input type='Submit' name='Submit' value="Submit" />
</form>

<?


$steve1=$_POST['Steve'];
$a=array($_POST['Steve']);
print_r (array_sum($a)) ;













?>

[mikesta707]

function getAverage($array){
//get lowest values, and counter
$counter = 0;
$lowest = 9999;//arbitrarily high values
$secondLowest = 1000;
foreach($array as $arr){
  $counter += $arr;
  if ($arr < $secondLowest){
    $secondLowest = $arr;
    if ($secondLowest < $lowest){
      $lowest = secondLowest;
    }
  }
}//end foreach
$counter -= ($lowest + $secondLowest);//drop 2 lowest
return $counter / (count($array) - 2);//return average
}//end func

 

untested, so logic might be slightly off, but i think thats about right

 

[kaveman50]

and then would i just do print_r($counter) and leave my posts the way they are after i add in your code?

[Alex]

Something like this would also work:

 

<?php
function getAverage($arr)
{
asort($arr); array_shift($arr); array_shift($arr);
return array_sum($arr) / count($arr);
}

 

To use it in your form you'd make all the text inputs named 'num[]', then do something like:

 

echo getAverage($_POST['num']);

[mikesta707]

ahh wow AlexWD's solution is way better way way better. you would just echo the returned value. completely forgot about asort haha

[kaveman50]

Thanks guys. =)

[kaveman50]

Oh wait it's saying Warning: asort() expects parameter 1 to be array, null given in

 

/Applications/XAMPP/xamppfiles/htdocs/webalizer/av.php on line 25

 

Warning: array_shift() expects parameter 1 to be array, null given in /Applications/XAMPP/xamppfiles/htdocs/webalizer/av.php on line 25

 

Warning: array_shift() expects parameter 1 to be array, null given in /Applications/XAMPP/xamppfiles/htdocs/webalizer/av.php on line 25

 

Warning: array_sum() expects parameter 1 to be array, null given in /Applications/XAMPP/xamppfiles/htdocs/webalizer/av.php on line 26

 

Warning: Division by zero in /Applications/XAMPP/xamppfiles/htdocs/webalizer/av.php on line 26

 

<form method='post' action=''>


Enter Student's Name:

<br/> <input type="text" name="num1" value = " " />  

<br/>

<br/>

Enter Seven Tests Scores Here: 

<br/><input type="text" name="num1" value = "<?=$_POST['num']?> " />  

<br/><input type="text" name="num1" value = "<?=$_POST['num']?> " />  

<br/><input type="text" name="num1" value = "<?=$_POST['num']?> " />  

<br/><input type="text" name="num1" value = "<?=$_POST['num']?> " />  

<br/><input type="text" name="num1" value = " <?=$_POST['num']?>" />  

<br/><input type="text" name="num1" value = "<?=$_POST['num']?> " />  

<br/><input type="text" name="num1" value = "<?=$_POST['num']?> " />  


<br/><input type='Submit' name='Submit' value="Submit" />

</form>


<?


$arr=array($_POST['num']);


function getAverage($arr)

{

	asort($arr); array_shift($arr); array_shift($arr);

	return array_sum($arr) / count($arr);

}




echo getAverage($_POST['num']);




?>[/Code]

 

[Alex]

Make sure the post was submitted:

 

if(isset($_POST['Submit']))
{
     echo getAverage($_POST['num']);
}

 

isset()

[kaveman50]

For some reason it still gives me all those warnings. The only difference now is that it appears after you press submit. Do I also need to do the <?=$=......?> for the value of my submit button?

[Alex]

You didn't listen to what I said before.

To use it in your form you'd make all the text inputs named 'num[]', then do something like:

You can leave the values that you have set if you want (although, if you have error reporting high enough those will throw and undefined index warning, so ideally you should use isset() for those as well), but you might want to remove some of the spaces you have in there.

[kaveman50]

What spaces are you talking about?

[Alex]

Things like:

 

<br/><input type="text" name="num1" value = "<?=$_POST['num']?> " />

 

Notice you have a space after <?=$_POST['num']?> before "

[mikesta707]

shouldn't it be $_POST['num1'] not $_POST['num']?

[Alex]

shouldn't it be $_POST['num1'] not $_POST['num']?

Not if kaveman50 followed my suggestion.

[mikesta707]

ahh thought i say a 1 in your suggestion

[kaveman50]

I'm sorry but I still don't really get what you mine by putting a blank [] after the num. I tried it once and it gave me even more errors. The most recent code I have doesn't say any errors when I click submit, but it returns zero.

 

<form method='post' action=''>

Enter Student's Name:
<br/> <input type="text" name="num1" value = " " />  
<br/>
<br/>
Enter Seven Tests Scores Here: 
<br/><input type="text" name="num1" value = "<?=$_POST['num']?>" />  
<br/><input type="text" name="num1" value = "<?=$_POST['num']?>" />  
<br/><input type="text" name="num1" value = "<?=$_POST['num']?>" />  
<br/><input type="text" name="num1" value = "<?=$_POST['num']?>" />  
<br/><input type="text" name="num1" value = "<?=$_POST['num']?>" />  
<br/><input type="text" name="num1" value = "<?=$_POST['num']?>" />  
<br/><input type="text" name="num1" value = "<?=$_POST['num']?>" />  

<br/><input type='Submit' name='Submit' value="Submit" />
</form>

<?

$arr=array($_POST['num']);

function getAverage($arr)
{
asort($arr); array_shift($arr); array_shift($arr);
return array_sum($arr) / count($arr);
}


if(isset($_POST['Submit']))
{
echo array_sum($arr) / count($arr);

}

?>

[Alex]

You put num[] so that it can be an array.. You were also creating an array with one element which was an array, which is why you were getting 0. Here:

 

<form method='post' action=''>

Enter Student's Name:
<br/> <input type="text" name="num1" value = " " />  
<br/>
<br/>
Enter Seven Tests Scores Here: 
<br/><input type="text" name="num[]" value = "<?=$_POST['num'][0]?>" />  
<br/><input type="text" name="num[]" value = "<?=$_POST['num'][1]?>" />  
<br/><input type="text" name="num[]" value = "<?=$_POST['num'][2]?>" />  
<br/><input type="text" name="num[]" value = "<?=$_POST['num'][3]?>" />  
<br/><input type="text" name="num[]" value = "<?=$_POST['num'][4]?>" />  
<br/><input type="text" name="num[]" value = "<?=$_POST['num'][5]?>" />  
<br/><input type="text" name="num[]" value = "<?=$_POST['num'][6]?>" />  
<br/><input type='Submit' name='Submit' value="Submit" />
</form>

<?
$arr = $_POST['num'];

function getAverage($arr)
{
asort($arr); array_shift($arr); array_shift($arr);
return array_sum($arr) / count($arr);
}


if(isset($_POST['Submit']))
{
echo array_sum($arr) / count($arr);
}

?>

[kaveman50]

It still comes up as 0

[Alex]

No it's not, I even tested it.

[kaveman50]

Oh I didn't see the array POST you added in the second time. My bad. Thanks for the help.

[kaveman50]

Oh yeah how would I drop the 2 lowest scores?

[kaveman50]

.

[kaveman50]

.

[Alex]

The function that I originally posted for you to use includes this functionality.

[kaveman50]

It just displays the average without it rounded off, though.