From 3a7f3cde535759642d9ef14df7fe8dec92f4ca85 Mon Sep 17 00:00:00 2001
From: Artur Glavic <artur.glavic@psi.ch>
Date: Fri, 27 Feb 2026 08:06:16 +0100
Subject: [PATCH] fix sqrt invalid value warning in footprint correction

---
 eos/projection.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/eos/projection.py b/eos/projection.py
index 7f1785c..2cdc50e 100644
--- a/eos/projection.py
+++ b/eos/projection.py
@@ -224,6 +224,7 @@ class LZProjection(ProjectionInterface):
         # do not perform gravity correction for footprint, would require norm detector distance that is unknown here
         fp_corr_lz = np.where(np.absolute(delta_lz+norm.angle)>5e-3,
                               (delta_lz+self.angle)/(delta_lz+norm.angle), np.nan)
+        fp_corr_lz[fp_corr_lz<0] = np.nan
         self.data.mask &=  np.logical_not(np.isnan(fp_corr_lz))
         self.data.norm = norm_lz*fp_corr_lz
         self.norm_monitor = norm.monitor