## Test: set duplicates vs. !isset

This checks the cost of writing vs. the cost of checking if you're already written - for values that commonly overlap.

Run this test again Return to test menu## Result: Discarded

The test labeled "**set**" was the faster by

*0.0024*seconds, (0.330% faster)

The **set** test took **0.7287** seconds.

The **!isset()** test took **0.7311** seconds.

## Nitty-Gritty

Each test case ran 20 random code order iterations consisting of 143,763 loops for a total of 2,875,260 runs.

- Line execution difference (0.000001) milliseconds.

- Avg difference (0.121) milliseconds per 143,763 loops.

- Total difference 2.41 milliseconds for 2,875,260 loops

The iteration variablity for Code 1 was (6.3894) milliseconds and Code 2 was (7.9008) milliseconds. The lower and the closer together there values are the more accurate the results are.

## Code

The first test, "**set**", was:

$array = array(); for ($n = 0; $n < 100; $n++) { $k = floor($n / 12); $array[$k] = $n + 42; }

The second test, "**!isset()**", was:

$array = array(); for ($n = 0; $n < 100; $n++) { $k = floor($n / 12); if (!isset($array[$k])) $array[$k] = $n + 42; }