From 89e186ca3b12af8782438284b77e001eb05912ad Mon Sep 17 00:00:00 2001
From: teobucci <teobucci8@gmail.com>
Date: Sun, 25 Feb 2024 15:51:29 +0100
Subject: [PATCH] Fix check that var_names is not None before checking its
 length

---
 src/tefs/core.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/tefs/core.py b/src/tefs/core.py
index 835fb53..ee98862 100644
--- a/src/tefs/core.py
+++ b/src/tefs/core.py
@@ -379,7 +379,7 @@ def fs(
     if direction not in ['forward', 'backward']:
         raise ValueError("direction must be either 'forward' or 'backward'")
     
-    if not len(var_names) == features.shape[1]:
+    if var_names and not len(var_names) == features.shape[1]:
         raise ValueError("var_names must have the same length as the number of features")
 
     # Prepare common arguments for both functions