I need a multi-dimensional pre-filled with a numeric value, as so;
for($m = 0; $m <= 149; $m++){
for($n = 0; $n <= 99; $n++){
$pitchDef[$m][$n] = 999;
}
}
But would it be faster for PHP to simply read the arrays pre-populated?
In other words is it faster for php to read or create an array?
Every assigning a new variable to memory requires first to find out how memory is needed, then allocate it from the system and then write. In these three steps the writing itself (the last operation) is the same (I suppose) time as reading, however the whole assignment is longer, because it has two more steps.
If you have your array, in this example, you don't even say how large the array is, so every single writing PHP requires to change structure of the whole array, then allocate memory for an element and then write it.
At least you could at the very beginning allocate memory for the array like ExplesionPills wrote, then access the array.
The best idea is to compare ("benchmark") two methods by making them run many times ("many" is for example 1 million) and see execution times.
array_fill(0, 150, array_fill(0, 100, 999));
I'm pretty sure that's as fast as you can get .. it's much faster than two for loops, but both are still trivially fast when run individually.
createdo you mean to allocate space for, and populate all dimensions of, the array? Or just the actual allocation? Obviously if you need to create and set a large range of values in an array, it'll be slower than a simple read operation.