R visUpdateEdges：创建新边而不是更新现有边

Question

我有一个动态网络，我想用 R shiny 和 visNetwork 来表示它。根据选择的节点，节点和边的颜色应该根据一些外部协议/数据（下面代码中的节点列表和边列表）而改变。

这对节点非常有效：我选择了一个节点，并且在未来的所有时间步骤中，节点的颜色会根据数据而变化。为此，我使用visUpdateNodes。

但是当我尝试使用visUpdateEdges 对边缘进行基本相同的操作时，它无法正常工作：不仅为节点着色，还创建了新节点（使用正确的颜色）。

这里有一个简单的例子：

library(shiny)
library(tidyverse)
library(visNetwork)

# some data - these values are for the updating process
nodeslist <- list(id1 = data_frame(R1 = c("red", "orange", "orange"), R2 = c("red", 
  "black", "green"), R3 = c("red", "cyan", "yellow")), id2 = data_frame(R1 = c("orange", 
  "red", "orange"), R2 = c("black", "red", "green"), R3 = c("orange", "red", 
  "yellow")), id3 = data_frame(R1 = c("orange", "orange", "red"), R2 = c("black", 
  "yellow", "red"), R3 = c("brown", "cyan", "red")))

edgeslist <- list(id1 = data_frame(R1 = c("red", "orange", "orange"), R2 = c("red", 
  "black", "green"), R3 = rep("black", 3)), id2 = data_frame(R1 = c("orange", 
  "red", "orange"), R2 = c("black", "red", "green"), R3 = rep("black", 3)), 
  id3 = data_frame(R1 = c("orange", "orange", "red"), R2 = c("black", "yellow", 
    "red"), R3 = rep("black", 3)))

# the updating functions
changeColorOfOtherNodes <- function(nodes, selected.node, index) {
  nodes %>% mutate(color = unlist(nodeslist[[as.numeric(selected.node)]][, 
    index]))
}

changeColorOfEdges <- function(edges, selected.node, index) {
  edges %>% mutate(color = unlist(edgeslist[[as.numeric(selected.node)]][, 
    index]))
}


# making the network
id <- c(1, 2, 3)
color <- rep("cyan", length(id))
nodes <- data_frame(id, color)

from <- c(1, 2, 3)
to <- c(2, 3, 1)
edges <- data_frame(from, to, color = rep("#333333", 3), value = c(2, 2, 2))



# shiny application
server <- shinyServer(function(input, output, session) {

  output$netplot <- renderVisNetwork({
    visNetwork(nodes, edges) %>% visOptions(nodesIdSelection = list(enabled = TRUE))
  })

  observe({
    if (!is.null(input$netplot_selected) && input$netplot_selected > 0) {

      for (i in 1:ncol(nodeslist[[as.numeric(input$netplot_selected)]])) {

        # updating works well for nodes
        nodes <- changeColorOfOtherNodes(nodes, input$netplot_selected, 
          index = i)
        visNetworkProxy("netplot") %>% visUpdateNodes(nodes)
        Sys.sleep(1)
        # updating for edges -> new edges are creates, but don't know why
        edges <- changeColorOfEdges(edges, input$netplot_selected, index = i)
        visNetworkProxy("netplot") %>% visUpdateEdges(edges)
        Sys.sleep(1)
        print(edges)
      }

    }
  })

})


ui <- shinyUI(fluidPage(mainPanel(visNetworkOutput("netplot"))))
shinyApp(server = server, ui = ui)

有人知道如何使用 visUpdateEdges 正确更新节点的颜色吗？为什么visUpdateEdges 会创建新边而不是更新现有边？

Answer 1

您必须在边 data.frame 中设置 id 并使用它来引用 visUpdateEdges 中的现有边

edge <- data.frame(id = 1:3, from = ....)
# update color of edge 1
visUpdateEdges(data.frame(id = 1, color = "red"))