time profile function...how does this work?

[sneakyimp]

this is from my php docs....not sure what the getmicrotime() function is doing....seems to me that adding microseconds and seconds doesn't make sense

function getmicrotime(){ 
   list($usec, $sec) = explode(" ",microtime()); 
   return ((float)$usec + (float)$sec); 
   } 

$time_start = getmicrotime();

for ($i=0; $i < 1000; $i++){
   //do nothing, 1000 times
   }

$time_end = getmicrotime();
$time = $time_end - $time_start;

[jazz_snob]

According to the good book :

Both portions of the string are returned in units of seconds.

[theslinky]

Wow... it's been a while since I've posted on phpbuilder (I think the last time was sometime in early 2003??)

Anyway, sneakyimp: I think your question is why do you add usec and sec together? That's because microtime returns the usec part in a decimal form. So it's actually usec in the "sec" form just with the decimal. So eg:

print microtime();

would result in something like:

0.36441900 1100236193

So by adding the two (and making sure you cast it as float before adding -- so it doesn't get interpreted as a string and hence the usec part becoming zero), you get the full seconds part.

hope this helps,
-sridhar

[Weedpacket]

As an aside, since PHP5, passing an argument of [man]true[/man] to microtime() will cause it to give the same result that in earlier versions required a function equivalent to the posted getmicrotime() function.