Posted by Bob Stearns on 08/12/05 06:09

TheTeapot wrote:

> Hi all,
>
> Here's a puzzle:
> // Say I have an array of numbers set up like so:
> $arr = array(15,16,17,100,121,1000);
>
> // How can I create a function so that I can use it like so:
> addleadingzeros_arr($arr);
>
> // and have the output look like:
> // array("0015","0016","0017","0100","0121","1000");
>
> Or, if the function only does one value like shown, so I can loop the
> array through, modifying each seperately.
> addleadingzeros_int(32);
> // Outputs: "0032"
>
> I'd prefer the first one though.
>
> Thanks,
> TheTeapot
>


function addleadingzeros_arr($arr) {
$res = array();
foreach($arr as $x)
if(abs($x)>$maxx) $maxx = abs($x);
mult = 1;
len = 0;
while(mult<maxx) {
mult *= 10;
len += 1;
}
foreach($arr as $k => $x)
$res[$k] = $x<0?"-":"" . right(mult+abs(x),len);

return $res;
}

Will do the trick without all the overhead of sprintf. If you know how
many leading zeroes you want, the first two loops can be omitted and the
correct values (10000 and 4 for instance, in your specified case). The
conditional and the abs can be omitted if you'll always have non
negative numbers in $arr. The code can be simplified if $arr is
subscripted by 0-n.

Untested, off the top of my head. Try before committing real data. YMMV.

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