expandF: Expand F
In SpatioTemporal: Spatio-Temporal Model Estimation

Description Usage Arguments Value Author(s) See Also Examples

Expands the temporal trends in F to a full matrix (with lots of zeros). Mainly used for testing, and illustration in examples.

1	expandF(F, loc.ind, n.loc = max(loc.ind), sparse = TRUE)

`F`	A (number of obs.) - by - (number of temporal trends) matrix containing the temporal trends. Usually `mesa.model$F`, where `mesa.model` is obtained from `createSTmodel`.
`loc.ind`	A vector indicating which location each row in `F` corresponds to, usually `mesa.model$obs$idx`.
`n.loc`	Number of locations.
`sparse`	Should the returned matrix be sparse (uses the Matrix-package, see `sparseMatrix`)

Returns the expanded F, a dim(F)[1]-by-n.loc*dim(F)[2] matrix

Johan Lindstrom and Adam Szpiro

Other temporal trend functions: calc.FXtF2, calc.FX, calc.tFXF, calc.tFX

##create a trend
trend <- cbind(1:5,sin(1:5))
##an index of locations
idx <- c(rep(1:3,3),1:2,2:3)
##a list of time points for each location/observation
T <- c(rep(1:3,each=3),4,4,5,5)

##expand the F matrix to match the locations/times in idx/T.
F <- trend[T,]

##compute the expanded matrix
expandF(F, idx)

##compute the expanded matrix, assuming additional locations
expandF(F, idx, 5)

##or as a full matrix
expandF(F, idx, 5, sparse=FALSE)