How to get rid of undefined offset?

Question

I am trying to remove undefined offset error from the following code but could not figure it how.

$number = 20;
$pack = 10;
$i = 0;
while ($number % $pack == 0)
{
    $number = $number / $pack;
    $i++;
}
list($firstpart,$secondpart)=explode('.', $number);

echo $firstpart;
echo '<br>';
echo isset($secondpart)? number_format($secondpart,0):'0';

This code gives me correct answer but it outputs the following error:

E_NOTICE : type 8 -- Undefined offset: 1 -- at line 11

How do I change my code to remove the error. In a case like when $number=20.5, there is no error. Thanks.

`explode('.', $number)` is set to `$firstpart`, but what's about second part ? — w3spi, Oct 27 '16 at 18:40
Some time $number can have decimal point. That's why I need the second part also. — Hanner, Oct 27 '16 at 18:42
@Zl3n What if the result of the division produces more than one decimal point? You will lose that precision with your proposed solution. — MonkeyZeus, Oct 27 '16 at 18:49
`list($firstpart, $secondpart) = explode('.', $number.(strpos($number, '.') === false ? ".0" : ''));` — MonkeyZeus, Oct 27 '16 at 18:52
Please can you post your answer with explanation because it works and I want to accept. — Hanner, Oct 27 '16 at 18:54

AbraCadaver · Answer 1 · 2016-10-27T18:57:24.367

2

Since you use two arguments for list() it attempts to reference index [0] and [1] from the explode(), however there is only [0] because explode() returns only one array element when there is no .. Use this instead:

$parts = explode('.', $number);
echo $parts[0];
echo isset($parts[1]) ? number_format($parts[1] ,0) : '0';

edited Oct 27 '16 at 18:57

answered Oct 27 '16 at 18:54

AbraCadaver

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score 0 · Accepted Answer · answered Oct 27 '16 at 18:58

This will work:

list($firstpart, $secondpart) = explode('.', $number.(strpos($number, '.') === false ? ".0" : ''));

And here is an explanation so I don't get accused of witchcraft :-)

list($firstpart, $secondpart) =
    explode(
        '.', // explode on a period
        $number.(strpos($number, '.') === false ? ".0" : '') // if the number does not contain a period then manually add ".0" so that explode can work but if it does then just leave it as-is
    );

How to get rid of undefined offset?

2 Answers2