Prepares data from Pimentel page 156.

data-raw/peanutYield.R

+##----------------------------------------------------------------------
+## Data generation.
+
+peanutYield <- expand.grid(
+    variety=c("40-Roxo", "54-Roxo", "49-Cateto", "53-Tatu"),
+    loc=c("Campinas", "Ribeirão Preto", "Pindorama"),
+    year=c("1941-42", "1942-43", "1949-50"),
+    KEEP.OUT.ATTRS=FALSE)
+
+peanutYield$meanYield <-
+    c(1780, 1450, 1430, 790, 690, 470, 520, 280, 4400, 4330, 3440, 3710,
+      2610, 2590, 2710, 1590, 1570, 1330, 1500, 1170, 1850, 2010, 2240,
+      1790, 2570, 2320, 2130, 2220, 2650, 2740, 1890, 1570, 2100, 2160,
+      1570, 870)
+
+addmargins(with(peanutYield,
+                tapply(meanYield, list(variety, loc), FUN=sum)))
+
+peanutYield <- peanutYield[with(peanutYield,
+                                order(year, loc, variety)),]
+
+str(peanutYield)
+
+## save(peanutYield, file="../data/peanutYield.RData")
+
+##----------------------------------------------------------------------
+## Examples.
+
+require(lattice)
+
+xyplot(meanYield~variety|year, data=peanutYield,
+       groups=loc, type="o",
+       ylab=expression(Yield~(t~ha^{-1})),
+       xlab="Variety")
+
+rm(list=ls())
+load("../data/peanutYield.RData")
+ls()
+str(peanutYield)