flow arg for radius

setup.py

@@ -28,7 +28,7 @@
                       ['cuda/rw.cpp', 'cuda/rw_kernel.cu']),
     ]
 
-__version__ = '1.4.1'
+__version__ = '1.4.2'
 url = 'https://github.com/rusty1s/pytorch_cluster'
 
 install_requires = ['scipy']

test/test_knn.py

@@ -45,12 +45,10 @@ def test_knn_graph(dtype, device):
 
     row, col = knn_graph(x, k=2, flow='target_to_source')
     col = col.view(-1, 2).sort(dim=-1)[0].view(-1)
-
     assert row.tolist() == [0, 0, 1, 1, 2, 2, 3, 3]
     assert col.tolist() == [1, 3, 0, 2, 1, 3, 0, 2]
 
     row, col = knn_graph(x, k=2, flow='source_to_target')
     row = row.view(-1, 2).sort(dim=-1)[0].view(-1)
-
     assert row.tolist() == [1, 3, 0, 2, 1, 3, 0, 2]
     assert col.tolist() == [0, 0, 1, 1, 2, 2, 3, 3]

test/test_radius.py

@@ -47,6 +47,12 @@ def test_radius_graph(dtype, device):
         [+1, -1],
     ], dtype, device)
 
-    out = radius_graph(x, r=2)
-    assert coalesce(out).tolist() == [[0, 0, 1, 1, 2, 2, 3, 3],
-                                      [1, 3, 0, 2, 1, 3, 0, 2]]
+    row, col = radius_graph(x, r=2, flow='target_to_source')
+    col = col.view(-1, 2).sort(dim=-1)[0].view(-1)
+    assert row.tolist() == [0, 0, 1, 1, 2, 2, 3, 3]
+    assert col.tolist() == [1, 3, 0, 2, 1, 3, 0, 2]
+
+    row, col = radius_graph(x, r=2, flow='source_to_target')
+    row = row.view(-1, 2).sort(dim=-1)[0].view(-1)
+    assert row.tolist() == [1, 3, 0, 2, 1, 3, 0, 2]
+    assert col.tolist() == [0, 0, 1, 1, 2, 2, 3, 3]

torch_cluster/__init__.py

@@ -7,7 +7,7 @@
 from .sampler import neighbor_sampler
 from .rw import random_walk
 
-__version__ = '1.4.1'
+__version__ = '1.4.2'
 
 __all__ = [
     'graclus_cluster',

torch_cluster/radius.py

@@ -73,7 +73,12 @@ def radius(x, y, r, batch_x=None, batch_y=None, max_num_neighbors=32):
     return torch.stack([row[mask], col[mask]], dim=0)
 
 
-def radius_graph(x, r, batch=None, loop=False, max_num_neighbors=32):
+def radius_graph(x,
+                 r,
+                 batch=None,
+                 loop=False,
+                 max_num_neighbors=32,
+                 flow='source_to_target'):
     r"""Computes graph edges to all points within a given distance.
 
     Args:
@@ -87,6 +92,9 @@ def radius_graph(x, r, batch=None, loop=False, max_num_neighbors=32):
             self-loops. (default: :obj:`False`)
         max_num_neighbors (int, optional): The maximum number of neighbors to
             return for each element in :obj:`y`. (default: :obj:`32`)
+        flow (string, optional): The flow direction when using in combination
+            with message passing (:obj:`"source_to_target"` or
+            :obj:`"target_to_source"`). (default: :obj:`"source_to_target"`)
 
     :rtype: :class:`LongTensor`
 
@@ -102,11 +110,10 @@ def radius_graph(x, r, batch=None, loop=False, max_num_neighbors=32):
         >>> edge_index = radius_graph(x, r=1.5, batch=batch, loop=False)
     """
 
-    edge_index = radius(x, x, r, batch, batch, max_num_neighbors + 1)
-    row, col = edge_index
+    assert flow in ['source_to_target', 'target_to_source']
+    row, col = radius(x, x, r, batch, batch, max_num_neighbors + 1)
+    row, col = (col, row) if flow == 'source_to_target' else (row, col)
     if not loop:
-        row, col = edge_index
         mask = row != col
         row, col = row[mask], col[mask]
-        edge_index = torch.stack([row, col], dim=0)
-    return edge_index
+    return torch.stack([row, col], dim=0)