找出每个因子之间的不同值，并在r中绘制直方图

Question

我正在学习r，我想基于每个因素的转数来建立直方图，具体取决于数据框中的日期。

这是我的数据框：

dat <- data.frame(
  time = factor(c("Breakfast","Breakfast","Breakfast","Breakfast","Lunch","Lunch","Lunch","Lunch","Dinner","Dinner","Dinner","Dinner"), levels=c("Breakfast","Lunch","Dinner")), 
  date=c("2020-01-20","2020-01-21","2020-01-22","2020-01-23","2020-01-20","2020-01-21","2020-01-22","2020-01-23","2020-01-20","2020-01-21","2020-01-22","2020-01-23"),
  total_bill = c(12.75,13.5,25.5,27.4,18.3,19.9,27.8,28.6,15.7,17.4,19.5,24.2)
)

[我的目标是找到例如：Breakfast因子，我想像13.5 - 12.75，25.5 - 13.5，27.4 - 25.5一样获得它的公转数，并且我想对Lunch，Dinner进行同样的处理，然后使用通过使用ggplot在3个不同的图中绘制这些差值。

对此将提供任何帮助。谢谢！！！

我正在学习r，我想基于每个因素的转数来建立直方图，具体取决于数据框中的日期。这是我的数据帧：dat

Answer 1

我们通过指定cut通过breaks创建一个组>

library(dplyr)
dat %>% 
   mutate(grp = cut(total_bill, breaks = c(-Inf, 12.75, 13.5, 25.5, 27.4, Inf)))