Branch Between Alternative Paths — mlr_graphs

Create a multiplexed graph.

All input arguments are cloned and have no references in common with the returned Graph.

Usage

pipeline_branch(graphs, prefix_branchops = "", prefix_paths = FALSE)

Arguments

graphs: list of Graph
Multiple graphs, possibly named. They all must have exactly one output. If any of the arguments are named, then all must have unique names.
prefix_branchops: character(1)
Optional id prefix to prepend to PipeOpBranch and PipeOpUnbranch id. Their resulting IDs will be "[prefix_branchops]branch" and "[prefix_branchops]unbranch". Default is "".
prefix_paths: logical(1) | character(1)
Whether to add prefixes to graph IDs when performing gunion. Can be helpful to avoid ID clashes in resulting graph. Default FALSE. If this is TRUE, the prefixes are taken from the names of the input arguments if present or "poX" where X counts up. If this is a character(1), it is a prefix that is added to the PipeOp IDs additionally to the input argument list.

Value

Graph

Examples

library("mlr3")

po_pca = po("pca")
po_nop = po("nop")

branches = pipeline_branch(list(pca = po_pca, nothing = po_nop))
# gives the same as
branches = c("pca", "nothing")
po("branch", branches) %>>%
  gunion(list(po_pca, po_nop)) %>>%
  po("unbranch", branches)
#> Graph with 4 PipeOps:
#>        ID         State sccssors prdcssors
#>    <char>        <char>   <char>    <char>
#>    branch <<UNTRAINED>>  pca,nop          
#>       pca <<UNTRAINED>> unbranch    branch
#>       nop <<UNTRAINED>> unbranch    branch
#>  unbranch <<UNTRAINED>>            pca,nop

pipeline_branch(list(pca = po_pca, nothing = po_nop),
  prefix_branchops = "br_", prefix_paths = "xy_")
#> Graph with 4 PipeOps:
#>              ID         State               sccssors              prdcssors
#>          <char>        <char>                 <char>                 <char>
#>       br_branch <<UNTRAINED>> xy_pca.pca,xy_nothi...                       
#>      xy_pca.pca <<UNTRAINED>>            br_unbranch              br_branch
#>  xy_nothing.nop <<UNTRAINED>>            br_unbranch              br_branch
#>     br_unbranch <<UNTRAINED>>                        xy_pca.pca,xy_nothi...
# gives the same as
po("branch", branches, id = "br_branch") %>>%
  gunion(list(xy_pca = po_pca, xy_nothing = po_nop)) %>>%
  po("unbranch", branches, id = "br_unbranch")
#> Graph with 4 PipeOps:
#>              ID         State               sccssors              prdcssors
#>          <char>        <char>                 <char>                 <char>
#>       br_branch <<UNTRAINED>> xy_pca.pca,xy_nothi...                       
#>      xy_pca.pca <<UNTRAINED>>            br_unbranch              br_branch
#>  xy_nothing.nop <<UNTRAINED>>            br_unbranch              br_branch
#>     br_unbranch <<UNTRAINED>>                        xy_pca.pca,xy_nothi...