PHP array sums of points and average

You have to use some functions :

To print points, you can use implode(' ', $numberarray) It will show points separated with a space. (See implode())

Sum can be get by function array_sum() : This function calculate the sum of values in an array.

$sum = array_sum($numberarray);

Finally, average can be get by this code :

$average = array_sum($numberarray) / count($numberarray); 

Result :

$points = implode(' ', $numberarray);
$sum = array_sum($numberarray);
$average = array_sum($numberarray) / count($numberarray); 

echo "Points were: $points\n";
echo "Sum of points: $sum\n";
echo "Average of points: $average";

About code you have done :

for ($i=0; $i<=$numberarray.length;$i++)

This will not work. In PHP, if you want to get number of elements in array, you have to use count()

for ( $i = 0 ; $i < count($numberarray) ; $i++ ) { ... }

Also, you write echo "points were:" ; between for() and {. You will get a Fatal Error. You have to move your echo before loop

echo "points were:" ; 
for ( $i = 0 ; $i < count($numberarray) ; $i++ ) {
    $points = $numberarray[$i];
    $sum = $points+$sum; // You can also do $sum += $points;
    echo $points." ";
}

About your while() loop, it will loop infinite and you don't need to do a loop. You can simply do :

$average = $sum / count($numberarray);

You final code will look like :

$numberstring = $_GET['numberstring'];
$numberarray = explode(',',$numberstring);

echo "Points were:" ; 
for ( $i = 0 ; $i < count($numberarray) ; $i++ ) {
    $sum += $numberarray[$i];
    echo $numberarray[$i]." ";
}
echo "\n";

$average = $sum / count($numberarray);

echo 'Sum of points: '.$sum."\n";
echo 'Average of points: '.$average;

EDIT with some validations/optimizations :

$numberstring = $_GET['numberstring'];
$numberarray = explode(',',$numberstring);
$cptElements = count($numberarray); // create a variable to not call count() multiple times.

if ( $cptElements )
{
    $numberarray = array_map ('intval', $numberarray); // convert all values to int.

    echo "Points were:" ; 
    for ( $i = 0 ; $i < $cptElements ; $i++ ) {
        $sum += $numberarray[$i];
        echo $numberarray[$i]." ";
    }
    echo "\n";

    echo 'Sum of points: '.$sum."\n";
    echo 'Average of points: '.($sum / $cptElements);
}
else
{
    echo 'No points';
}

Shouldn't something like this do all you want:

$string = $_GET['numbers'];
$numbers = array_map('intval', explode(',', $string));

$sum = array_sum($numbers);

$average = $sum / count($numbers);

The array_map function can execute another function on all elements in the array (this one makes sure you are dealing with only integer values). Try using as much functions from PHP as possible; array_sum() and count(). The first one adds up all the elements in the array, and the second one counts the number of elements in the array. These two function combined can generate the average for you.

In your example-code, I can see for ($i=0; $i<=$numberarray.length;$i++) $numberarray.length looks like javascript to me... not PHP, try using the count() method mentioned earlier

Use this

$numberstring = $_GET['numberstring'];
$numberarray = explode(',',$numberstring);


echo "Points were: ".$numberstring;*/
echo "Sum of points: ".array_sum($numberarray );
echo "Average of points: ".array_sum($numberarray)/count($numberarray);

Here you go

<?php

        $numberstring = $_GET['numberstring'];
        $numberarray = explode(',',$numberstring);

        // Your code here
        $sum = array_sum($numberarray);
        $count_arr = count($numberarray);
        $average = $sum/$count_arr;
        $points = str_replace(',',' ', $numberstring);

        echo "Points were: $points\n";
        echo "Sum of points: $sum\n";
        echo "Average of points: $average";
     ?>

PHP does not have a length property on Arrays. Use count($array_here). Also, Object (class in PHP) properties are accessed with -> not ., and you're not using an Object. In your case you don't even need a loop. Your PHP should look more like:

<?php
function array_average($ary){
  return array_sum($ary)/count($ary);
}
if(isset($_GET['numberstring'])){
  $number_string = $_GET['numberstring'];
  $number_array = explode(',', $number_string);
  echo 'points were:'.$number_string.'<br />'.
  'sum of points:'.array_sum($number_array).'<br />'.
  'average:'.array_average($number_array);
}
?>