将文本添加到R中的DiagrammeR流程图流程图中

Question

以下代码使用DiagrammeR包在R中创建流程图。如何添加＆＃34;是＆＃34;或＆＃34;否＆＃34; （或任何其他文字）连接形状的流线？创建图表时，我的节点通常会做出决定，我想将流程答案标记为是/否。

library(DiagrammeR)

grViz("
digraph boxes_and_circles {

      # a 'graph' statement
      graph [overlap = true, fontsize = 10]

      # several 'node' statements
      node [shape = box,
      fontname = Helvetica]
      A; B; C; D; E; F

      node [shape = circle,
      fixedsize = true,
      width = 0.9] // sets as circles
      1; 2; 3; 4; 5; 6; 7; 8

      # several 'edge' statements
      A->1 B->2 B->3 B->4 C->A
      1->D E->A 2->4 1->5 1->F
      E->6 4->6 5->7 6->7 3->8
      }
      ")