function [k,s] = kfilter(A,C,V1,V2,V12) function [k,s] = kfilter(A,C,V1,V2,V12) KFILTER can have arguments: (A,C,V1,V2) if there are no cross products, V12=0. KFILTER calculates the kalman gain, k, and the stationary -functi