files answer01

Import the tidyverse

library(tidyverse)

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## ✔ readr   1.4.0     ✔ forcats 0.5.1

## ── Conflicts ────────────────────────────────────────── tidyverse_conflicts() ──
## ✖ dplyr::filter() masks stats::filter()
## ✖ dplyr::lag()    masks stats::lag()

Read in the file. As whitespace is the delimiter, we need to use read_table. Note that read_delim with delim=" " is the wrong choice as it will try to split on single whitespace characters. read_table is the right choice for multiple whitespace separators.

Note that we should read the DATE as an integer, as it is a year.

temperature <- read_table(
    "https://chryswoods.com/data_analysis_r/cetml1659on.txt",
    skip=6,
    na=c("-99.99", "-99.9"),
    col_types=cols("DATE"=col_integer())
)
temperature

How many years had a negative average temperature in January?

negative_jan <- temperature %>% filter(temperature["JAN"] < 0)
negative_jan

num_negative_jan <- as.numeric(count(negative_jan))
num_negative_jan

## [1] 20

What was the average temperature in June over the years in the data set?

jun_average <- mean(temperature[["JUN"]])
jun_average

## [1] 14.33757

(note that we have to get the column data, and not a 1-column tibble, hence why we use [[ ]])