digraph PreProcessingForVariantDiscovery_GATK4 {
  #rankdir=LR;
  compound=true;

  # Links
  SCATTER_1_VARIABLE_unmapped_bam -> CALL_MergeBamAlignment
  CALL_SortAndFixTags -> CALL_BaseRecalibrator
  SCATTER_2_VARIABLE_subgroup -> CALL_ApplyBQSR
  CALL_CreateSequenceGroupingTSV -> SCATTER_2_VARIABLE_subgroup
  CALL_GatherBqsrReports -> CALL_ApplyBQSR
  CALL_SortAndFixTags -> CALL_ApplyBQSR
  CALL_CreateSequenceGroupingTSV -> SCATTER_0_VARIABLE_subgroup
  CALL_MergeBamAlignment -> CALL_MarkDuplicates
  SCATTER_1_VARIABLE_unmapped_bam -> CALL_SamToFastqAndBwaMem
  CALL_GetBwaVersion -> CALL_MergeBamAlignment
  CALL_ApplyBQSR -> CALL_GatherBamFiles
  CALL_MarkDuplicates -> CALL_SortAndFixTags
  CALL_BaseRecalibrator -> CALL_GatherBqsrReports
  SCATTER_0_VARIABLE_subgroup -> CALL_BaseRecalibrator
  CALL_SamToFastqAndBwaMem -> CALL_MergeBamAlignment

  # Nodes
  CALL_SortAndFixTags [label="call SortAndFixTags"]
  subgraph cluster_1 {
    style="filled,solid";
    fillcolor=white;
    CALL_SamToFastqAndBwaMem [label="call SamToFastqAndBwaMem"]
    CALL_MergeBamAlignment [label="call MergeBamAlignment"]
    SCATTER_1_VARIABLE_unmapped_bam [shape="hexagon" label="scatter over File as unmapped_bam"]
  }
  CALL_GetBwaVersion [label="call GetBwaVersion"]
  CALL_GatherBamFiles [label="call GatherBamFiles"]
  subgraph cluster_2 {
    style="filled,solid";
    fillcolor=white;
    CALL_ApplyBQSR [label="call ApplyBQSR"]
    SCATTER_2_VARIABLE_subgroup [shape="hexagon" label="scatter over Array[String] as subgroup"]
  }
  CALL_MarkDuplicates [label="call MarkDuplicates"]
  CALL_CreateSequenceGroupingTSV [label="call CreateSequenceGroupingTSV"]
  subgraph cluster_0 {
    style="filled,solid";
    fillcolor=white;
    CALL_BaseRecalibrator [label="call BaseRecalibrator"]
    SCATTER_0_VARIABLE_subgroup [shape="hexagon" label="scatter over Array[String] as subgroup"]
  }
  CALL_GatherBqsrReports [label="call GatherBqsrReports"]
}