From 96de1c0bef42ebfdc75b64907f883d2dbb6c7df8 Mon Sep 17 00:00:00 2001
From: conrad <conrad@localhost.localdomain>
Date: Tue, 22 Mar 2022 17:18:23 +1000
Subject: [PATCH] simplifications

---
 include/armadillo_bits/op_inv_spd_bones.hpp |  8 --------
 include/armadillo_bits/op_inv_spd_meat.hpp  | 18 +++++++++++-------
 2 files changed, 11 insertions(+), 15 deletions(-)

diff --git a/include/armadillo_bits/op_inv_spd_bones.hpp b/include/armadillo_bits/op_inv_spd_bones.hpp
index c4f0feff..3e17a9c3 100644
--- a/include/armadillo_bits/op_inv_spd_bones.hpp
+++ b/include/armadillo_bits/op_inv_spd_bones.hpp
@@ -40,14 +40,6 @@ class op_inv_spd_full
   {
   public:
   
-  template<const uword row, const uword col>
-  struct pos
-    {
-    static constexpr uword n2 = row + col*2;
-    static constexpr uword n3 = row + col*3;
-    static constexpr uword n4 = row + col*4;
-    };
-  
   template<typename T1>
   inline static void apply(Mat<typename T1::elem_type>& out, const Op<T1,op_inv_spd_full>& in);
   
diff --git a/include/armadillo_bits/op_inv_spd_meat.hpp b/include/armadillo_bits/op_inv_spd_meat.hpp
index fa703d54..29562453 100644
--- a/include/armadillo_bits/op_inv_spd_meat.hpp
+++ b/include/armadillo_bits/op_inv_spd_meat.hpp
@@ -203,9 +203,9 @@ op_inv_spd_full::apply_tiny_2x2(Mat<eT>& X)
   
   eT* Xm = X.memptr();
   
-  const T a = access::tmp_real(Xm[pos<0,0>::n2]);
-  const T c = access::tmp_real(Xm[pos<1,0>::n2]);
-  const T d = access::tmp_real(Xm[pos<1,1>::n2]);
+  T a = access::tmp_real(Xm[0]);
+  T c = access::tmp_real(Xm[1]);
+  T d = access::tmp_real(Xm[3]);
   
   const T det_val = (a*d - c*c);
   
@@ -218,10 +218,14 @@ op_inv_spd_full::apply_tiny_2x2(Mat<eT>& X)
   // NOTE: since det_min is positive, this also checks whether det_val is positive
   if((det_val < det_min) || (det_val > det_max))  { return false; }
   
-  Xm[pos<0,0>::n2] =  d / det_val;
-  Xm[pos<0,1>::n2] = -c / det_val;
-  Xm[pos<1,0>::n2] = -c / det_val;
-  Xm[pos<1,1>::n2] =  a / det_val;
+  d /= det_val;
+  c /= det_val;
+  a /= det_val;
+  
+  Xm[0] =  d;
+  Xm[1] = -c;
+  Xm[2] = -c;
+  Xm[3] =  a;
   
   return true;
   }