diff --git a/python/swiftest/swiftest/init_cond.py b/python/swiftest/swiftest/init_cond.py
index 02ff6f8e1..6f513b274 100644
--- a/python/swiftest/swiftest/init_cond.py
+++ b/python/swiftest/swiftest/init_cond.py
@@ -286,7 +286,7 @@ def vec2xr(param: Dict, **kwargs: Any):
         if "rot" not in kwargs and "Gmass" in kwargs:
             kwargs['rot'] = np.zeros((len(kwargs['Gmass']),3))
         if "Ip" not in kwargs and "Gmass" in kwargs:
-            kwargs['Ip'] = np.full_like(kwargs['Gmass'], 0.4)
+            kwargs['Ip'] = np.full((len(kwargs['Gmass']),3), 0.4)
 
     if "time" not in kwargs:
         kwargs["time"] = np.array([0.0])