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Provide arguments to nest() and unnest() to get rid of warnings (#825)

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Maria Paula Caldas
2020-10-03 16:43:41 +02:00
committed by GitHub
parent 50adc6a9f3
commit 9eb33d8dcc
1 changed files with 6 additions and 6 deletions
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12
model-many.Rmd
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@@ -351,7 +351,7 @@ You can also use it on an ungrouped data frame, specifying which columns you wan
```{r} ```{r}
gapminder %>% gapminder %>%
nest(year:gdpPercap) nest(data = c(year:gdpPercap))
``` ```
### From vectorised functions ### From vectorised functions
@@ -374,7 +374,7 @@ df %>%
```{r} ```{r}
df %>% df %>%
mutate(x2 = stringr::str_split(x1, ",")) %>% mutate(x2 = stringr::str_split(x1, ",")) %>%
unnest() unnest(x2)
``` ```
(If you find yourself using this pattern a lot, make sure to check out `tidyr::separate_rows()` which is a wrapper around this common pattern). (If you find yourself using this pattern a lot, make sure to check out `tidyr::separate_rows()` which is a wrapper around this common pattern).
@@ -420,7 +420,7 @@ probs <- c(0.01, 0.25, 0.5, 0.75, 0.99)
mtcars %>% mtcars %>%
group_by(cyl) %>% group_by(cyl) %>%
summarise(p = list(probs), q = list(quantile(mpg, probs))) %>% summarise(p = list(probs), q = list(quantile(mpg, probs))) %>%
unnest() unnest(c(p, q))
``` ```
### From a named list ### From a named list
@@ -464,7 +464,7 @@ df %>%
mtcars %>% mtcars %>%
group_by(cyl) %>% group_by(cyl) %>%
summarise(q = list(quantile(mpg))) %>% summarise(q = list(quantile(mpg))) %>%
unnest() unnest(q)
``` ```
1. What does this code do? Why might might it be useful? 1. What does this code do? Why might might it be useful?
@@ -540,7 +540,7 @@ df1 <- tribble(
2, "c", 3 2, "c", 3
) )
df1 df1
df1 %>% unnest(y, z) df1 %>% unnest(c(y, z))
# Doesn't work because y and z have different number of elements # Doesn't work because y and z have different number of elements
df2 <- tribble( df2 <- tribble(
@@ -549,7 +549,7 @@ df2 <- tribble(
2, c("b", "c"), 3 2, c("b", "c"), 3
) )
df2 df2
df2 %>% unnest(y, z) df2 %>% unnest(c(y, z))
``` ```
The same principle applies when unnesting list-columns of data frames. You can unnest multiple list-cols as long as all the data frames in each row have the same number of rows. The same principle applies when unnesting list-columns of data frames. You can unnest multiple list-cols as long as all the data frames in each row have the same number of rows.