initialise
initialise(count: Integer64) updating;
The initialise method of the Array class initializes an array with null entries up to a size specified by the value of the count parameter.
If you know that an array will contain a large number of entries, use the initialise method to preallocate space for the array rather than have it grow incrementally.
You can also use the initialise method to reinitialize an array efficiently without needing to call the clear method.