Assignment 3

#QUESTION 1

library(RCurl)
x <- getURL("https://raw.githubusercontent.com/fivethirtyeight/data/master/college-majors/majors-list.csv")
y <- data.frame(read.csv(text=x))
summary(y)

##     FOD1P              Major           Major_Category    
##  Length:174         Length:174         Length:174        
##  Class :character   Class :character   Class :character  
##  Mode  :character   Mode  :character   Mode  :character

library(stringr)
y$Major[str_detect(y$Major,pattern="\\DATA|\\STATISTICS")]

## [1] "MANAGEMENT INFORMATION SYSTEMS AND STATISTICS"
## [2] "COMPUTER PROGRAMMING AND DATA PROCESSING"     
## [3] "STATISTICS AND DECISION SCIENCE"

#QUESTION 2

df <- data.frame(c("bell pepper","bilberry","blackberry","blood orange","blueberry","cantaloupe","chili pepper","cloudberry","elderberry","lime"    ,     "lychee"  ,     "mulberry","olive"    ,    "salal berry"))

x <- cat(paste(df,collapse=","))

## c("bell pepper", "bilberry", "blackberry", "blood orange", "blueberry", "cantaloupe", "chili pepper", "cloudberry", "elderberry", "lime", "lychee", "mulberry", "olive", "salal berry")

#QUESTION 3

1. Same character appearing consecutively thrice.

example <- c("aaa","banana")
str_view(example,"(.)\\1\\1")

2.

Repeated pair of the same letters (aa), in between the same letter(s)-like a palindrome

example <- c("saas","banana")
str_view(example,"(.)(.)\\2\\1")

3. Repeated pair of letters (i.e. an in banana)

example <- c("saas","banana")
str_view(example,"(..)\\1")

4. Same letter appearing alternatively, thrice (example a in (b)‘anana’)

example <- c("hahaha","banana")
str_view(example,"(.).\\1.\\1")

5. Same letter appearing consecutively thrice, followed by a different letter, then the same initial letters appearing thrice again.

example <-c("rrrprrrttcuwjsoooo")
str_view(example,"(.)(.)(.).*\\3\\2\\1")

#QUESTION 4

1. Starts and ends with the same character:

example <- c("roar","eye","gig","grab")
str_view(example,"(.).*\\1")

2.Contain a repeated pair of letters (e.g. “church” contains “ch” repeated twice.)

example <- c("church","banana","grab")
str_view(example,"(..).*\\1")

3.Contain one letter repeated in at least three places (e.g. “eleven” contains three “e”s.)

example <- c("eleven","grab")
str_view(example,"(.).*\\1.*\\1")