From 61838d14d1b5f46a162f8d6a12b7e41bcf0ae949 Mon Sep 17 00:00:00 2001
From: Boris MUZELLEC <boris.muzellec@owkin.com>
Date: Tue, 1 Aug 2023 16:53:11 +0200
Subject: [PATCH] fix: support coeff=None for continuous factors in
 lfc_shrink()

---
 pydeseq2/ds.py | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/pydeseq2/ds.py b/pydeseq2/ds.py
index e3b80ed2..4e772617 100644
--- a/pydeseq2/ds.py
+++ b/pydeseq2/ds.py
@@ -304,7 +304,14 @@ def lfc_shrink(self, coeff: Optional[str] = None) -> None:
             (default: ``None``).
         """
 
-        contrast_level = f"{self.contrast[0]}_{self.contrast[1]}_vs_{self.contrast[2]}"
+        if self.contrast[1] == self.contrast[2] == "":
+            # The factor being tested is continuous
+            contrast_level = self.contrast[0]
+        else:
+            # The factor being tested is categorical
+            contrast_level = (
+                f"{self.contrast[0]}_{self.contrast[1]}_vs_{self.contrast[2]}"
+            )
 
         if coeff is not None:
             if coeff not in self.LFC.columns: