Week 3 Lab Practice

Q1. Count the length of list_data

list_data <- list(c("Red", "Green", "Black"), list("Python", "PHP", "Java"))
print('List:')

## [1] "List:"

print(list_data)

## [[1]]
## [1] "Red"   "Green" "Black"
## 
## [[2]]
## [[2]][[1]]
## [1] "Python"
## 
## [[2]][[2]]
## [1] "PHP"
## 
## [[2]][[3]]
## [1] "Java"

print('Number of objects in the said list:'); print(length(list_data))

## [1] "Number of objects in the said list:"

## [1] 2

Q2. Assign NULL to 2nd and 3rd element

l <- list(1,2,3,4,5)
print('Original list:'); print(l)

## [1] "Original list:"

## [[1]]
## [1] 1
## 
## [[2]]
## [1] 2
## 
## [[3]]
## [1] 3
## 
## [[4]]
## [1] 4
## 
## [[5]]
## [1] 5

print('Set 2nd and 3rd elements to NULL')

## [1] "Set 2nd and 3rd elements to NULL"

l[c(2, 3)] <- list(NULL)
print(l)

## [[1]]
## [1] 1
## 
## [[2]]
## NULL
## 
## [[3]]
## NULL
## 
## [[4]]
## [1] 4
## 
## [[5]]
## [1] 5

print(l)

## [[1]]
## [1] 1
## 
## [[2]]
## NULL
## 
## [[3]]
## NULL
## 
## [[4]]
## [1] 4
## 
## [[5]]
## [1] 5

Q3. Add 10 to each element of the first vector in list1

list1<-list(g1=1:10, g2='R Programming', g3='HTML')
print('Original list:'); print(list1)

## [1] "Original list:"

## $g1
##  [1]  1  2  3  4  5  6  7  8  9 10
## 
## $g2
## [1] "R Programming"
## 
## $g3
## [1] "HTML"

print('New list:')

## [1] "New list:"

list1[[1]]<-list1[[1]]+10
print(list1)

## $g1
##  [1] 11 12 13 14 15 16 17 18 19 20
## 
## $g2
## [1] "R Programming"
## 
## $g3
## [1] "HTML"

Q4. Extract all elements of a first vector except the third element from list2

list2<-list(g1=1:10, g2='R Programming', g3='HTML')
print('Original list:'); print(list2)

## [1] "Original list:"

## $g1
##  [1]  1  2  3  4  5  6  7  8  9 10
## 
## $g2
## [1] "R Programming"
## 
## $g3
## [1] "HTML"

print('First vector:')

## [1] "First vector:"

list2<-list2[[1]][-3]
print((list2))

## [1]  1  2  4  5  6  7  8  9 10

Q5. Add a new item ‘g4=Python’ to list3

list3<-list(g1=1:10, g2='R Programming', g3='HTML')
print('Original list:'); print(list3)

## [1] "Original list:"

## $g1
##  [1]  1  2  3  4  5  6  7  8  9 10
## 
## $g2
## [1] "R Programming"
## 
## $g3
## [1] "HTML"

print('Add a new vector to the said list:')

## [1] "Add a new vector to the said list:"

list3$g4 <- 'Python'
print(list3)

## $g1
##  [1]  1  2  3  4  5  6  7  8  9 10
## 
## $g2
## [1] "R Programming"
## 
## $g3
## [1] "HTML"
## 
## $g4
## [1] "Python"

Q6. Get the length of the first two vectors of list4

list4<-list(g1=1:10, g2='R Programming', g3='HTML')
print('Original list:'); print(list4)

## [1] "Original list:"

## $g1
##  [1]  1  2  3  4  5  6  7  8  9 10
## 
## $g2
## [1] "R Programming"
## 
## $g3
## [1] "HTML"

print('Length of the  vector g1 and g2 of the said list')

## [1] "Length of the  vector g1 and g2 of the said list"

print(length(list4[[1]]))

## [1] 10

print(length(list4[[2]]))

## [1] 1

Q7. Find all elements of l2 that are not in l1

l1<-list('x','y','z')
l2<-list('X','Y','Z','x','y','z')
print('Original list:'); print(l1); print(l2)

## [1] "Original list:"

## [[1]]
## [1] "x"
## 
## [[2]]
## [1] "y"
## 
## [[3]]
## [1] "z"

## [[1]]
## [1] "X"
## 
## [[2]]
## [1] "Y"
## 
## [[3]]
## [1] "Z"
## 
## [[4]]
## [1] "x"
## 
## [[5]]
## [1] "y"
## 
## [[6]]
## [1] "z"

print('All elements of l2 that are not in l1:')

## [1] "All elements of l2 that are not in l1:"

print(setdiff(l2,l1))

## [[1]]
## [1] "X"
## 
## [[2]]
## [1] "Y"
## 
## [[3]]
## [1] "Z"