##########
##
# Reading the data into R:

ff <- tempfile()
cat(file=ff, "
1 1 A 31
2 1 B 39.5
3 1 C 30.5
1 2 B 34
2 2 C 24.5
3 2 A 28
1 3 C 15
2 3 A 25.5
3 3 B 31
", sep=" ")

options(scipen=999) # suppressing scientific notation

wheatLS <- read.table(ff, header=FALSE, col.names=c("location", "orientation", "variety", "yield")) 
  
# Note we could also save the data columns into a file and use a command such as:
# wheatLS <- read.table(file = "z:/stat_516/filename.txt", header=FALSE, col.names = c("location", "orientation", "variety", "yield"))

attach(wheatLS)

# Making "location", "orientation" and "variety" factors:

location <- factor(location)

orientation <- factor(orientation)

variety <- factor(variety)

# The data frame called wheatLS is now created.
#########