From a56379c5948381a4261563f560d27993e32bae40 Mon Sep 17 00:00:00 2001
From: =?utf8?q?J=C3=A9r=C3=B4me=20Benoit?= <jerome.benoit@piment-noir.org>
Date: Thu, 19 Feb 2026 01:40:34 +0100
Subject: [PATCH] fix(zigzag): skip minmax normalization with single valid
 value

---
 quickadapter/user_data/strategies/Utils.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/quickadapter/user_data/strategies/Utils.py b/quickadapter/user_data/strategies/Utils.py
index 70327d1..d7292c2 100644
--- a/quickadapter/user_data/strategies/Utils.py
+++ b/quickadapter/user_data/strategies/Utils.py
@@ -1738,7 +1738,8 @@ def zigzag(
 
         arr = np.asarray(values, dtype=float)
         valid_mask = np.isfinite(arr)
-        if not valid_mask.any():
+        n_valid = valid_mask.sum()
+        if n_valid < 2:
             return values
 
         min_val = np.nanmin(arr)
-- 
2.43.0