# plot.ps2dnormal: Plotting function for 'ps2DNormal' In JOPS: Practical Smoothing with P-Splines

 plot.ps2dnormal R Documentation

## Plotting function for `ps2DNormal`

### Description

Plotting function for 2D P-spline smooothing (using `ps2DNormal` with `class ps2dnormal`).

### Usage

``````## S3 method for class 'ps2dnormal'
plot(x, ..., xlab = " ", ylab = " ", Resol = 100)
``````

### Arguments

 `x` the P-spline object, usually from `ps2DNormal`. `...` other parameters. `xlab` label for the x-axis, e.g. "my x" (quotes required). `ylab` label for the y-axis, e.g. "my y" (quotes required). `Resol` resolution for plotting, default `Resol = 100`.

### Value

 `Plot` a plot of the smooth 2D P-spline smooth surface.

### Author(s)

Paul Eilers and Brian Marx

### References

Eilers, P.H.C. and Marx, B.D. (2021). Practical Smoothing, The Joys of P-splines. Cambridge University Press.

Eilers, P.H.C., Marx, B.D., and Durban, M. (2015). Twenty years of P-splines, SORT, 39(2): 149-186.

### Examples

``````library(SemiPar)
library(fields)
library(spam)
library(JOPS)

# Get the data
data(ethanol)
x <- ethanol\$C
y <- ethanol\$E
z <- ethanol\$NOx

# Set parameters for domain
xlo <- 7
xhi <- 19
ylo <- 0.5
yhi <- 1.25

# Set P-spline parameters, fit and compute surface
xpars <- c(xlo, xhi, 10, 3, 3, 1)
ypars <- c(ylo, yhi, 10, 3, 3, 1)
Pars1 <- rbind(xpars, ypars)
fit <- ps2DNormal(cbind(x, y, z), Pars = Pars1)
plot(fit, xlab = "C", ylab = "E")
``````

JOPS documentation built on Sept. 8, 2023, 5:42 p.m.