Dimensions

The maximum number of dimensions supported by the GIO library¹is now coded as a unique parameter named GDF_MAXDIMS; it has been increased from 4 to 7² between the two GDF versions. The SIC arithmetic engine has been prepared during the summer 2011 to be able to deal with such data cubes. Increasing this value is technically possible at the cost of hand-made adjustments of the GIO library, of the SIC arithmetic engine, maybe of the tasks and procedures, and probably on the global efficiency.

The maximum number of dimensions supported by the GDFV2 is also set to GDF_MAXDIMS. Increasing it to 8 is technically possible but useless without the GIO and SIC libraries also upgraded. 9 dimensions and beyond can not be currently supported by the GDFV2, since the DESCRIPTION section would overflow the first header block.

In every case (GDFV2, GIO, SIC etc), increasing the maximum number dimensions beyond 7 implies the support by the compilers of the rank 15 arrays from the Fortran 2008 standard. This, because we tend more and more to map the GDF or SIC data block on Fortran arrays.

In the GDFV1, the number of elements per dimension and the total number of elements in the cube were stored in a standard integer, limited to $2^{31}-1$. In the GDFV2, these elements are now stored as long integers (under 64 bits machines) and are now limited to $2^{63}-1$.