From 27923f50100933ad2cae8c5ac40aae6291ef76d1 Mon Sep 17 00:00:00 2001
From: QuanSheng Wu <quansheng.wu@iphy.ac.cn>
Date: Thu, 24 Feb 2022 11:04:07 +0800
Subject: [PATCH] fixed a bug in AHC calculation when there are degenerate
 bands

---
 src/berrycurvature.f90 | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/berrycurvature.f90 b/src/berrycurvature.f90
index 423c084c..ab2fc4cc 100644
--- a/src/berrycurvature.f90
+++ b/src/berrycurvature.f90
@@ -451,7 +451,9 @@ subroutine get_Dmn_Ham(W, velocity_Ham, Dmn_Ham)
      do i=1, 3
         do n=1, Num_wann
            do m=1, Num_wann
-              Dmn_Ham(m,n,i)=velocity_Ham(m,n,i)/(W(n)-W(m))
+              if (abs(W(n)-W(m))>eps12) then
+                 Dmn_Ham(m,n,i)=velocity_Ham(m,n,i)/(W(n)-W(m))
+              endif
            enddo
            Dmn_Ham(n, n, i)=zzero
         enddo