Question 1: The vector name stores the extracted names.
library(tidyverse)
## -- Attaching packages ---------------------------------------------------------------- tidyverse 1.2.1 --
## v ggplot2 2.2.1 v purrr 0.2.4
## v tibble 1.4.1 v dplyr 0.7.4
## v tidyr 0.7.2 v stringr 1.2.0
## v readr 1.1.1 v forcats 0.2.0
## -- Conflicts ------------------------------------------------------------------- tidyverse_conflicts() --
## x dplyr::filter() masks stats::filter()
## x dplyr::lag() masks stats::lag()
library(stringi)
raw.data <-"555-1239Moe Szyslak(636) 555-0113Burns, C. Montgomery555-6542Rev. Timothy Lovejoy555 8904Ned Flanders636-555-3226Simpson, Homer5553642Dr. Julius Hibbert"
raw.data
## [1] "555-1239Moe Szyslak(636) 555-0113Burns, C. Montgomery555-6542Rev. Timothy Lovejoy555 8904Ned Flanders636-555-3226Simpson, Homer5553642Dr. Julius Hibbert"
unlist(str_extract_all(raw.data, "[[:alpha:]., ]{2,}"))
## [1] "Moe Szyslak" "Burns, C. Montgomery" "Rev. Timothy Lovejoy"
## [4] "Ned Flanders" "Simpson, Homer" "Dr. Julius Hibbert"
#extract words
original_names <- unlist(str_extract_all(raw.data, "[[:alpha:]., ]{2,}"))
#remove middle names -
names01 <- str_replace(original_names, "\\s[A-z]\\. ", " ")
#restructure first name last name
names02 <- str_replace(names01, "(\\w+),\\s(\\w+)", "\\2 \\1")
#remove title:
new_names <- str_replace(names02, "[A-z]{2,3}\\. ", " ")
new_names
## [1] "Moe Szyslak" "Montgomery Burns" " Timothy Lovejoy"
## [4] "Ned Flanders" "Homer Simpson" " Julius Hibbert"
original_names_df<- data.frame(original_names)
original_names_df
## original_names
## 1 Moe Szyslak
## 2 Burns, C. Montgomery
## 3 Rev. Timothy Lovejoy
## 4 Ned Flanders
## 5 Simpson, Homer
## 6 Dr. Julius Hibbert
new_names_df <- data.frame(new_names)
new_names_df
## new_names
## 1 Moe Szyslak
## 2 Montgomery Burns
## 3 Timothy Lovejoy
## 4 Ned Flanders
## 5 Homer Simpson
## 6 Julius Hibbert
title <- str_detect(names02,"[A-z]{2,3}\\. ")
title_df <- data.frame(names02, title)
title_df
## names02 title
## 1 Moe Szyslak FALSE
## 2 Montgomery Burns FALSE
## 3 Rev. Timothy Lovejoy TRUE
## 4 Ned Flanders FALSE
## 5 Homer Simpson FALSE
## 6 Dr. Julius Hibbert TRUE
second_name <- str_detect(original_names, "[A-Z]{1}\\.")
sec_name_df <- data.frame(original_names, second_name)
sec_name_df
## original_names second_name
## 1 Moe Szyslak FALSE
## 2 Burns, C. Montgomery TRUE
## 3 Rev. Timothy Lovejoy FALSE
## 4 Ned Flanders FALSE
## 5 Simpson, Homer FALSE
## 6 Dr. Julius Hibbert FALSE
Question 2: Describe the types of strings that conform to the following regular expressions and construct an example that is matched by the regular expression.
reg_a <- "534435457$saf!@#3123$"
str_extract_all(reg_a, "[0-9]+\\$" )
## [[1]]
## [1] "534435457$" "3123$"
winter_olympics <- 'Winter Olympics started last week'
str_extract_all(winter_olympics, "\\b[a-z]{1,4}\\b")
## [[1]]
## [1] "last" "week"
data_text <- c("Data607.txt", "Data.txt!", "data-science.pdf")
str_extract_all(data_text, ".*?\\.txt$")
## [[1]]
## [1] "Data607.txt"
##
## [[2]]
## character(0)
##
## [[3]]
## character(0)
date_test <- c("01/01/18", "02/18/2018", "Feb 14, 2018")
str_extract_all(date_test, "\\d{2}/\\d{2}/\\d{4}")
## [[1]]
## character(0)
##
## [[2]]
## [1] "02/18/2018"
##
## [[3]]
## character(0)
tag_test <- c('<tag>this is a tag</tag>', '<data>data tag</data>', '<not a tag>','<DATA607> Data Acquistion with R</DATA607>')
str_extract_all(tag_test, "<(.+?)>.+?</\\1>")
## [[1]]
## [1] "<tag>this is a tag</tag>"
##
## [[2]]
## [1] "<data>data tag</data>"
##
## [[3]]
## character(0)
##
## [[4]]
## [1] "<DATA607> Data Acquistion with R</DATA607>"
Question 3: The following code hides a secret message. Crack it with R and regular expressions. Hint: Some of the characters are more revealing than others! The code snippet is also available in the materials at www.r-datacollection.com.
data.hidden <- 'clcopCow1zmstc0d87wnkig7OvdicpNuggvhryn92Gjuwczi8hqrfpRxs5Aj5dwpn0Tanwo Uwisdij7Lj8kpf03AT5Idr3coc0bt7yczjatOaootj55t3Nj3ne6c4Sfek.r1w1YwwojigO d6vrfUrbz2.2bkAnbhzgv4R9i05zEcrop.wAgnb.SqoU65fPa1otfb7wEm24k6t3sR9zqe5 fy89n6Nd5t9kc4fE905gmc4Rgxo5nhDk! gr'
secret_message <- unlist(str_extract_all(data.hidden, "[[:upper:].]+"))
secret_message
## [1] "C" "O" "N" "G" "R" "A" "T" "U" "L" "AT" "I" "O" "N" "S"
## [15] "." "Y" "O" "U" "." "A" "R" "E" "." "A" ".S" "U" "P" "E"
## [29] "R" "N" "E" "R" "D"
decoded.message <- str_replace_all(paste0(secret_message, collapse = ''), "[.]", " ")
decoded.message
## [1] "CONGRATULATIONS YOU ARE A SUPERNERD"