Historical Results
Based on (2) saved test runs, The test labeled "is_float" was (on average) the faster by 0.0136 seconds, (2.104% faster)
The is_float test took 0.6307 seconds.
The Casting test took 0.6443 seconds.
Nitty-Gritty
Each test case ran 20 random code order iterations consisting of 161,508 loops for a total of 3,230,150 runs.
- Line execution difference (0.000004) milliseconds.
- Avg difference (0.000) milliseconds per 161,508 loops.
- Total difference 13.55 milliseconds for 3,230,150 loops
The iteration variablity for Code 1 was (0.0000) milliseconds and Code 2 was (0.0000) milliseconds. The lower and the closer together there values are the more accurate the results are.
Code
The first test, "is_float", was:
$a = is_string($GLOBALS['test']);
The second test, "Casting", was:
$a = (string) $GLOBALS['test'] === $GLOBALS['test'];