Triangle Counts C++ API (#2233)

Define C++ API for triangle counting.

Authors:
  - Seunghwa Kang (https://github.com/seunghwak)

Approvers:
  - Chuck Hastings (https://github.com/ChuckHastings)
  - Joseph Nke (https://github.com/jnke2016)

URL: #2233

cpp/CMakeLists.txt

@@ -240,6 +240,8 @@ add_library(cugraph
     src/visitors/bfs_visitor.cpp
     src/visitors/rw_visitor.cpp
     src/visitors/graph_make_visitor.cpp
+    src/community/triangle_counts_sg.cu
+    src/community/triangle_counts_mg.cu
 )
 
 set_target_properties(cugraph

cpp/include/cugraph/algorithms.hpp

@@ -27,6 +27,7 @@
 #include <cugraph-ops/graph/sampling.hpp>
 
 #include <raft/handle.hpp>
+#include <raft/span.hpp>
 
 namespace cugraph {
 
@@ -1534,4 +1535,31 @@ uniform_nbr_sample(raft::handle_t const& handle,
                    std::vector<int> const& h_fan_out,
                    bool with_replacement = true);
 
+/*
+ * @brief Compute triangle counts.
+ *
+ * Compute triangle counts for the entire set of vertices (if @p vertices is std::nullopt) or the
+ * given vertices (@p vertices.has_value() is true).
+ *
+ * @tparam vertex_t Type of vertex identifiers. Needs to be an integral type.
+ * @tparam edge_t Type of edge identifiers. Needs to be an integral type.
+ * @tparam weight_t Type of edge weights. Needs to be a floating point type.
+ * @tparam multi_gpu Flag indicating whether template instantiation should target single-GPU (false)
+ * @param handle RAFT handle object to encapsulate resources (e.g. CUDA stream, communicator, and
+ * handles to various CUDA libraries) to run graph algorithms.
+ * @param graph_view Graph view object.
+ * @param vertices Vertices to compute triangle counts. If @p vertices.has_value() is false, compute
+ * triangle counts for the entire set of vertices.
+ * @param counts Output triangle count array. The size of the array should be the local vertex
+ * partition range size (if @p vertices is std::nullopt) or the size of @p vertices (if @p
+ * vertices.has_value() is true).
+ * @param do_expensive_check A flag to run expensive checks for input arguments (if set to `true`).
+ */
+template <typename vertex_t, typename edge_t, typename weight_t, bool multi_gpu>
+void triangle_counts(raft::handle_t const& handle,
+                     graph_view_t<vertex_t, edge_t, weight_t, false, multi_gpu> const& graph_view,
+                     std::optional<raft::device_span<vertex_t>> vertices,
+                     raft::device_span<edge_t> counts,
+                     bool do_expensive_check = false);
+
 }  // namespace cugraph

cpp/src/community/triangle_counts_impl.cuh

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2022, NVIDIA CORPORATION.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#pragma once
+
+#include <cugraph/algorithms.hpp>
+
+namespace cugraph {
+
+template <typename vertex_t, typename edge_t, typename weight_t, bool multi_gpu>
+void triangle_counts(raft::handle_t const& handle,
+                     graph_view_t<vertex_t, edge_t, weight_t, false, multi_gpu> const& graph_view,
+                     std::optional<raft::device_span<vertex_t>> vertices,
+                     raft::device_span<edge_t> counts,
+                     bool do_expensive_check)
+{
+  CUGRAPH_FAIL("unimplemented.");
+  return;
+}
+
+}  // namespace cugraph

cpp/src/community/triangle_counts_mg.cu

@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2022, NVIDIA CORPORATION.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <community/triangle_counts_impl.cuh>
+
+namespace cugraph {
+
+void triangle_counts(raft::handle_t const& handle,
+                     graph_view_t<int32_t, int32_t, float, false, true> const& graph_view,
+                     std::optional<raft::device_span<int32_t>> vertices,
+                     raft::device_span<int32_t> counts,
+                     bool do_expensive_check);
+
+void triangle_counts(raft::handle_t const& handle,
+                     graph_view_t<int32_t, int32_t, double, false, true> const& graph_view,
+                     std::optional<raft::device_span<int32_t>> vertices,
+                     raft::device_span<int32_t> counts,
+                     bool do_expensive_check);
+
+void triangle_counts(raft::handle_t const& handle,
+                     graph_view_t<int32_t, int64_t, float, false, true> const& graph_view,
+                     std::optional<raft::device_span<int32_t>> vertices,
+                     raft::device_span<int64_t> counts,
+                     bool do_expensive_check);
+
+void triangle_counts(raft::handle_t const& handle,
+                     graph_view_t<int32_t, int64_t, double, false, true> const& graph_view,
+                     std::optional<raft::device_span<int32_t>> vertices,
+                     raft::device_span<int64_t> counts,
+                     bool do_expensive_check);
+
+void triangle_counts(raft::handle_t const& handle,
+                     graph_view_t<int64_t, int64_t, float, false, true> const& graph_view,
+                     std::optional<raft::device_span<int64_t>> vertices,
+                     raft::device_span<int64_t> counts,
+                     bool do_expensive_check);
+
+void triangle_counts(raft::handle_t const& handle,
+                     graph_view_t<int64_t, int64_t, double, false, true> const& graph_view,
+                     std::optional<raft::device_span<int64_t>> vertices,
+                     raft::device_span<int64_t> counts,
+                     bool do_expensive_check);
+
+}  // namespace cugraph

cpp/src/community/triangle_counts_sg.cu

@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2022, NVIDIA CORPORATION.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <community/triangle_counts_impl.cuh>
+
+namespace cugraph {
+
+void triangle_counts(raft::handle_t const& handle,
+                     graph_view_t<int32_t, int32_t, float, false, false> const& graph_view,
+                     std::optional<raft::device_span<int32_t>> vertices,
+                     raft::device_span<int32_t> counts,
+                     bool do_expensive_check);
+
+void triangle_counts(raft::handle_t const& handle,
+                     graph_view_t<int32_t, int32_t, double, false, false> const& graph_view,
+                     std::optional<raft::device_span<int32_t>> vertices,
+                     raft::device_span<int32_t> counts,
+                     bool do_expensive_check);
+
+void triangle_counts(raft::handle_t const& handle,
+                     graph_view_t<int32_t, int64_t, float, false, false> const& graph_view,
+                     std::optional<raft::device_span<int32_t>> vertices,
+                     raft::device_span<int64_t> counts,
+                     bool do_expensive_check);
+
+void triangle_counts(raft::handle_t const& handle,
+                     graph_view_t<int32_t, int64_t, double, false, false> const& graph_view,
+                     std::optional<raft::device_span<int32_t>> vertices,
+                     raft::device_span<int64_t> counts,
+                     bool do_expensive_check);
+
+void triangle_counts(raft::handle_t const& handle,
+                     graph_view_t<int64_t, int64_t, float, false, false> const& graph_view,
+                     std::optional<raft::device_span<int64_t>> vertices,
+                     raft::device_span<int64_t> counts,
+                     bool do_expensive_check);
+
+void triangle_counts(raft::handle_t const& handle,
+                     graph_view_t<int64_t, int64_t, double, false, false> const& graph_view,
+                     std::optional<raft::device_span<int64_t>> vertices,
+                     raft::device_span<int64_t> counts,
+                     bool do_expensive_check);
+
+}  // namespace cugraph