# single line comment

'

multiline comment

'

# types

10.5 55 # numeric

1L 55L # integer

4i 9+3i # complex

'foo' # character (string)

TRUE FALSE # logical (boolean)

class(TRUE) # check type

# operator

+ - * / # arithmetic

^ # exponent

%% # remainder

%/% # integer division

<- -> <<- ->> # assignment

== != > < >= <= # comparison

! && || & | # logical

: # sequence generator

%in% # does elem belong to vector

%*% # matrix multiplication

# structs

c(1,2,3,4) # vector

c('a','b','c') # ...

list('a','b','c') # list

matrix(c(1,2,3,4),2,2) # matrix

array(1:10) # array

array(c('a','b')) # ...

array(1:10,c(5,5)) # ... 2d

# some arr ops

array(c('green','yellow'),c(2,4))

foo <- list(1,2,3)

foo <- append(foo,4)

foo <- list(1,2,3)

foo <- foo[-1]

seq(1,4)

seq(-4,4,length=100)

# var

a <- 'foo'

a <- 2

a <- 3

3 -> a

g <<- 3 # global assignment

3 ->> g

# cond

if () {}

if () {} else if () {}

if () {} else if () {} else {}

# loop

for (i in 1:20) {

if (i %% 2 == 0) { next }

if (i == 17) { break }

print(i)

}

i <- 0

while (i < 20) {

i <- i + 1

print(i)

if (i %% 2 == 0) { next }

if (i == 17) { break }

}

# fn

myfn <- function(a, b=25, name='john') {

num <- a * b

res <- paste(c(name, 'is', num, 'years old'), collapse=' ')

return(res)

}