Mini Project 1

Question 1

data(cars)
median(cars$speed)

## [1] 15

Question 2

df <- read.csv("Mini Project-2/On_Time_Performance.csv")

dim(df)

## [1] 570131    110

Question 3

df <- read.csv("Mini Project-2/On_Time_Performance.csv", stringsAsFactors = FALSE)
missing_count <- sum(is.na(df$Div2WheelsOff))
missing_count

## [1] 570122

Question 4

library(dplyr)

## 
## Attaching package: 'dplyr'

## The following objects are masked from 'package:stats':
## 
##     filter, lag

## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union

df <- read.csv("Mini Project-2/On_Time_Performance.csv", stringsAsFactors = FALSE)
avg_dep_delay <- df %>%
  group_by(UniqueCarrier) %>%
  summarize(avg_dep_delay = mean(DepDelay, na.rm = TRUE)) %>%
  arrange(desc(avg_dep_delay))
print(avg_dep_delay)

## # A tibble: 18 × 2
##    UniqueCarrier avg_dep_delay
##    <chr>                 <dbl>
##  1 B6                    20.4 
##  2 F9                    16.0 
##  3 OO                    15.1 
##  4 OH                    13.8 
##  5 EV                    13.6 
##  6 9E                    12.4 
##  7 G4                    10.4 
##  8 DL                     9.74
##  9 YV                     8.86
## 10 MQ                     8.82
## 11 WN                     8.03
## 12 YX                     7.26
## 13 AA                     6.93
## 14 UA                     5.87
## 15 NK                     5.61
## 16 VX                     2.83
## 17 HA                     1.72
## 18 AS                    -2.25

carrier_with_max_delay <- avg_dep_delay$UniqueCarrier[1]
print(carrier_with_max_delay)

## [1] "B6"

Question 5

library(jsonlite)
url <- "https://min-api.cryptocompare.com/data/v2/histoday?fsym=BTC&tsym=USD&limit=99"
btc_json <- fromJSON(url)
btc_data <- btc_json$Data$Data
max_close_price <- max(btc_data$close, na.rm = TRUE)
print(max_close_price)

## [1] 106155.6