diff --git a/treescope/external/torch_support.py b/treescope/external/torch_support.py
index 0b00e70..0da96d2 100644
--- a/treescope/external/torch_support.py
+++ b/treescope/external/torch_support.py
@@ -189,7 +189,8 @@ def get_array_summary(self, array: torch.Tensor, fast: bool) -> str:
       output_parts.append("(" + ", ".join(name_parts) + ")")
 
     # Drop axis names.
-    array = array.rename(None)
+    if any(name is not None for name in array.names):
+      array = array.rename(None)
     size = np.prod(array.shape)
     if size > 0 and size < 100_000 and not fast:
       is_floating = array.dtype.is_floating_point
@@ -230,11 +231,11 @@ def get_array_summary(self, array: torch.Tensor, fast: bool) -> str:
         if ct_nan:
           output_parts.append(f" nan:{ct_nan:_d}")
 
-        ct_inf = torch.count_nonzero(torch.isposinf(array))
+        ct_inf = torch.count_nonzero(array == torch.inf)
         if ct_inf:
           output_parts.append(f" inf:{ct_inf:_d}")
 
-        ct_neginf = torch.count_nonzero(torch.isneginf(array))
+        ct_neginf = torch.count_nonzero(array == -torch.inf)
         if ct_neginf:
           output_parts.append(f" -inf:{ct_neginf:_d}")