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pyg-team · Oct 31, 2023 · cf440e8 · cf440e8
1 parent 2b7c2fb
commit cf440e8
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/pyg_lib/csrc/sampler/cpu/neighbor_kernel.cpp b/pyg_lib/csrc/sampler/cpu/neighbor_kernel.cpp
@@ -224,7 +224,7 @@ class NeighborSampler {
     // Case 2: Multinomial sampling:
     else {
       at::Tensor index;
-      if (replace) {
+      if (replace) { // at::multinomial has good perfomance only when replace=true, e.g. https://github.com/pytorch/pytorch/issues/11931#top
         index = at::multinomial(weight, count, replace);
       }
       else { // An Efficient Algorithm for Biased Sampling: https://utopia.duth.gr/~pefraimi/research/data/2007EncOfAlg.pdf