# state space implementation using DLM FKF

state space model , I am trying to implement is as follows $$y_t= CY + FF* X_t + Ve_t$$ $$(X_t-m0)= GG (X_{t-1}-m0) +W\eta_t$$

In DLM I am using following modification(because DLM does not allow intercept in measurement and transition equation)

mod= build(param) #creates DLM objects with some additional objects
adj= mod$FF%*%mod$m0+ mod$CY data= t(apply(data_full,1,function(x) x-adj)) # adjust Y variable for the intercept term mod$m0=0 # now latent factor will have zero mean
dlmLL(data,mod )


Now I am trying to implement the same using fkf package

mod= build(param)
mod$CX= (I-mod$GG)%*%mod$m0 ans <- fkf(a0 = mod$m0, P0 = mod$C0, dt = mod$CX, ct = mod$CY, Tt = mod$GG,
Zt = mod$FF, HHt = mod$W, GGt = mod$V, yt = t(data_full)) ans$logLik


are both the approaches right? If yes, then Why I am getting different likelihood values using different packages, and which one should be preferred