Restriction when indexing large arrays

Hi there, on 64bit platforms: why does matlab only allow 48bit integers for indexing arrays / creating (sparse)matrices, while on 32bit platforms 31bit indices are allowed?

Quote from "doc sparse": [...] S = sparse(i,j,s,m,n,nzmax) [...] Note: If any value in i or j is larger than 2^31-1 for 32-bit platforms, or 2^48-1 on 64-bit platforms, then the sparse matrix cannot be constructed. Quote end

Any hint is appreciated!

Answer 1

[Andreas Goser]

I'd say this question is a side answer from this solution:

"The current 64-bit processors from AMD and Intel do not actually support 64-bit addressing. They only have 40 physical address pins and can support 48-bits virtual addressing."

[Lars Ludwig]

thank you for the link - this helps!