代码展示
加载R包
library(tidyverse) library(igraph) library(showtext) library(thematic) # install.packages("thematic")
构建数据
dat <- tribble( ~from, ~to, 'Are you a horse?', 'No', 'Are you a horse?', 'Yes', 'Are you a horse?', 'Maybe', 'Maybe', 'How many legs\ndo you walk on?', 'Yes', 'How many legs\ndo you walk on?', 'No', 'You\'re not a horse', 'How many legs\ndo you walk on?', 'Two', 'How many legs\ndo you walk on?', 'Four', 'Two', 'You\'re not a horse_2', 'Four', 'Really?', 'Really?', 'No_2', 'Really?', 'Yes_2', 'No_2', 'Can you read\nand write?', 'Yes_2', 'Can you read\nand write?', 'Can you read\nand write?', 'Yes_3', 'Can you read\nand write?', 'No_3', 'Yes_3', 'You\'re not a horse_3', 'No_3', 'You\'re reading this,\naren\'t you?', 'You\'re reading this,\naren\'t you?', 'Yes_4', 'Yes_4', 'You\'re not a horse_4' )
创建图形和布局
graph <- graph_from_data_frame(dat, directed = TRUE) coords <- graph %>% layout_as_tree() %>% as_tibble(.name_repair = ~c('x', 'y')) output <- coords %>% mutate(step = vertex_attr(graph, 'name'),label = str_remove(step, '\\_.+'), x = -2.5 * x,y = 5 * y,type = case_when(str_detect(label, '\\?') ~ "Question", str_detect(step, 'You\'re not a horse') ~ 'Outcome',T ~ 'Answer'))
制作盒子
box_width <- 1.2 box_height <- 1.25 boxes <- output %>%mutate(xmin = x - box_width,xmax = x + box_width,ymin = case_when( str_detect(step, '(legs|reading|write)') ~ y - 1.5 * box_height,T ~ y - box_height), ymax = case_when(str_detect(step, '(legs|reading|write)') ~ y + 1.5 * box_height,T ~ y + box_height))
制作边文件
edges <- dat %>% mutate(id = row_number()) %>% pivot_longer(cols = c("from", "to"),names_to = "s_e",values_to = "step") %>%left_join(boxes, by = "step") %>% select(-c(label, type, y, xmin, xmax)) %>% mutate(y = ifelse(s_e == "from", ymin, ymax)) %>% select(-c(ymin, ymax)) %>% mutate(x = case_when(s_e == 'to' & id %in% c(5, 14) ~ x - box_width,T ~ x)) base_colors <- thematic::okabe_ito(2)
数据可视化
ggplot() +geom_path(data = edges, aes(x,y, group = id),arrow = arrow(length = unit(0.25, 'cm'))) + geom_rect(data = boxes,aes(xmin=xmin,xmax = xmax, ymin = ymin, ymax = ymax, fill = type)) + geom_text(data = boxes,aes(x = x, y = y,label = label),lineheight = 1) + theme_void() + theme(legend.position = 'none', plot.background = element_rect(fill = 'white', colour = NA)) + scale_fill_manual(values = c('Question' = base_colors[1], 'Answer' = colorspace::lighten(base_colors[1], 0.5), 'Outcome' = colorspace::lighten(base_colors[2], 0.1))) + coord_cartesian(xlim = c(-4.5,5))
