Re: docs for (double) related to (int) or ???

J. Frank Parnell wrote:
On Fri, 29 May 2009 15:50:09 -0400, Jerry Stuckle <jstucklex@xxxxxxxxxxxxx>
wrote:

J. Frank Parnell wrote:
hello, I inherited this:

function microtime_float (){
list ($usec, $sec) = explode (' ', microtime ());
return (double)$usec + (double)$sec;
}

double seems to be related to int.
Can some one explain (double) or point to some docs or explanations?

thanks, J
double is just a floating point value. But this code looks bad - if it's supposed to return the microtime in seconds, it should be

return ((double)$usec) / 1000000 + double($sec);

well cool...but why double? isnt "double" ( $num * 2)? or did i miss something
in my extensive (read: high school. smirk) education?

the full usage of the function is much like in the php man(thanx yawnmoth):

$res_start = microtime_float();
//lotsa code
$res_stop = sprintf("%2f", microtime_float() - $res_start);
echo "Page load time: $res_stop seconds";

do you still believe the function to be bad?

No double is a commonly used term for floating point representations. For instance, in C, a float may use two bytes of storage, while a double could use four bytes (or four and eight, respectively). With more bits, you have higher precision. double has approximately twice the precision of a float.

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