r - 在networkD3桑基图中的节点标签中放置换行符

Question

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更新:我认为我的问题的答案是你不能插入换行符。一位同事向我指出节点标签是 SVG block ，不支持换行符。

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如何在使用 networkD3 R 包生成的 sankey 图的节点标签中添加换行符？

借用Place text values to right of sankey diagram的例子我可以向标签添加值:

library(networkD3)
library(data.table)
set.seed(1999)
links <- data.table(
  src = rep(0:4, times=c(1,1,2,3,5)),
  target = sample(1:11, 12, TRUE),
  value = sample(100, 12)
)[src < target, ]  # no loops
nodes <- data.table(name=LETTERS[1:12])

#### Need to hover to get counts
##sankeyNetwork(Links=links, Nodes=nodes, Source='src', Target='target',
##  Value='value', NodeID='name', fontSize=16)

## Add text to label
txt <- links[, .(total = sum(value)), by=c('target')]
nodes[txt$target+1L, name := paste0(name, ' (', txt$total, ')')]

## Displays the counts as part of the labels
sankeyNetwork(Links=links, Nodes=nodes, Source='src', Target='target',
  Value='value', NodeID='name', fontSize=16, width=600, height=300)

我希望我可以天真地调整 paste0 以包含换行符，例如:

 name := paste0(name, "\n ", txt$total)

或

name := paste0(name, "<br/> ", txt$total)

但是我还没有能够让任何东西工作，而且我的 JavaScript 太生锈了，无法在它生成后尝试修复它。

Answer 1

您可以将 SVG 文本元素替换为 <foreignObject>文本/html block 。这个例子需要大量额外的格式/定位才能有用，但它表明这是可能的......

library(networkD3)
library(htmlwidgets)
library(data.table)

set.seed(1999)
links <- data.table(
  src = rep(0:4, times=c(1,1,2,3,5)),
  target = sample(1:11, 12, TRUE),
  value = sample(100, 12)
)[src < target, ]  # no loops
nodes <- data.table(name=LETTERS[1:12])

## Add text to label
txt <- links[, .(total = sum(value)), by=c('target')]
nodes[txt$target+1L, name := paste0(name, '<br>(', txt$total, ')')]

## Displays the counts as part of the labels
sn <- sankeyNetwork(Links=links, Nodes=nodes, Source='src', Target='target',
              Value='value', NodeID='name', fontSize=16, width=600, height=300)

onRender(sn,
         '
  function(el,x) {
    d3.selectAll(".node text").remove()
    d3.selectAll(".node")
      .append("foreignObject")
      .attr("width", 100)
      .attr("height", 50)
      .html(function(d) { return d.name; })
  }
  '
)