Question

I’m trying to create a simple average calculator using an array with randomly generated numbers. I think the code is pretty solid but I’m being returned this error:

Notice: Undefined offset: 10 in ../average/averageresults.php on line 31

Line 31:

for ($i=0; $i<=10; $i++)   {   echo $array[$i]."<br />";   }

Rest of code is as follows:

<?php
$array = array();

    $array[]=rand(1, 99);
    $array[]=rand(1, 99);
    $array[]=rand(1, 99);
    $array[]=rand(1, 99);
    $array[]=rand(1, 99);
    $array[]=rand(1, 99);
    $array[]=rand(1, 99);
    $array[]=rand(1, 99);
    $array[]=rand(1, 99);
    $array[]=rand(1, 99);

$i=0;
$sum = array_sum($array);
$count = count($array);
$avg = $sum/$count;

for ($i=0; $i<=10; $i++)
  {
  echo $array[$i]."<br />";
  }
echo "The average of these numbers is: ".$avg;

 ?>

Answer 1

You’re “off by 1”. The array has 10 elements, 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9. There is no 10.

Change your for loop to:

for ($i=0; $i<10; $i++) “less than” instead of “less than or equals to”