Re: Fast access multi-dimensional arrays? (int type)

Kevin wrote: 
Hi all,
I have a question of: is there any way we can create a
multi-dimensional arrays data structure, each grid item is a "int",
with fast access for operations like "increase value in one grid", or
get that value?


Does the total matrix size fit easily in cache? If you have only a
two-dimensional problem, with 4 to 10 elements in each dimension,
obviously the problem does fit.

If yes, then index arithmetic is probably the place to look for
improvements.

If no, then you need to think of your problem in terms of transfers
between memory and cache. Relationships between the order of access in
loops and the order of placement in memory matter. Generally, you want
the innermost loop to scan the dimension that is consecutive in memory.

Patricia
.

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