вам нужно использовать пустые / пустые узлы, что-то вроде этого (если вы не хотите, чтобы стрелки добавляли [dir = none]
к последним строкам, например (blank_3 -> Fun1 [dir = none]
):
library(DiagrammeR)
grViz("
digraph {
node[shape=box, width = 4, height = 1]
blank_1 [label = '',color = white];
President;
blank_2 [label = '',color = white];
blank_3[label = '', width = 0.01, height = 0.01];
blank_4[label = '', width = 0.01, height = 0.01];
blank_5[label = '', width = 0.01, height = 0.01];
Fun1;
Fun2;
Fun3;
{rank = same; blank_1 President blank_2}
{rank = same; blank_3 blank_4 blank_5}
{rank = same; Fun1 Fun2 Fun3}
blank_1 -> President [dir = none, color = White]
President -> blank_2 [dir = none, color = White]
President -> blank_4 [dir = none]
blank_1 -> blank_3 [dir = none, color = White]
blank_2 -> blank_5 [dir = none, color = White]
blank_3 -> blank_4 [dir = none]
blank_4 -> blank_5 [dir = none]
blank_3 -> Fun1
blank_4 -> Fun2
blank_5 -> Fun3
}
")