Computes the cross covariance matrix between two sets of locations for a spatial random process with a given covariance structure. Typically the two sets are a learning set and a test set.
covMat1Mat2(object, X1, X2, nugget.flag=FALSE)
an object specifying the covariance structure.
a matrix whose rows represent the locations of a first set (for instance a set of learning points).
a matrix whose rows represent the locations of a second set (for instance a set of test points).
an optional boolean. If
TRUE, the covariance between 2 equal locations takes into account the nugget effect (if any). Locations are considered equal if their euclidian distance is inferior to
1e-15. Default is
a matrix of size
(nb of rows of X1 * nb of rows of X2) whose element
(i1,i2) is equal to the covariance between the locations specified by row
X1 and row