in reply to Memory efficient way to deal with really large arrays?

Is there any way you can tell perl a scalar is to be a int only of a certain size?

See PDL. I have no experience with this software other than knowing of its existence, but I think it might be able to do this trick.

The other idea I have is [to use] a gigantic scalar, and then pack/unpack the values in/out of the scalar ...

Take a look at BrowserUk's ultimate solution for the problem posed here. substr is used rather than pack/unpack.

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