Update src/array_api_extra/_delegation.py

Co-authored-by: Guido Imperiale <crusaderky@gmail.com>

Author: NeilGirdhar

src/array_api_extra/_delegation.py

@@ -169,7 +169,7 @@ def one_hot(
         msg = "x must have an integral dtype."
         raise TypeError(msg)
     if dtype is None:
-        dtype = xp.empty(()).dtype  # Default float dtype
+        dtype = xp.__array_namespace_info__().default_dtypes(device=get_device(x))["real floating"]
     # Delegate where possible.
     if is_jax_namespace(xp):
         assert is_jax_array(x)