-------- general spatial model estimation functions --------
f2_sac : evaluates log-likelihood for ML values general spatial model f_sac : evaluates log-likelihood for general spatial model prt_sac : Prints output using sac model results structures sac : computes general Spatial Model estimates sac_d : An example of using sac() on a small dataset sac_d2 : An example of using sac() on a large data set sac_dnew : An example of using sac() on a small dataset