From 61df4e01dfebc7614284351a338ac70310c92a22 Mon Sep 17 00:00:00 2001
From: Emmanuel Giner <giner.emmanuel@gmail.com>
Date: Thu, 30 Apr 2020 19:35:21 +0200
Subject: [PATCH] added shank

---
 src/utils/shank.irp.f | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/utils/shank.irp.f b/src/utils/shank.irp.f
index 4ec10bbe..238538f3 100644
--- a/src/utils/shank.irp.f
+++ b/src/utils/shank.irp.f
@@ -34,6 +34,12 @@ double precision function shank_function(array,i,n)
  double precision :: b_n, b_n1
  b_n = array(i) - array(i-1)
  b_n1 = array(i+1) - array(i)
- shank_function = array(i+1) - b_n1*b_n1/(b_n1-b_n)
+ if(dabs(b_n1-b_n).lt.1.d-12)then
+  shank_function = array(i+1)
+ else
+  shank_function = array(i+1) - b_n1*b_n1/(b_n1-b_n)
+ endif
+
 end
 
+