chac_data <- "i'm 'very' hungry."
stringr::str_length("i am hungry.")## [1] 12stringr::str_c(c("I", "am"), collapse = "")## [1] "Iam"stringr::str_c("I", "am", sep = ";")## [1] "I;am"str_sort(c("John", "Mary", "Aaron"))## [1] "Aaron" "John" "Mary"flights %>% glimpse()## Rows: 336,776
## Columns: 19
## $ year <int> 2013, 2013, 2013, 2013, 2013, 2013, 2013, 2013, 2013, 2…
## $ month <int> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1…
## $ day <int> 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1…
## $ dep_time <int> 517, 533, 542, 544, 554, 554, 555, 557, 557, 558, 558, …
## $ sched_dep_time <int> 515, 529, 540, 545, 600, 558, 600, 600, 600, 600, 600, …
## $ dep_delay <dbl> 2, 4, 2, -1, -6, -4, -5, -3, -3, -2, -2, -2, -2, -2, -1…
## $ arr_time <int> 830, 850, 923, 1004, 812, 740, 913, 709, 838, 753, 849,…
## $ sched_arr_time <int> 819, 830, 850, 1022, 837, 728, 854, 723, 846, 745, 851,…
## $ arr_delay <dbl> 11, 20, 33, -18, -25, 12, 19, -14, -8, 8, -2, -3, 7, -1…
## $ carrier <chr> "UA", "UA", "AA", "B6", "DL", "UA", "B6", "EV", "B6", "…
## $ flight <int> 1545, 1714, 1141, 725, 461, 1696, 507, 5708, 79, 301, 4…
## $ tailnum <chr> "N14228", "N24211", "N619AA", "N804JB", "N668DN", "N394…
## $ origin <chr> "EWR", "LGA", "JFK", "JFK", "LGA", "EWR", "EWR", "LGA",…
## $ dest <chr> "IAH", "IAH", "MIA", "BQN", "ATL", "ORD", "FLL", "IAD",…
## $ air_time <dbl> 227, 227, 160, 183, 116, 150, 158, 53, 140, 138, 149, 1…
## $ distance <dbl> 1400, 1416, 1089, 1576, 762, 719, 1065, 229, 944, 733, …
## $ hour <dbl> 5, 5, 5, 5, 6, 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 5, 6, 6, 6…
## $ minute <dbl> 15, 29, 40, 45, 0, 58, 0, 0, 0, 0, 0, 0, 0, 0, 0, 59, 0…
## $ time_hour <dttm> 2013-01-01 05:00:00, 2013-01-01 05:00:00, 2013-01-01 0…flights_small <- flights %>% select(where(is.character)) %>% head(n = 10)flights_small %>% filter(str_detect(origin, "M"))## # A tibble: 0 × 4
## # ℹ 4 variables: carrier <chr>, tailnum <chr>, origin <chr>, dest <chr>flights_small %>% filter(str_detect(origin, ".M"))## # A tibble: 0 × 4
## # ℹ 4 variables: carrier <chr>, tailnum <chr>, origin <chr>, dest <chr>flights_small %>% filter(str_detect(origin, "M."))## # A tibble: 0 × 4
## # ℹ 4 variables: carrier <chr>, tailnum <chr>, origin <chr>, dest <chr>flights_small %>% filter(str_detect(origin, "M\\."))## # A tibble: 0 × 4
## # ℹ 4 variables: carrier <chr>, tailnum <chr>, origin <chr>, dest <chr>flights_small %>% filter(str_detect(origin, "E$"))## # A tibble: 0 × 4
## # ℹ 4 variables: carrier <chr>, tailnum <chr>, origin <chr>, dest <chr>flights_small %>% filter(str_detect(carrier, "\\d"))## # A tibble: 3 × 4
## carrier tailnum origin dest
## <chr> <chr> <chr> <chr>
## 1 B6 N804JB JFK BQN
## 2 B6 N516JB EWR FLL
## 3 B6 N593JB JFK MCOflights_small %>% filter(str_detect(carrier, "\\s"))## # A tibble: 0 × 4
## # ℹ 4 variables: carrier <chr>, tailnum <chr>, origin <chr>, dest <chr>flights_small %>% filter(str_detect(carrier, "[ABD]"))## # A tibble: 9 × 4
## carrier tailnum origin dest
## <chr> <chr> <chr> <chr>
## 1 UA N14228 EWR IAH
## 2 UA N24211 LGA IAH
## 3 AA N619AA JFK MIA
## 4 B6 N804JB JFK BQN
## 5 DL N668DN LGA ATL
## 6 UA N39463 EWR ORD
## 7 B6 N516JB EWR FLL
## 8 B6 N593JB JFK MCO
## 9 AA N3ALAA LGA ORDflights_small %>% filter(str_detect(carrier, "[^ABD]"))## # A tibble: 8 × 4
## carrier tailnum origin dest
## <chr> <chr> <chr> <chr>
## 1 UA N14228 EWR IAH
## 2 UA N24211 LGA IAH
## 3 B6 N804JB JFK BQN
## 4 DL N668DN LGA ATL
## 5 UA N39463 EWR ORD
## 6 B6 N516JB EWR FLL
## 7 EV N829AS LGA IAD
## 8 B6 N593JB JFK MCO# ? 0 or 1
flights %>% filter(str_detect(carrier, "A"))## # A tibble: 92,450 × 19
## year month day dep_time sched_dep_time dep_delay arr_time sched_arr_time
## <int> <int> <int> <int> <int> <dbl> <int> <int>
## 1 2013 1 1 517 515 2 830 819
## 2 2013 1 1 533 529 4 850 830
## 3 2013 1 1 542 540 2 923 850
## 4 2013 1 1 554 558 -4 740 728
## 5 2013 1 1 558 600 -2 753 745
## 6 2013 1 1 558 600 -2 924 917
## 7 2013 1 1 558 600 -2 923 937
## 8 2013 1 1 559 600 -1 941 910
## 9 2013 1 1 559 600 -1 854 902
## 10 2013 1 1 606 610 -4 858 910
## # ℹ 92,440 more rows
## # ℹ 11 more variables: arr_delay <dbl>, carrier <chr>, flight <int>,
## # tailnum <chr>, origin <chr>, dest <chr>, air_time <dbl>, distance <dbl>,
## # hour <dbl>, minute <dbl>, time_hour <dttm># + 1 or more
flights_small %>% filter(str_detect(carrier, "A?"))## # A tibble: 10 × 4
## carrier tailnum origin dest
## <chr> <chr> <chr> <chr>
## 1 UA N14228 EWR IAH
## 2 UA N24211 LGA IAH
## 3 AA N619AA JFK MIA
## 4 B6 N804JB JFK BQN
## 5 DL N668DN LGA ATL
## 6 UA N39463 EWR ORD
## 7 B6 N516JB EWR FLL
## 8 EV N829AS LGA IAD
## 9 B6 N593JB JFK MCO
## 10 AA N3ALAA LGA ORD# * 0 or more
flights_small %>% filter(str_detect(carrier, "A*"))## # A tibble: 10 × 4
## carrier tailnum origin dest
## <chr> <chr> <chr> <chr>
## 1 UA N14228 EWR IAH
## 2 UA N24211 LGA IAH
## 3 AA N619AA JFK MIA
## 4 B6 N804JB JFK BQN
## 5 DL N668DN LGA ATL
## 6 UA N39463 EWR ORD
## 7 B6 N516JB EWR FLL
## 8 EV N829AS LGA IAD
## 9 B6 N593JB JFK MCO
## 10 AA N3ALAA LGA ORD# (..)\\1
flights_small %>% select(where(is.character)) %>% filter(str_detect(tailnum, "(\\d{2})\\1"))## # A tibble: 0 × 4
## # ℹ 4 variables: carrier <chr>, tailnum <chr>, origin <chr>, dest <chr>flights_small %>%
summarise(sum(str_detect(tailnum, "8$")))## # A tibble: 1 × 1
## `sum(str_detect(tailnum, "8$"))`
## <int>
## 1 1str_detect(flights_small$tailnum, "8$")## [1] TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSEsum(str_detect(flights_small$tailnum, "8$"))## [1] 1mean(str_detect(flights_small$tailnum, "8$"))## [1] 0.1colours <- c("red", "orange", "yellow", "green", "blue", "purple")
colour_match <- str_c(colours, collapse = "|")
colour_match## [1] "red|orange|yellow|green|blue|purple"#extract strings with a color
has_colour <- str_subset(sentences, colour_match)
str_subset(sentences, colour_match)## [1] "Glue the sheet to the dark blue background."
## [2] "Two blue fish swam in the tank."
## [3] "The colt reared and threw the tall rider."
## [4] "The wide road shimmered in the hot sun."
## [5] "See the cat glaring at the scared mouse."
## [6] "A wisp of cloud hung in the blue air."
## [7] "Leaves turn brown and yellow in the fall."
## [8] "He ordered peach pie with ice cream."
## [9] "Pure bred poodles have curls."
## [10] "The spot on the blotter was made by green ink."
## [11] "Mud was spattered on the front of his white shirt."
## [12] "The sofa cushion is red and of light weight."
## [13] "The sky that morning was clear and bright blue."
## [14] "Torn scraps littered the stone floor."
## [15] "The doctor cured him with these pills."
## [16] "The new girl was fired today at noon."
## [17] "The third act was dull and tired the players."
## [18] "A blue crane is a tall wading bird."
## [19] "Live wires should be kept covered."
## [20] "It is hard to erase blue or red ink."
## [21] "The wreck occurred by the bank on Main Street."
## [22] "The lamp shone with a steady green flame."
## [23] "The box is held by a bright red snapper."
## [24] "The prince ordered his head chopped off."
## [25] "The houses are built of red clay bricks."
## [26] "The red tape bound the smuggled food."
## [27] "Nine men were hired to dig the ruins."
## [28] "The flint sputtered and lit a pine torch."
## [29] "Hedge apples may stain your hands green."
## [30] "The old pan was covered with hard fudge."
## [31] "The plant grew large and green in the window."
## [32] "The store walls were lined with colored frocks."
## [33] "The purple tie was ten years old."
## [34] "Bathe and relax in the cool green grass."
## [35] "The clan gathered on each dull night."
## [36] "The lake sparkled in the red hot sun."
## [37] "Mark the spot with a sign painted red."
## [38] "Smoke poured out of every crack."
## [39] "Serve the hot rum to the tired heroes."
## [40] "The couch cover and hall drapes were blue."
## [41] "He offered proof in the form of a large chart."
## [42] "A man in a blue sweater sat at the desk."
## [43] "A sip of tea revives his tired friend."
## [44] "The door was barred, locked, and bolted as well."
## [45] "A thick coat of black paint covered all."
## [46] "The small red neon lamp went out."
## [47] "Paint the sockets in the wall dull green."
## [48] "Wake and rise, and step into the green outdoors."
## [49] "The green light in the brown box flickered."
## [50] "He put his last cartridge into the gun and fired."
## [51] "The ram scared the school children off."
## [52] "Tear a thin sheet from the yellow pad."
## [53] "Dimes showered down from all sides."
## [54] "The sky in the west is tinged with orange red."
## [55] "The red paper brightened the dim stage."
## [56] "The hail pattered on the burnt brown grass."
## [57] "The big red apple fell to the ground."# Extract strings with a noun
noun <- "(a|the) ([^ ]+)"
had_nouns <- str_subset(sentences, noun) %>% head(10)
had_nouns %>% str_extract(noun)## [1] "the smooth" "the sheet" "the depth" "a chicken" "the parked"
## [6] "the sun" "the huge" "the ball" "the woman" "a helps"flights_small %>% mutate(tailnum_rev = tailnum %>% str_replace("^[A-Z]", "-"))## # A tibble: 10 × 5
## carrier tailnum origin dest tailnum_rev
## <chr> <chr> <chr> <chr> <chr>
## 1 UA N14228 EWR IAH -14228
## 2 UA N24211 LGA IAH -24211
## 3 AA N619AA JFK MIA -619AA
## 4 B6 N804JB JFK BQN -804JB
## 5 DL N668DN LGA ATL -668DN
## 6 UA N39463 EWR ORD -39463
## 7 B6 N516JB EWR FLL -516JB
## 8 EV N829AS LGA IAD -829AS
## 9 B6 N593JB JFK MCO -593JB
## 10 AA N3ALAA LGA ORD -3ALAAflights_small %>% mutate(tailnum_rev = tailnum %>% str_replace_all("[A-Z]", "-"))## # A tibble: 10 × 5
## carrier tailnum origin dest tailnum_rev
## <chr> <chr> <chr> <chr> <chr>
## 1 UA N14228 EWR IAH -14228
## 2 UA N24211 LGA IAH -24211
## 3 AA N619AA JFK MIA -619--
## 4 B6 N804JB JFK BQN -804--
## 5 DL N668DN LGA ATL -668--
## 6 UA N39463 EWR ORD -39463
## 7 B6 N516JB EWR FLL -516--
## 8 EV N829AS LGA IAD -829--
## 9 B6 N593JB JFK MCO -593--
## 10 AA N3ALAA LGA ORD -3----sentences[1] %>% str_split(" ", n = 3, simplify = TRUE)## [,1] [,2] [,3]
## [1,] "The" "birch" "canoe slid on the smooth planks."flights_small %>% filter(str_detect(origin, regex("^e", ignore_case = TRUE)))## # A tibble: 3 × 4
## carrier tailnum origin dest
## <chr> <chr> <chr> <chr>
## 1 UA N14228 EWR IAH
## 2 UA N39463 EWR ORD
## 3 B6 N516JB EWR FLL