R Bioinformatics Cookbook

How it works...

Using nested dataframes can be done with the following steps:

1. Create a nested dataframe:

library(tidyr)library(dplyr)library(purrr)library(magrittr)library(ggplot2)nested_mt <- nest(mtcars, -cyl)

2. Add a new list column holding the results of lm():

nested_mt_list_cols <- nested_mt %>% mutate( model = map(data, ~ lm(mpg ~ wt, data = .x)))

3. Add a new list column holding the results of tidy():

nested_mt_list_cols <- nested_mt_list_cols %>% mutate( tidy_model = map(model, tidy))

4. Unnest the whole dataframe:

unnest(nested_mt_list_cols, tidy_model)

5. Run the pipeline in a single step:

models_df <- nest(mtcars, -cyl) %>% mutate( model = map(data, ~ lm(mpg ~ wt, data = .x)), tidy_model = map(model, tidy) ) %>% unnest(tidy_model) ...