calc_prec_matrix: Compute n by n covariance matrix W over n grid cells
In mapn/DAbayes: Bayesian Statistical Model for Climate-Change Detection and Attribution

Description Usage Arguments Value Author(s) Examples

This function computes the covariance matrix of the ensemble members for the measured variable, which is a fixed diagonal matrix with diagonal elements equal to the empirical variance of the corresponding ensemble memebers. Further work will allow W to be a more general matrix (e.g., based on a GMRF) with unknown parameters

1	calc_prec_matrix(neighborhood_matrix, gamma)

`neighborhood_matrix`	an n by n neighborhood matrix for n grid cells
`gamma`	a real valued parameter in covariance matrix W

an n by n covariance matrix

Pulong Ma <[email protected]>

n <- 30  # number of grid cells over the globe
neighborhood_matrix <- Matrix::sparseMatrix(1:n, 1:n, x=rep(1,n))
gamma <- 0.1
W <- calc_prec_matrix(neighborhood_matrix, gamma)
Matrix::image(W, xlab="", ylab="", cex=0.5, cex.lab=0.6)