spatial (version 7.3-18)

predict.trls: Predict method for trend surface fits

Description

Predicted values based on trend surface model object

Usage

# S3 method for trls
predict(object, x, y, ...)

Value

predict.trls produces a vector of predictions corresponding to the prediction locations. To display the output with image

or contour, use trmat or convert the returned vector to matrix form.

Arguments

object

Fitted trend surface model object returned by surf.ls

x

Vector of prediction location eastings (x coordinates)

y

Vector of prediction location northings (y coordinates)

...

further arguments passed to or from other methods.

References

Venables, W. N. and Ripley, B. D. (2002) Modern Applied Statistics with S. Fourth edition. Springer.

See Also

surf.ls, trmat

Examples

data(topo, package="MASS")
topo2 <- surf.ls(2, topo)
topo4 <- surf.ls(4, topo)
x <- c(1.78, 2.21)
y <- c(6.15, 6.15)
z2 <- predict(topo2, x, y)
z4 <- predict(topo4, x, y)
cat("2nd order predictions:", z2, "\n4th order predictions:", z4, "\n")