如何从data.frame制作googleVis多个Sankey？

Question

目标

我的目标是使用googleVis包在R中制作多个Sankey。输出应该类似于：

数据

我在R：

中创建了一些虚拟数据

set.seed(1)

source <- sample(c("North","South","East","West"),100,replace=T)
mid <- sample(c("North ","South ","East ","West "),100,replace=T)
destination <- sample(c("North","South","East","West"),100,replace=T) # N.B. It is important to have a space after the second set of destinations to avoid a cycle
dummy <- rep(1,100) # For aggregation

dat <- data.frame(source,mid,destination,dummy)
aggdat <- aggregate(dummy~source+mid+destination,dat,sum)

到目前为止我尝试了什么

如果我只有一个源和目的地，我可以建立一个有2个变量的Sankey，但不是中间点：

aggdat <- aggregate(dummy~source+destination,dat,sum)

library(googleVis)

p <- gvisSankey(aggdat,from="source",to="destination",weight="dummy")
plot(p)

代码产生了这个：

问题

如何修改

p <- gvisSankey(aggdat,from="source",to="destination",weight="dummy")

也接受mid变量？

Answer 1

函数gvisSankey确实直接接受中级。这些级别必须在底层数据中编码。

 source <- sample(c("NorthSrc", "SouthSrc", "EastSrc", "WestSrc"), 100, replace=T)
 mid <- sample(c("NorthMid", "SouthMid", "EastMid", "WestMid"), 100, replace=T)
 destination <- sample(c("NorthDes", "SouthDes", "EastDes", "WestDes"), 100, replace=T) 
 dummy <- rep(1,100) # For aggregation

现在，我们将重塑原始数据：

 library(dplyr)

 datSM <- dat %>%
  group_by(source, mid) %>%
  summarise(toMid = sum(dummy) ) %>%
  ungroup()

数据框datSM总结了从Source到Mid的单位数。

  datMD <- dat %>%
   group_by(mid, destination) %>%
   summarise(toDes = sum(dummy) ) %>%
   ungroup()

数据框datMD汇总了从中间到目的地的单位数。该数据帧将被添加到最终数据帧中。数据框必须为ungroup并且具有相同的colnames。

  colnames(datSM) <- colnames(datMD) <- c("From", "To", "Dummy")

由于datMD被追加为最后一个，gvisSankey会自动识别中间步骤。

  datVis <- rbind(datSM, datMD)

  p <- gvisSankey(datVis, from="From", to="To", weight="dummy")
  plot(p)

这是情节：