From 056bf6851f64427735c9e1e1d698d3c772149184 Mon Sep 17 00:00:00 2001
From: Martin Stancsics <martin.stancsics@gmail.com>
Date: Thu, 25 Jan 2024 14:27:18 +0100
Subject: [PATCH] Avoid unnecessary work

---
 src/glum/_glm.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/glum/_glm.py b/src/glum/_glm.py
index 43f6516e..33afb37f 100644
--- a/src/glum/_glm.py
+++ b/src/glum/_glm.py
@@ -2711,7 +2711,8 @@ def _set_up_and_check_fit_args(
                 self.feature_dtypes_ = X.dtypes.to_dict()
                 self.has_missing_category_ = {
                     col: (self.cat_missing_method == "convert") and X[col].isna().any()
-                    for col in self.feature_dtypes_.keys()
+                    for col, dtype in self.feature_dtypes_.items()
+                    if isinstance(dtype, pd.CategoricalDtype)
                 }
 
                 if any(X.dtypes == "category"):