cleveland.soil {agridat} R Documentation

## Soil resistivity in a field

### Description

Soil resistivity in a field

### Format

A data frame with 8641 observations on the following 5 variables.

`northing`

y ordinate

`easting`

x ordinate

`resistivity`

Soil resistivity, ohms

`is.ns`

Indicator of north/south track

`track`

Track number

### Details

Resistivity is related to soil salinity.

### Source

William Cleveland, (1993), Visualizing Data. Electronic version from StatLib: https://lib.stat.cmu.edu/datasets/

Cleaned version from Luke Tierney https://homepage.stat.uiowa.edu/~luke/classes/248/examples/soil

### Examples

```
library(agridat)

data(cleveland.soil)
dat <- cleveland.soil

# Similar to Cleveland fig 4.64
## libs(latticeExtra)
## redblue <- colorRampPalette(c("firebrick", "lightgray", "#375997"))
## levelplot(resistivity ~ easting + northing, data = dat,
##           col.regions=redblue,
##           panel=panel.levelplot.points,
##           aspect=2.4, xlab= "Easting (km)", ylab= "Northing (km)",
##           main="cleveland")

# 2D loess plot. Cleveland fig 4.68
sg1 <- expand.grid(easting = seq(.15, 1.410, by = .02),
northing = seq(.150, 3.645, by = .02))
lo1 <- loess(resistivity~easting*northing, data=dat, span = 0.1, degree = 2)
fit1 <- predict(lo1, sg1)
libs(lattice)
redblue <- colorRampPalette(c("firebrick", "lightgray", "#375997"))
levelplot(fit1 ~ sg1\$easting * sg1\$northing,
col.regions=redblue,
cuts = 9,
aspect=2.4, xlab = "Easting (km)", ylab = "Northing (km)",
main="cleveland.soil - 2D smooth of Resistivity")

# ----------------------------------------------------------------------------

## Not run:
# 3D loess plot with data overlaid
libs(rgl)
bg3d(color = "white")
clear3d()
points3d(dat\$easting, dat\$northing, dat\$resistivity / 100,
col = rep("gray50", nrow(dat)))
rgl::surface3d(seq(.15, 1.410, by = .02),
seq(.150, 3.645, by = .02),
fit1/100, alpha=0.9, col=rep("wheat", length(fit1)),
front="fill", back="fill")
rgl.close()

## End(Not run)
```

[Package agridat version 1.18 Index]