Template parameters of the containers and views¶
TraversalOrder¶
TraversalOrder is a type encoding of the optimal traversal in memory. Default is void, corresponding to as regular C-style ordering (slowest index first).
The traversal of the arrays (iterators, foreach loop) will be written and optimised for this order.
It is indeed sometimes necessary to know at compile time the traversal order to generate an optimal code. The default (C-style) is sufficient is most cases, but not always…
More explanations here…
Note that this notion is completely independent of the real memory layout of the array, which is a runtime parameter.
The code will be correct for any order, but may be faster for the TraversalOrder.
TraversalOrder is not present for vector since there is only one possibility in 1d.
TODO : document the various possibility beyond C style.
| TraversalOrder | Meaning |
|---|---|
| void | C style traversal (lowest index first). |
| _traversal_fortran | Fortran style traversal (last index first) |
| _traversal_dynamical | Traverse in the order specified by the memory layout |
| _traversal_custom<2,1,0> | Traverse in the order specified by the permutation (2,1,0) |