Please deliver links to an R Markdown file (in GitHub and rpubs.com) with solutions to the problems below. You may work in a small group, but please submit separately with names of all group participants in your submission.
# import file, set header = FALSE to get row name header
majors <- read.csv('https://raw.githubusercontent.com/fivethirtyeight/data/master/college-majors/majors-list.csv', header = TRUE, sep = ",")
head (majors) #get a glimpse of the data## FOD1P Major Major_Category
## 1 1100 GENERAL AGRICULTURE Agriculture & Natural Resources
## 2 1101 AGRICULTURE PRODUCTION AND MANAGEMENT Agriculture & Natural Resources
## 3 1102 AGRICULTURAL ECONOMICS Agriculture & Natural Resources
## 4 1103 ANIMAL SCIENCES Agriculture & Natural Resources
## 5 1104 FOOD SCIENCE Agriculture & Natural Resources
## 6 1105 PLANT SCIENCE AND AGRONOMY Agriculture & Natural Resourcessubset(majors, regexpr("DATA|STATISTICS",majors$Major)>0)## FOD1P Major Major_Category
## 44 6212 MANAGEMENT INFORMATION SYSTEMS AND STATISTICS Business
## 52 2101 COMPUTER PROGRAMMING AND DATA PROCESSING Computers & Mathematics
## 59 3702 STATISTICS AND DECISION SCIENCE Computers & Mathematics##2 Write code that transforms the data below: [1] “bell pepper”
“bilberry” “blackberry” “blood orange” [5] “blueberry” “cantaloupe”
“chili pepper” “cloudberry”
[9] “elderberry” “lime” “lychee” “mulberry”
[13] “olive” “salal berry”
Into a format like this: c(“bell pepper”, “bilberry”, “blackberry”, “blood orange”, “blueberry”, “cantaloupe”, “chili pepper”, “cloudberry”, “elderberry”, “lime”, “lychee”, “mulberry”, “olive”, “salal berry”)
mystring <- str_c('c([1] "bell pepper" "bilberry" "blackberry" "blood orange"
[5] "blueberry" "cantaloupe" "chili pepper" "cloudberry"
[9] "elderberry" "lime" "lychee" "mulberry"
[13] "olive" "salal berry"')
mystring## [1] "c([1] \"bell pepper\" \"bilberry\" \"blackberry\" \"blood orange\"\n[5] \"blueberry\" \"cantaloupe\" \"chili pepper\" \"cloudberry\" \n[9] \"elderberry\" \"lime\" \"lychee\" \"mulberry\" \n[13] \"olive\" \"salal berry\""str_view(mystring, "\\[")#can't figure out how to proceed from here...##3 Describe, in words, what these expressions will match:
(.)\1\1 - the ‘(.)’ means select any character, and ‘\1’ means repeat character before it once each time it appears, so this means that a particular character will be repeated three times in a row.
“(.)(.)\2\1” - select any two characters, repeat them is reverse order (\2 tells us this), once (\1). So ‘em’ becomes ‘emme’
(..)\1 - repeats any two characters
“(.).\1.\1” - a character then any character then 1st character any character again, then 1st character “(.)(.)(.).*\3\2\1” - three characters then any character or number repeated three times in reverse order
##4 Construct regular expressions to match words that:
#Start and end with the same character.
str_subset(words, "^(.)((.*\\1$)|\\1?$)")## [1] "a" "america" "area" "dad" "dead"
## [6] "depend" "educate" "else" "encourage" "engine"
## [11] "europe" "evidence" "example" "excuse" "exercise"
## [16] "expense" "experience" "eye" "health" "high"
## [21] "knock" "level" "local" "nation" "non"
## [26] "rather" "refer" "remember" "serious" "stairs"
## [31] "test" "tonight" "transport" "treat" "trust"
## [36] "window" "yesterday"#Contain a repeated pair of letters (e.g. "church" contains "ch" repeated twice.)
str_subset(words, "([A-Za-z][A-Za-z]).*\\1")## [1] "appropriate" "church" "condition" "decide" "environment"
## [6] "london" "paragraph" "particular" "photograph" "prepare"
## [11] "pressure" "remember" "represent" "require" "sense"
## [16] "therefore" "understand" "whether"#Contain one letter repeated in at least three places (e.g. "eleven" contains three "e"s.)
str_subset(words, "([a-z]).*\\1.*\\1")## [1] "appropriate" "available" "believe" "between" "business"
## [6] "degree" "difference" "discuss" "eleven" "environment"
## [11] "evidence" "exercise" "expense" "experience" "individual"
## [16] "paragraph" "receive" "remember" "represent" "telephone"
## [21] "therefore" "tomorrow"