7+3
15-19
4*67
56/9
2^6
27%/%3.4
27%%3.4
7*3.4+3.2
16^(1/2)
2^(1/3)

x <- c(1,4,7)
y <- c(2,4,6,4,6,10)
A <- matrix(c(2,3,4,5,6,7,1,2,3), nrow=3)
A
B <- rbind(c(0,0,1), c(2,4,5), c(1,4,2))
B
A*B
x+y
A/y

abs(-10.56)
floor(5.6)
ceiling(5.6)
log(x)
log(x, base=2)
cos(A)
atan(A)
exp(y)

A%*%B   #matrix multiplication
z <- c(2,3,1)
z%*%x   #vector dot product
t(A)    # transpose of a matrix
diag(A)   # extract the diagonal
sum(diag(A))   # trace of a matrix
X <- diag(c(1,2,3,4)) # create a diagonal matrix
X
I <-  diag(4) # create an identity matrix
I
solve(B)
eigen(A)    # compute eigenvalues and eigenvectors of a matrix
prod(eigen(A)$values)   # determinant

A <- rbind( c(2,3), c(1,-2))
A
solve(A, c(13,-4))
solve(A)  # getting the inverse
solve(rbind(c(1,2), c(2,4))) # getting the inverse of a singular matrix

x
pnorm(x)
pnorm(x, mean=2, sd=2)
dnorm(x)
qchisq(c(0.90,0.95,0.99), 2)
runif(30, -10, 10)

x <- seq(1,10, length=8)
y <- seq(1,10,length=9)^2
stepfun(x,y)
plot.stepfun(stepfun(x,y))