## -----------------------------------------------------------------------------
a <- 1:5
b <- 6:10


## -----------------------------------------------------------------------------
d <- a * b
a
b
d


## -----------------------------------------------------------------------------
a * 3


## -----------------------------------------------------------------------------
a + c(1,10)


## -----------------------------------------------------------------------------
1:6 + c(0,10)


## -----------------------------------------------------------------------------
a <- 1:5
b <- 6:10
a == 2


## -----------------------------------------------------------------------------
a < 3
b >= 9


## -----------------------------------------------------------------------------
a
b
b > 6 & b < 8

# combining a and b
b > 9 | a <= 2


## -----------------------------------------------------------------------------
sqrt(a)
exp(a)


## -----------------------------------------------------------------------------
min(a)
max(a)
range(a)
sum(a)
mean(a)
median(a)
prod(a)
sd(a)


## -----------------------------------------------------------------------------
r <- runif(10)
r


## -----------------------------------------------------------------------------
r <- rnorm(10, mean=10, sd=2)
r


## -----------------------------------------------------------------------------
set.seed(12)
runif(2)
runif(3)
runif(4)

set.seed(12)
runif(1)
runif(2)

set.seed(12)
runif(3)
runif(5)


## -----------------------------------------------------------------------------
set.seed(999)
runif(3)
runif(5)


## -----------------------------------------------------------------------------
# set up an example matrix
m <- matrix(1:6, ncol=3, nrow=2, byrow=TRUE)
m

m * 2

m^2


## -----------------------------------------------------------------------------
m * 1:2


## -----------------------------------------------------------------------------
m * m


## -----------------------------------------------------------------------------
m %*% t(m)