vmap.grid {RGeostats}  R Documentation 
Calculate the Variogram Map for a set of variables in a Grid Data Base
vmap.grid(dbgrid, dbmap=NA, nx = 10, ny = 10, nz=10, calcul="vg",flag.fft=TRUE, radix = NA, modify.target = db.locmod())
dbgrid 
The 
dbmap 
The 
nx 
Gives the dimension of the Variogram Map along the first axis (2*nx+1) 
ny 
Gives the dimension of the Variogram Map along the second axis (2*ny+1) 
nz 
Gives the dimension of the Variogram Map along the third axis (2*nz+1) 
calcul 
Character string giving the type of structure to compute:

flag.fft 
When TRUE, launch the calculation using the specific calculations using FFT tgransforms (only available for 2D grids) 
radix 
Radix of the name given to the variables stored in the Variogram Map Grid 
modify.target 
Decides whether or not the newly created variables will have their
locator defined or not. For more information, see 
The output consists of a new Grid Data Base with several new variables:
VMAP 
Variables containing the variogram map results 
NB 
Variables containing the number of pairs 