Every pairwise contrast between a cohort's groups

Enumerates every pairwise combination of the groups in x, so a caller can turn each pair into a comparison (for example, filtering a cohort down to one side and diffing an analysis table against the other).

Usage

cohort_contrasts(x, by = NULL)

Arguments

x

Either a Cohort (then by is required, and cohort_groups() runs internally) or the tibble cohort_groups() already returned (then by must not be given).

by

Character vector of subject_tbl columns to group by. Only used when x is a Cohort.

Value

A tibble with one row per pair: group_a, group_b (the two groups' labels), subject_ids_a, subject_ids_b (list-columns of subject ids), and n_a, n_b (their sizes).

Details

This is deliberately minimal: it does not repeat the raw by values on each row. Join back to cohort_groups()'s output on group_label for those.

See also

cohort_groups(), cohort_filter()

Examples

data(example_cohort)
contrasts <- cohort_contrasts(example_cohort, by = "species")
contrasts
#> # A tibble: 1 × 6
#>   group_a group_b subject_ids_a subject_ids_b   n_a   n_b
#>   <chr>   <chr>   <list>        <list>        <int> <int>
#> 1 mouse   rat     <chr [2]>     <chr [2]>         2     2

cohort_filter(example_cohort, subject_ids = contrasts$subject_ids_a[[1]])
#> 
#> ── Cohort: Cross-species genomics comparison 
#> • 2 subjects (2 mouse)
#> • 6 samples (4 wes, 2 scrna)
#> ℹ Extra sample columns: fastq_1, fastq_2