diff --git a/iteration.Rmd b/iteration.Rmd index 322b491..c689a60 100644 --- a/iteration.Rmd +++ b/iteration.Rmd @@ -102,7 +102,7 @@ Then we'll move on some variations of the for loop that help you solve other pro 1. Compute the mean of every column in `mtcars`. 2. Determine the type of each column in `nycflights13::flights`. - 3. Compute the number of unique values in each column of `iris`. + 3. Compute the number of unique values in each column of `palmerpenguins::penguins`. 4. Generate 10 random normals from distributions with means of -10, 0, 10, and 100. Think about the output, sequence, and body **before** you start writing the loop. @@ -346,14 +346,14 @@ However, it is good to know they exist so that you're prepared for problems wher What if the names are not unique? 3. Write a function that prints the mean of each numeric column in a data frame, along with its name. - For example, `show_mean(iris)` would print: + For example, `show_mean(mpg)` would print: ```{r, eval = FALSE} - show_mean(iris) - #> Sepal.Length: 5.84 - #> Sepal.Width: 3.06 - #> Petal.Length: 3.76 - #> Petal.Width: 1.20 + show_mean(mpg) + #> displ: 3.47 + #> year: 2004 + #> cyl: 5.89 + #> cty: 16.86 ``` (Extra challenge: what function did I use to make sure that the numbers lined up nicely, even though the variable names had different lengths?) @@ -636,7 +636,7 @@ I focus on purrr functions here because they have more consistent names and argu 1. Compute the mean of every column in `mtcars`. 2. Determine the type of each column in `nycflights13::flights`. - 3. Compute the number of unique values in each column of `iris`. + 3. Compute the number of unique values in each column of `palmerpenguins::penguins`. 4. Generate 10 random normals from distributions with means of -10, 0, 10, and 100. 2. How can you create a single vector that for each column in a data frame indicates whether or not it's a factor? @@ -909,11 +909,11 @@ A number of functions work with **predicate** functions that return either a sin `keep()` and `discard()` keep elements of the input where the predicate is `TRUE` or `FALSE` respectively: ```{r} -iris %>% +gss_cat %>% keep(is.factor) %>% str() -iris %>% +gss_cat %>% discard(is.factor) %>% str() ``` diff --git a/tibble.Rmd b/tibble.Rmd index 5c90546..ce41ede 100644 --- a/tibble.Rmd +++ b/tibble.Rmd @@ -26,7 +26,7 @@ Most other R packages use regular data frames, so you might want to coerce a dat You can do that with `as_tibble()`: ```{r} -as_tibble(iris) +as_tibble(mtcars) ``` You can create a new tibble from individual vectors with `tibble()`.