diff --git a/lib/simd/Grid_avx.h b/lib/simd/Grid_avx.h
index 2dc38cca..a00e29eb 100644
--- a/lib/simd/Grid_avx.h
+++ b/lib/simd/Grid_avx.h
@@ -4,7 +4,7 @@
 
   Using intrinsics
 */
-// Time-stamp: <2015-06-09 14:26:59 neo>
+// Time-stamp: <2015-06-16 23:30:41 neo>
 //----------------------------------------------------------------------
 
 #include <immintrin.h>
@@ -248,7 +248,7 @@ namespace Optimization {
       return _mm256_set_m128i(a1,a0);
 #endif
 #if defined (AVX2)
-      return _mm256_mul_epi32(a,b);
+      return _mm256_mullo_epi32(a,b);
 #endif
 
     }
diff --git a/lib/simd/Grid_sse4.h b/lib/simd/Grid_sse4.h
index 3a54c0b3..62516201 100644
--- a/lib/simd/Grid_sse4.h
+++ b/lib/simd/Grid_sse4.h
@@ -4,7 +4,7 @@
 
   Using intrinsics
 */
-// Time-stamp: <2015-06-09 14:24:01 neo>
+// Time-stamp: <2015-06-16 23:27:54 neo>
 //----------------------------------------------------------------------
 
 #include <pmmintrin.h>
@@ -97,7 +97,7 @@ namespace Optimization {
     }
     // Integer
     inline __m128i operator()(Integer *a){
-      return _mm_set_epi32(a[0],a[1],a[2],a[3]);
+      return _mm_set_epi32(a[3],a[2],a[1],a[0]);
     }
 
 
@@ -181,7 +181,7 @@ namespace Optimization {
     }
     // Integer
     inline __m128i operator()(__m128i a, __m128i b){
-      return _mm_mul_epi32(a,b);
+      return _mm_mullo_epi32(a,b);
     }
   };
 
diff --git a/lib/tensors/Tensor_Ta.h b/lib/tensors/Tensor_Ta.h
index f06dbf04..0eea1e6d 100644
--- a/lib/tensors/Tensor_Ta.h
+++ b/lib/tensors/Tensor_Ta.h
@@ -63,26 +63,70 @@ namespace Grid {
       for(int c1=0;c1<N;c1++){
 	nrm = 0.0; 
 	for(int c2=0;c2<N;c2++)
-	  nrm = real(innerProduct(ret._internal[c1][c2],ret._internal[c1][c2]));
+	  nrm += real(innerProduct(ret._internal[c1][c2],ret._internal[c1][c2]));
 	nrm = 1.0/sqrt(nrm);
+	std::cout << "norm : "<< nrm << "\n";
 	for(int c2=0;c2<N;c2++)
 	  ret._internal[c1][c2]*= nrm;
       
 	for (int b=c1+1; b<N; ++b){
 	  decltype(ret._internal[b][b]*ret._internal[b][b]) pr = 0.0;
 	  for(int c=0; c<N; ++c)
-	    pr += ret._internal[c1][c]*ret._internal[b][c];
+	    pr += conjugate(ret._internal[c1][c])*ret._internal[b][c];
 	  
+	  std::cout << "pr : "<< pr << "\n";
 	  for(int c=0; c<N; ++c){
 	    ret._internal[b][c] -= pr * ret._internal[c1][c];
 	  }
 	}
 	  
       }
+      // assuming the determinant is ok
       return ret;
     }
 
 
+  /////////////////////////////////////////////// 
+  // Determinant function for scalar, vector, matrix
+  /////////////////////////////////////////////// 
+  inline ComplexF Determinant( const ComplexF &arg){    return arg;}
+  inline ComplexD Determinant( const ComplexD &arg){    return arg;}
+  inline RealF Determinant( const RealF &arg){    return arg;}
+  inline RealD Determinant( const RealD &arg){    return arg;}
+
+  template<class vtype> inline auto Determinant(const iScalar<vtype>&r) -> iScalar<decltype(Determinant(r._internal))>
+    {
+      iScalar<decltype(Determinant(r._internal))> ret;
+      ret._internal = Determinant(r._internal);
+      return ret;
+    }
+
+  template<class vtype,int N, typename std::enable_if< GridTypeMapper<vtype>::TensorLevel == 0 >::type * =nullptr> 
+    inline iScalar<vtype> Determinant(const iMatrix<vtype,N> &arg)
+    {
+      iMatrix<vtype,N> ret(arg);
+      iScalar<vtype> det = vtype(1.0);
+      /* Conversion of matrix to upper triangular */
+      for(int i = 0; i < N; i++){
+        for(int j = 0; j < N; j++){
+	  if(j>i){
+	    vtype ratio = ret._internal[j][i]/ret._internal[i][i];
+	    for(int k = 0; k < N; k++){
+	      ret._internal[j][k] -= ratio * ret._internal[i][k];
+	    }
+	  }
+        }
+      }      
+
+      for(int i = 0; i < N; i++)
+	det *= ret._internal[i][i];   
+
+      return det;
+    }
+
+
+
+
   /////////////////////////////////////////////// 
   // Exponentiate function for scalar, vector, matrix
   /////////////////////////////////////////////// 
diff --git a/lib/tensors/Tensor_extract_merge.h b/lib/tensors/Tensor_extract_merge.h
index cea9bb64..21ffd778 100644
--- a/lib/tensors/Tensor_extract_merge.h
+++ b/lib/tensors/Tensor_extract_merge.h
@@ -57,7 +57,7 @@ inline void extract(typename std::enable_if<!isGridTensor<vsimd>::value, const v
     extracted[i]=buf[i*s];
     for(int ii=1;ii<s;ii++){
       if ( buf[i*s]!=buf[i*s+ii] ){
-	std::cout << " SIMD extract failure splat="<<s<<" ii "<<ii<<" " <<Nextr<<" "<< Nsimd<<" "<<std::endl;
+	std::cout << " SIMD extract failure splat = "<<s<<" ii "<<ii<<" " <<Nextr<<" "<< Nsimd<<" "<<std::endl;
 	for(int vv=0;vv<Nsimd;vv++) {
 	  std::cout<< buf[vv]<<" ";
 	}
diff --git a/tests/Make.inc b/tests/Make.inc
index d04bf0ac..41d4ab8f 100644
--- a/tests/Make.inc
+++ b/tests/Make.inc
@@ -1,5 +1,5 @@
 
-bin_PROGRAMS = Test_GaugeAction Test_Metropolis Test_cayley_cg Test_cayley_coarsen_support Test_cayley_even_odd Test_cayley_ldop_cg Test_cayley_ldop_cr Test_cf_coarsen_support Test_cf_cr_unprec Test_contfrac_cg Test_contfrac_even_odd Test_cshift Test_cshift_red_black Test_dwf_cg_prec Test_dwf_cg_schur Test_dwf_cg_unprec Test_dwf_cr_unprec Test_dwf_even_odd Test_gamma Test_lie_generators Test_main Test_multishift_sqrt Test_nersc_io Test_remez Test_rng Test_rng_fixed Test_simd Test_stencil Test_wilson_cg_prec Test_wilson_cg_schur Test_wilson_cg_unprec Test_wilson_cr_unprec Test_wilson_even_odd
+bin_PROGRAMS = Test_GaugeAction Test_Metropolis Test_cayley_cg Test_cayley_coarsen_support Test_cayley_even_odd Test_cayley_ldop_cg Test_cayley_ldop_cr Test_cf_coarsen_support Test_cf_cr_unprec Test_contfrac_cg Test_contfrac_even_odd Test_cshift Test_cshift_red_black Test_dwf_cg_prec Test_dwf_cg_schur Test_dwf_cg_unprec Test_dwf_cr_unprec Test_dwf_even_odd Test_gamma Test_lie_generators Test_main Test_multishift_sqrt Test_nersc_io Test_quenched_update Test_remez Test_rng Test_rng_fixed Test_simd Test_stencil Test_wilson_cg_prec Test_wilson_cg_schur Test_wilson_cg_unprec Test_wilson_cr_unprec Test_wilson_even_odd
 
 
 Test_GaugeAction_SOURCES=Test_GaugeAction.cc
@@ -94,6 +94,10 @@ Test_nersc_io_SOURCES=Test_nersc_io.cc
 Test_nersc_io_LDADD=-lGrid
 
 
+Test_quenched_update_SOURCES=Test_quenched_update.cc
+Test_quenched_update_LDADD=-lGrid
+
+
 Test_remez_SOURCES=Test_remez.cc
 Test_remez_LDADD=-lGrid
 
diff --git a/tests/Test_main.cc b/tests/Test_main.cc
index daa6c3aa..9db38059 100644
--- a/tests/Test_main.cc
+++ b/tests/Test_main.cc
@@ -1,9 +1,5 @@
 #include "Grid.h"
 
-//DEBUG
-#ifdef SSE4
-#include "simd/Grid_vector_types.h"
-#endif
 
 using namespace std;
 using namespace Grid;
@@ -216,16 +212,27 @@ int main (int argc, char ** argv)
     scm=transposeIndex<1>(scm);
     
    
-    //random(SerialRNG, cm);
+    random(SerialRNG, cm);
+    std::cout << cm << std::endl;
+
+    //cm = Ta(cm);
+    //TComplex tracecm= trace(cm);      
     //std::cout << cm << std::endl;
 
-    cm = Ta(cm);
-    //TComplex tracecm= trace(cm);      
-    //std::cout << cm << "  "<< tracecm << std::endl;
-
     cm = ProjectOnGroup(cm);
+    std::cout << cm << "  " << std::endl;
+    cm = ProjectOnGroup(cm);
+    std::cout << cm << "  " << std::endl;
 
+
+    TComplex det = Determinant(cm);
+    
+    std::cout << "determinant: " << det <<  std::endl;
     cm = Exponentiate(cm, 1.0, 10);
+    std::cout << cm << "  " << std::endl;
+    det = Determinant(cm);
+    std::cout << "determinant: " << det <<  std::endl;
+
 
 //    Foo = Foo+scalar; // LatticeColourMatrix+Scalar
 //    Foo = Foo*scalar; // LatticeColourMatrix*Scalar
@@ -296,10 +303,12 @@ int main (int argc, char ** argv)
       LatticeInteger coor(&Fine);
       LatticeCoordinate(coor,d);
       lex = lex + coor*mm[d];
+      
     }
 
     Bar = zero;
     Bar = where(lex<Integer(10),Foo,Bar);
+    cout << "peeking sites..\n";
     {
       std::vector<int> coor(4);
       for(coor[3]=0;coor[3]<latt_size[3]/mpi_layout[3];coor[3]++){