Appending array element without using Array.append

Learning
1

Hi,

I want to use the Ocaml array instead of list because the memory footprint for array is less than the list.
I have to store big information in array. I am using Array.append to add a new element.
However, Ocaml documentation for Array.append says:

Array.append v1 v2 returns a fresh array containing the concatenation of the arrays v1 and v2

It returns a fresh array without modifying the existing array.
After appending many items in the array, array.ml append function throws Out-of_memory error.
Is there any other alternative to this function? [Or perhaps my understanding of Array module is not good]

Thank you in advance.

2

It’s hard to give you a sound suggestion because we don’t know what you’re trying to achieve.
If you know or can guess the size of the array in advance, just start with a “big enough” array.
Otherwise you might want to consider libraries that implement “dynamic arrays”.

3

Actually, I do not know the size of array in advance.
Is there any way to resize the array as and when required?

4

AFAIK, in OCaml with the standard library you cannot do that (to a certain extent you can use Array.append and Array.blit). There are however other libraries that implement dynamic arrays: http://ocaml-batteries-team.github.io/batteries-included/hdoc2/BatDynArray.html

5

An array that resizes as required is normally referred to as a vector. You may want to search for ‘ocaml vector’.