abc.R

seq(1,20,by = 2)

##  [1]  1  3  5  7  9 11 13 15 17 19

rep(5,4)

## [1] 5 5 5 5

m <- matrix(1:9, nrow = 3, ncol = 3)

df= data.frame(
  name = c("A","B","C"),
  age = c(20,22,21)
)

df

##   name age
## 1    A  20
## 2    B  22
## 3    C  21

df$age

## [1] 20 22 21

df$name

## [1] "A" "B" "C"

df$age

## [1] 20 22 21

df[1,2]

## [1] 20

X = as.character(5.2)
X

## [1] "5.2"

c(1,2,3) + 2 

## [1] 3 4 5

x = -100:100
y = x^2
z = -10:10
plot(x,y,type = 'l', main = 'Line Plot')