Assignment 5

1. join + filter - Which airplanes fly LGA to XNA (1 POINT)

q1 <- flights %>%
  filter(origin == "LGA" & dest == "XNA") %>%
  select(tailnum) %>%
  distinct()
head(q1)

## # A tibble: 6 × 1
##   tailnum
##   <chr>  
## 1 N722MQ 
## 2 N719MQ 
## 3 N739MQ 
## 4 N711MQ 
## 5 N723MQ 
## 6 N730MQ

2. join - Add the airline name to the flights table (1 POINT)

q2 <- flights %>%
  left_join(airlines, by = "carrier")
head(q2)

## # A tibble: 6 × 20
##    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      544            545        -1     1004           1022
## 5  2013     1     1      554            600        -6      812            837
## 6  2013     1     1      554            558        -4      740            728
## # ℹ 12 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>, name <chr>

3. join + select + distinct() - Which airports have no commercial flights (1 POINT)

q3 <- flights %>%
  select(origin) %>%
  distinct() %>%
  rename(faa = origin)

airports_no_flights <- airports %>%
  anti_join(q3, by = "faa") %>%
  select(faa, name)
head(q3)

## # A tibble: 3 × 1
##   faa  
##   <chr>
## 1 EWR  
## 2 LGA  
## 3 JFK

4. EXTRA CREDIT - (2 POINT2) - NO HELP - NO PARTIAL CREDIT

Create a table with the names of the airports with the most

winds (wind_speed > 30). The table must contain only the airport

name (airports$name) and no duplicate rows

q4 <- weather %>%
  filter(wind_speed > 30) %>%
  select(origin) %>%
  distinct() %>%
  left_join(airports, by = c("origin" = "faa")) %>%
  select(name) %>%
  distinct()
head(q4)

## # A tibble: 3 × 1
##   name               
##   <chr>              
## 1 Newark Liberty Intl
## 2 John F Kennedy Intl
## 3 La Guardia