diff --git a/tsts/apis.py b/tsts/apis.py
index 54f2557..b640598 100644
--- a/tsts/apis.py
+++ b/tsts/apis.py
@@ -35,11 +35,11 @@ def load_sample(
     df = df.fillna(0.0)
     # Take only the values of input & output variables
     if len(in_feats) > 0:
-        df = df[in_feats]
+        df_in = df[in_feats]
     if len(out_feats) > 0:
-        df = df[out_feats]
-    X = torch.tensor(df.values, dtype=torch.float32)
-    y = torch.tensor(df.values, dtype=torch.float32)
+        df_out = df[out_feats]
+    X = torch.tensor(df_in.values, dtype=torch.float32)
+    y = torch.tensor(df_out.values, dtype=torch.float32)
     return (X, y)