pedometrics (version 0.6-3)

vgmLags: Lag-distance classes for variogram estimation

Description

Computation of lag-distance classes for varioram estimation.

Usage

vgmLags(obj, n = 7, type = "exp", cutoff = 0.5, base = 2,
  zero = 0.001)

Arguments

obj

Data frame or matrix; the x and y coordinates (the coordinates must be projected).

n

Integer value; the number of lag-distace classes. Defaults to n = 7.

type

Caracter value; the type of lag-distance classes, with options equi (equidistant) and exp (exponential). Defaults to type = "exp".

cutoff

Numeric value; the fraction of the maximum pair-wise sepation distances that should be used to compute the lag-distance classes. Defaults to cutoff = 0.5.

base

Numeric value; the base of the exponential expression used to create exponentially spaced lag-distance classes. Used only when type = "exp". Defaults to base = 2.

zero

Numeric value; the minimum pair-wise separation distance that should be used to compute the lag-distance classes. Defaults to zero = 0.0001.

Value

• Vector of numeric values with the breaks of the lag-distance classes.

concept

variogram

References

Truong, P. N.; Heuvelink, G. B. M.; Gosling, J. P. Web-based tool for expert elicitation of the variogram. Computers and Geosciences. v. 51, p. 390-399, 2013.

See Also

optimPPL

Examples

require(sp)
data(meuse.grid)
id <- sample(nrow(meuse.grid), 100)
obj <- meuse.grid[id, 1:2]
vgmLags(obj)