[brendano]

Ah, wonderful! So if I understand this correctly, this doesn't give C/Fortran access to Java-native primitive arrays; but instead, it's specific to NIO byte buffers (and then the matrix libraries have to build on top of that). But that should be fine for doing R replacements, at least in theory.

(Personally, when programming Java I find it more convenient to use primitive arrays as opposed to matrix libraries, but that might be dependent on the operations I tend to do: lots of increment/decrements and only occasional linear algebra. I guess this isn't exactly relevant to the R replacement question.)

[pron]

Java also gives native libraries direct access to primitive arrays, but that requires pinning them in place for the duration of the call (i.e. not letting the GC move them) so it incurs some performance penalty.

Direct byte buffers are very common in high-performance Java code. Reading/writing from/to those buffers can be made just as fast as plain Java arrays.

[brendano]

Thanks for the information. Sorry I was misinformed before...