3.8 Practice (OPTIONAL)

Practice the following operations. Type the directly into the console and execute them. Also write them in a script in the script editor and run them.

Square roots

sqrt(42)

## [1] 6.480741

The date Some functions in R can be executed within nothing in the parentheses.

date()

## [1] "Thu Sep 13 00:19:52 2018"

Exponents The ^ is used for exponents

42^2

## [1] 1764

A series of numbers A colon between two numbers creates a series of numbers.

1:42

##  [1]  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 21 22 23
## [24] 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42

logs The default for the log() function is the natural log.

log(42)

## [1] 3.73767

log10() gives the base-10 log.

log10(42)

## [1] 1.623249

exp() raises e to a power

exp(3.73767)

## [1] 42.00002

Multiple commands can be nested

sqrt(42)^2
log(sqrt(42)^2)
exp(log(sqrt(42)^2))