This speedup is due to the fact that the array is a fixed size, not a variable-sized one like the default PHP one is, and that non-numeric indexes are not allowed.

A variable of array type has three important limitations: Its size is fixed, the size must be known at compile time, and the array exists only until the end of the block in which it was defined.

A parameter self-learning algorithm is presented after defining data structure and variable array to improve the prototype's adaptability to different size of workpieces.