fix neighbor sampling

csrc/cpu/sampler_cpu.cpp

@@ -15,9 +15,10 @@ torch::Tensor neighbor_sampler_cpu(torch::Tensor start, torch::Tensor rowptr,
     auto num_neighbors = row_end - row_start;
 
     int64_t size = count;
-    if (count < 1) {
+    if (count < 1)
       size = int64_t(ceil(factor * float(num_neighbors)));
-    }
+    if (size > num_neighbors)
+      size = num_neighbors;
 
     // If the number of neighbors is approximately equal to the number of
     // neighbors which are requested, we use `randperm` to sample without
@@ -26,16 +27,16 @@ torch::Tensor neighbor_sampler_cpu(torch::Tensor start, torch::Tensor rowptr,
     std::unordered_set<int64_t> set;
     if (size < 0.7 * float(num_neighbors)) {
       while (int64_t(set.size()) < size) {
-        int64_t sample = (rand() % num_neighbors) + row_start;
-        set.insert(sample);
+        int64_t sample = rand() % num_neighbors;
+        set.insert(sample + row_start);
       }
       std::vector<int64_t> v(set.begin(), set.end());
       e_ids.insert(e_ids.end(), v.begin(), v.end());
     } else {
-      auto sample = at::randperm(num_neighbors, start.options()) + row_start;
+      auto sample = torch::randperm(num_neighbors, start.options());
       auto sample_data = sample.data_ptr<int64_t>();
       for (auto j = 0; j < size; j++) {
-        e_ids.push_back(sample_data[j]);
+        e_ids.push_back(sample_data[j] + row_start);
       }
     }
   }

setup.py

@@ -63,7 +63,7 @@ tests_require = ['pytest', 'pytest-cov']
 
 setup(
     name='torch_cluster',
-    version='1.5.1',
+    version='1.5.2',
     author='Matthias Fey',
     author_email='matthias.fey@tu-dortmund.de',
     url='https://github.com/rusty1s/pytorch_cluster',

torch_cluster/__init__.py

@@ -3,7 +3,7 @@ import os.path as osp
 
 import torch
 
-__version__ = '1.5.1'
+__version__ = '1.5.2'
 expected_torch_version = (1, 4)
 
 try: