init

FOTF Toolbox/new_inv.m

@@ -0,0 +1,18 @@
+function A2=new_inv(A)
+% new_inv - a simple matrix inverse function
+%
+%    A2=new_inv(A)
+%
+%   A, A2 - the matrix and its inverse
+%
+%   not recommended, try symbolic version for FOTF matrices
+   
+% Copyright (c) Dingyu Xue, Northeastern University, China
+% Last modified 28 March, 2017 
+% Last modified 18 May, 2022 
+   A1=A; [n,~]=size(A); E0=eye(n); aa=[];
+   for i=1:n, ij=1:n; ij=ij(ij~=i); E=eye(n); a0=A1(i,i);
+      aa=[aa,a0]; E(ij,i)=-A1(ij,i)/a0; E0=E*E0; A1=E*A1;
+   end
+   A2=diag(1./aa)*E0;
+end