Changes to remove warnings under icc; disambiguate AVX512 from IMCI correctly

and drop swizzles in AVX512. Don't know why these compiled.

lib/algorithms/iterative/MatrixUtils.h

@@ -0,0 +1,48 @@
+#ifndef GRID_MATRIX_UTILS_H
+#define GRID_MATRIX_UTILS_H
+
+namespace Grid {
+
+  namespace MatrixUtils { 
+
+    template<class T> inline void Size(Matrix<T>& A,int &N,int &M){
+      N=A.size(); assert(N>0);
+      M=A[0].size();
+      for(int i=0;i<N;i++){
+	assert(A[i].size()==M);
+      }
+    }
+
+    template<class T> inline void SizeSquare(Matrix<T>& A,int &N)
+    {
+      int M;
+      Size(A,N,M);
+      assert(N==M);
+    }
+
+    template<class T> inline void Fill(Matrix<T>& A,T & val)
+    { 
+      int N,M;
+      Size(A,N,M);
+      for(int i=0;i<N;i++){
+      for(int j=0;j<M;j++){
+	A[i][j]=val;
+      }}
+    }
+    template<class T> inline void Diagonal(Matrix<T>& A,T & val)
+    { 
+      int N;
+      SizeSquare(A,N);
+      for(int i=0;i<N;i++){
+	A[i][i]=val;
+      }
+    }
+    template<class T> inline void Identity(Matrix<T>& A)
+    {
+      Fill(A,0.0);
+      Diagonal(A,1.0);
+    }
+
+  };
+}
+#endif