note 31675 deleted from language.operators.bitwise by sniper
| From: | sniper@php.net | Date: | Mon, 13 Oct 2003 00:13:32 +0000 |
| Subject: | note 31675 deleted from language.operators.bitwise by sniper | ||
| References: | 1 | Groups: | php.notes |
| Request: | Send a blank email to php-notes+get-58414@lists.php.net to get a copy of this message | ||
Note Submitter: ktulu@csionline.net
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A previous comment posted a function flags2array. However, I noticed with this that the indexes of
the array are opposite of what you would expect... ie:
flags2array(175) =
bits[0] = 1
bits[1] = 0
bits[2] = 1
bits[3] = 0
bits[4] = 1
bits[5] = 1
bits[6] = 1
bits[7] = 1
But 175 = 1 + 2 + 4 + 8 + 32 + 128 = 2^0 + 2^1 + etc...
The indexes of the bits array do NOT correspond to the power of 2, the are equal to 7-power (I
think)... So I modified the function to the following:
function flags2array($dec)
{
$bits= Array();
$bin = decbin($dec);
for ($i=0; $i<strlen($bin); $i++)
$bits[strlen($bin)-$i-1] = $bin{$i};
return $bits;
}