sort to accept DynamicView and [begin,end) indices

[bathmatt]

I need to sort DynamicViews. To do so I need to create a subview of a dynamic view.
Here is my routine

Can we add at least subviews with slightly smaller lengths for dynamic view?

  int max_elems = MapContainer::getElementMap()->getNodeNumElements();
  int min_elems = 0, num_elems = max_elems-min_elems+1;
  BinOp binner(num_elems, min_elems, max_elems);

  Kokkos::pair<size_t, size_t> reduced_size(0,size());
  KeyViewType local_ielement = Kokkos::subview(element_, reduced_size);

  Kokkos::BinSort<KeyViewType , BinOp > Sorter(local_ielement,binner,false);
  Sorter.create_permute_vector();
  Sorter.sort< KeyViewType >(local_ielement);

  Sorter.sort(Kokkos::subview(x_, reduced_size));
  Sorter.sort(Kokkos::subview(x_ref_, reduced_size));
  Sorter.sort(Kokkos::subview(v_, reduced_size));
  Sorter.sort(Kokkos::subview(v_ref_, reduced_size));

[crtrott]

Would it be sufficient to provide only a subview function outside of parallel kernels?
Also: as a minimum requirement subviews would not be growable themselves, and shrinking the original view while a subview exist is undefined behavior.

[bathmatt]

Thats fine for my use case

…

On Sat, Mar 18, 2017 at 9:49 AM, Christian Trott ***@***.***> wrote: Would it be sufficient to provide only a subview function outside of parallel kernels? Also: as a minimum requirement subviews would not be growable themselves, and shrinking the original view while a subview exist is undefined behavior. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#691 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AOPDIGudSWt7kahvSPcQ82d5cfIYjwA1ks5rm_z6gaJpZM4MhGVJ> .

[hcedwar]

@bathmatt : how urgent?
This appears to be two enhancements:

• subview of DynamicView and
• sort algorithm to accept subview of DynamicView

To create a subview it would have to be aligned with the DynamicView chunking - it cannot be arbitrary.

[bathmatt]

Pretty urgent. couple weeks...

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On Wed, Apr 5, 2017 at 12:22 PM, hcedwar ***@***.***> wrote: @bathmatt <https://github.com/bathmatt> : how urgent? This appears to be two enhancements: - subview of DynamicView and - sort algorithm to accept subview of DynamicView To create a subview it would have to be aligned with the DynamicView chunking - it cannot be arbitrary. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#691 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AOPDIENrznK2qKXzyJpSNmWHXbvUCQ_6ks5rs9vdgaJpZM4MhGVJ> .

[hcedwar]

Follow up conversation with @bathmatt
Root requirement is to sort a subrange of a DynamicView.
The subview discussion is only due to the current sort functions' interface only working on a full View so that a subview must currently be created to sort a subrange.
The root requirement can be satisfied at lower effort with sort functions that accept a DynamicView and [begin,end) range indices.

[hcedwar]

@bathmatt
A unit test applying Kokkos::sort to a Kokkos::Experimental::DynamicView is now in the develop branch.
https://github.com/kokkos/kokkos/blob/develop/algorithms/unit_tests/TestSort.hpp#L206
Please have a look as to whether the capability is sufficient for your use case.