To print a listing of all examples of a chapter, use ch3()
.
To run all the examples of ch3()
, use example(ch3)
.
Examples
if (interactive()) {
# Chapter 3 - The Fundamentals of R
# Using the Full Power of Functions
## Vectorizing your functions
baskets.of.Granny <- c(12,4,4,6,9,3)
baskets.of.Granny
sum(baskets.of.Granny)
firstnames <- c("Joris", "Carolien", "Koen")
lastname <- "Meys"
paste(firstnames,lastname)
authors <- c("Andrie","Joris")
lastnames <- c("de Vries","Meys")
paste(authors,lastnames)
## Putting the argument in a function
# print() ### This line of code leads to deliberate error for illustration
print(x = "Isn't this fun?")
print(digits=4, x = 11/7)
# Making history
filename <- file.path(tempdir(), "Chapter3.Rhistory")
if (FALSE) {
savehistory(file = filename)
}
list.files(tempdir(), pattern = ".Rhistory")
if (FALSE) {
loadhistory(file.path(tempdir(), "Chapter3.Rhistory"))
}
# Keeping Your Code Readable
## Following naming conventions
## Choosing a clear name
paste <- paste("This gets","confusing")
paste
paste("Don't","you","think?")
## Choosing a naming style
## Structuring your code
baskets.of.Geraldine <- c(5,3,2,2,12,9)
Intro <- "It is amazing! The All Star Grannies scored
a total of"
Outro <- "baskets in the last six games!"
Total.baskets <- baskets.of.Granny +
baskets.of.Geraldine
Text <- paste(Intro,
sum(Total.baskets),
Outro)
cat(Text)
Text
cat('If you doubt whether it works,
+ just try it out.')
## Adding comments
# The All Star Grannies do it again!
baskets.of.Granny <- c(12,4,4,6,9,3) # Granny rules
sum(baskets.of.Granny) # total number of points
# Getting from Base R to More
## Finding packages
## Installing packages
if (FALSE) {
install.packages("fortunes")
}
library("fortunes")
fortune("This is R")
fortune(161)
detach(package:fortunes)
}