Split data frame by groups

group_split() works like base::split() but:

• It uses the grouping structure from group_by() and therefore is subject to the data mask

• It does not name the elements of the list based on the grouping as this only works well for a single character grouping variable. Instead, use group_keys() to access a data frame that defines the groups.

group_split() is primarily designed to work with grouped data frames. You can pass ... to group and split an ungrouped data frame, but this is generally not very useful as you want have easy access to the group metadata.

# S3 method for class 'SummarizedExperiment'
group_split(.tbl, ..., .keep = TRUE)

Arguments

.tbl

A tbl.

...

If .tbl is an ungrouped data frame, a grouping specification, forwarded to group_by().

.keep

Should the grouping columns be kept?

Value

A list of tibbles. Each tibble contains the rows of .tbl for the associated group and all the columns, including the grouping variables. Note that this returns a list_of which is slightly stricter than a simple list but is useful for representing lists where every element has the same type.

Lifecycle

group_split() is not stable because you can achieve very similar results by manipulating the nested column returned from tidyr::nest(.by =). That also retains the group keys all within a single data structure. group_split() may be deprecated in the future.

References

Hutchison, W.J., Keyes, T.J., The tidyomics Consortium. et al. The tidyomics ecosystem: enhancing omic data analyses. Nat Methods 21, 1166–1170 (2024). https://doi.org/10.1038/s41592-024-02299-2

Wickham, H., François, R., Henry, L., Müller, K., Vaughan, D. (2023). dplyr: A Grammar of Data Manipulation. R package version 2.1.4, https://CRAN.R-project.org/package=dplyr

See also

Other grouping functions: group_by(), group_map(), group_nest(), group_trim()

Examples

data(pasilla, package = "tidySummarizedExperiment")
pasilla |> group_split(condition)
#> [[1]]
#> class: SummarizedExperiment 
#> dim: 14599 4 
#> metadata(2): latest_mutate_scope_report latest_select_scope_report
#> assays(1): counts
#> rownames(14599): FBgn0000003 FBgn0000008 ... FBgn0261574 FBgn0261575
#> rowData names(0):
#> colnames(4): untrt1 untrt2 untrt3 untrt4
#> colData names(2): type condition
#> 
#> [[2]]
#> class: SummarizedExperiment 
#> dim: 14599 3 
#> metadata(2): latest_mutate_scope_report latest_select_scope_report
#> assays(1): counts
#> rownames(14599): FBgn0000003 FBgn0000008 ... FBgn0261574 FBgn0261575
#> rowData names(0):
#> colnames(3): trt1 trt2 trt3
#> colData names(2): type condition
#> 
pasilla |> group_split(counts > 0)
#> [[1]]
#> class: SummarizedExperiment 
#> dim: 5536 7 
#> metadata(2): latest_mutate_scope_report latest_select_scope_report
#> assays(1): counts
#> rownames(5536): FBgn0000003 FBgn0000015 ... FBgn0261508 FBgn0261514
#> rowData names(0):
#> colnames(7): untrt1 untrt2 ... trt2 trt3
#> colData names(3): condition type counts > 0
#> 
#> [[2]]
#> class: SummarizedExperiment 
#> dim: 12359 7 
#> metadata(2): latest_mutate_scope_report latest_select_scope_report
#> assays(1): counts
#> rownames(12359): FBgn0000008 FBgn0000014 ... FBgn0261401 FBgn0261568
#> rowData names(0):
#> colnames(7): untrt1 untrt2 ... trt2 trt3
#> colData names(3): condition type counts > 0
#> 
pasilla |> group_split(condition, counts > 0)
#> [[1]]
#> class: SummarizedExperiment 
#> dim: 5271 4 
#> metadata(2): latest_mutate_scope_report latest_select_scope_report
#> assays(1): counts
#> rownames(5271): FBgn0000003 FBgn0000015 ... FBgn0260968 FBgn0261356
#> rowData names(0):
#> colnames(4): untrt1 untrt2 untrt3 untrt4
#> colData names(3): type condition counts > 0
#> 
#> [[2]]
#> class: SummarizedExperiment 
#> dim: 11886 4 
#> metadata(2): latest_mutate_scope_report latest_select_scope_report
#> assays(1): counts
#> rownames(11886): FBgn0000008 FBgn0000014 ... FBgn0261361 FBgn0261523
#> rowData names(0):
#> colnames(4): untrt1 untrt2 untrt3 untrt4
#> colData names(3): type condition counts > 0
#> 
#> [[3]]
#> class: SummarizedExperiment 
#> dim: 4990 3 
#> metadata(2): latest_mutate_scope_report latest_select_scope_report
#> assays(1): counts
#> rownames(4990): FBgn0000003 FBgn0000022 ... FBgn0261508 FBgn0261514
#> rowData names(0):
#> colnames(3): trt1 trt2 trt3
#> colData names(3): type condition counts > 0
#> 
#> [[4]]
#> class: SummarizedExperiment 
#> dim: 11730 3 
#> metadata(2): latest_mutate_scope_report latest_select_scope_report
#> assays(1): counts
#> rownames(11730): FBgn0000008 FBgn0000014 ... FBgn0261401 FBgn0261568
#> rowData names(0):
#> colnames(3): trt1 trt2 trt3
#> colData names(3): type condition counts > 0
#>