initialize random seed

csrc/cpu/ego_sample_cpu.cpp

@@ -15,6 +15,8 @@ ego_k_hop_sample_adj_cpu(torch::Tensor rowptr, torch::Tensor col,
                          torch::Tensor idx, int64_t depth,
                          int64_t num_neighbors, bool replace) {
 
+  srand(time(NULL) + 1000 * getpid()); // Initialize random seed.
+
   std::vector<torch::Tensor> out_rowptrs(idx.numel() + 1);
   std::vector<torch::Tensor> out_cols(idx.numel());
   std::vector<torch::Tensor> out_n_ids(idx.numel());

csrc/cpu/hgt_sample_cpu.cpp

@@ -101,6 +101,8 @@ hgt_sample_cpu(const c10::Dict<rel_t, torch::Tensor> &colptr_dict,
                const c10::Dict<node_t, vector<int64_t>> &num_samples_dict,
                const int64_t num_hops) {
 
+  srand(time(NULL) + 1000 * getpid()); // Initialize random seed.
+
   // Create a mapping to convert single string relations to edge type triplets:
   unordered_map<rel_t, edge_t> to_edge_type;
   for (const auto &kv : colptr_dict) {

csrc/cpu/neighbor_sample_cpu.cpp

@@ -11,6 +11,8 @@ tuple<torch::Tensor, torch::Tensor, torch::Tensor, torch::Tensor>
 sample(const torch::Tensor &colptr, const torch::Tensor &row,
        const torch::Tensor &input_node, const vector<int64_t> num_neighbors) {
 
+  srand(time(NULL) + 1000 * getpid()); // Initialize random seed.
+
   // Initialize some data structures for the sampling process:
   vector<int64_t> samples;
   unordered_map<int64_t, int64_t> to_local_node;
@@ -121,6 +123,8 @@ hetero_sample(const vector<node_t> &node_types,
               const c10::Dict<rel_t, vector<int64_t>> &num_neighbors_dict,
               const int64_t num_hops) {
 
+  srand(time(NULL) + 1000 * getpid()); // Initialize random seed.
+
   // Create a mapping to convert single string relations to edge type triplets:
   unordered_map<rel_t, edge_t> to_edge_type;
   for (const auto &k : edge_types)

csrc/cpu/sample_cpu.cpp

@@ -11,6 +11,8 @@ sample_adj_cpu(torch::Tensor rowptr, torch::Tensor col, torch::Tensor idx,
   CHECK_CPU(idx);
   CHECK_INPUT(idx.dim() == 1);
 
+  srand(time(NULL) + 1000 * getpid()); // Initialize random seed.
+
   auto rowptr_data = rowptr.data_ptr<int64_t>();
   auto col_data = col.data_ptr<int64_t>();
   auto idx_data = idx.data_ptr<int64_t>();