在 R Shiny 中,如何为一系列链接矩阵输入建立反应链?

In R Shiny, how to establish a reactivity chain for a series of linked matrix inputs?

在下面的“简化”代码中,有一系列 3 个链接的用户输入矩阵。用户可以选择仅修改矩阵 1(在滑块输入周期 X 内给出直线输出,值为 Y)。用户可以选择通过将 X 和 Y 值输入矩阵 2 来向矩阵 1“Y”值添加曲线,随着用户添加输入,矩阵会垂直扩展(添加行)。除了 Matrix 2 中生成的第一条曲线之外,用户还可以选择添加曲线场景,方法是将 X 和 Y 值输入到 Matrix 3 中,该矩阵在水平和垂直方向上都展开。在绘图中,矩阵 3 优先于矩阵 2,矩阵 2 优先于矩阵 1。“曲线”是指 interpolation/extrapolation 函数 (UDF interpol())。 Matrix 1 馈入 Matrix 2,后者又馈入 Matrix 3。这些下游馈送似乎工作正常,除非如下所述从 Matrix 2 转到 Matrix 3。

当 运行 下面时,矩阵 1-only 输入工作正常(如下面第一张图所示)。仅矩阵 3 输入工作正常(如下面第三张图片所示)。但是 Matrix 2 输入不能正常工作:正如您在下面的第二张图片中看到的,Matrix 2 输入不能正确地下游到 Matrix 3。

我做错了什么?

代码:

library(ggplot2)
library(shiny)
library(shinyMatrix)

interpol <- function(a, b) { # [a] = modeled periods, [b] = matrix inputs
  c <- b
  c[,1][c[,1] > a] <- a
  d <- diff(c[,1, drop = FALSE])
  d[d <= 0] <- NA
  d <- c(1,d)
  c <- cbind(c,d)
  c <- na.omit(c)
  c <- c[,-c(3),drop=FALSE]
  e <- rep(NA, a)
  e[c[,1]] <- c[,2]
  e[seq_len(min(c[,1])-1)] <- e[min(c[,1])]
  if(max(c[,1]) < a){e[seq(max(c[,1]) + 1, a, 1)] <- 0}
  e <- approx(seq_along(e)[!is.na(e)], e[!is.na(e)], seq_along(e))$y # Interpolates
  return(e)
}

ui <- fluidPage(
  uiOutput("slider"),
  h5(strong("Matrix 1:")), uiOutput("mat1"),
  h5(strong("Matrix 2:")), uiOutput("mat2"),
  h5(strong("Matrix 3:")), uiOutput("mat3"),
  plotOutput("plot")
  )

server <- function(input, output, session){
  
  output$slider <- renderUI({sliderInput('periods', 'Modeled periods (X):', min=1, max=10, value=10)})
  
  output$mat1 <- renderUI({
    matrixInput("matrix1", 
                value = matrix(c(5), 1, 1, dimnames = list("Base rate (Y)",NULL)),
                rows =  list(extend = FALSE, names = TRUE),
                cols =  list(names = FALSE),
                class = "numeric")    
  })
  
  output$mat2 <- renderUI({
    matrixInput("matrix2",
                value = matrix(c(input$periods, input$matrix1[1,1]), 1, 2, dimnames = list(NULL,c("X","Y"))),
                rows = list(extend = TRUE, names = TRUE, delete = TRUE),
                class = "numeric")
  })
  
  output$mat3 <- renderUI({
    matrixInput("matrix3",
                value = matrix(c(input$matrix2[,1], input$matrix2[,2]), 1, 2, dimnames = list(NULL, rep("Scenario 1", 2))),
                rows = list(extend = TRUE, delta = 1, names = TRUE, delete = TRUE),
                cols = list(extend = TRUE, delta = 2, names = TRUE, delete = TRUE, multiheader = TRUE),
                class = "numeric")
  })
  
  observeEvent(input$matrix2, { 
    if(any(rownames(input$matrix2) == "")){
      tmpMatrix <- input$matrix2
      rownames(tmpMatrix) <- paste("Row", seq_len(nrow(input$matrix2)))
      isolate(updateMatrixInput(session, inputId = "matrix2", value = tmpMatrix))
    }
    input$matrix2
  })
  
  observeEvent(input$matrix3, {
    if(any(colnames(input$matrix3) == "")){
      tmpMatrix <- input$matrix3
      colnames(tmpMatrix) <- paste("Scenario",rep(1:ncol(tmpMatrix),each=2,length.out=ncol(tmpMatrix)))
      isolate(updateMatrixInput(session, inputId = "matrix3", value = tmpMatrix))
    }
    input$matrix3
  })
  
  plotData <- reactive({
    req(input$periods)
    tryCatch(
      lapply(seq_len(ncol(input$matrix3)/2), # column counter to set matrix index as it expands
              function(i){
                tibble(
                  Scenario = colnames(input$matrix3)[i*2-1],
                  X = seq_len(input$periods),
                  Y = interpol(input$periods,input$matrix3[,(i*2-1):(i*2), drop = FALSE])
                )
              }) %>% bind_rows(),
      error = function(e) NULL
    )
  })
  
  output$plot <- renderPlot({
    req(plotData())
    plotData() %>% ggplot() + 
      geom_line(aes(x = X, y = Y, colour = as.factor(Scenario))) +
      theme(legend.title=element_blank())
  })
  
}

shinyApp(ui, server)

替代代码,不使用 renderUI 而是依赖 observeEvent 嵌入 updateMatrixInput:

ui <- fluidPage(
  sliderInput('periods', 'Modeled periods (X):', min=1, max=10, value=10),
  
  h5(strong("Matrix 1 is omitted for MWE")), 
  
  h5(strong("Matrix 2:")), 
  matrixInput("matrix2",
              value = matrix(c(10, 5), 1, 2, dimnames = list(NULL,c("X","Y"))),
              rows = list(extend = TRUE, names = TRUE, delete = TRUE),
              class = "numeric"),
  
  h5(strong("Matrix 3:")), 
  matrixInput("matrix3",
              value = matrix(c(10,5), ncol = 2, dimnames = list(NULL, rep("Scenario 1", 2))),
              rows = list(extend = TRUE, delta = 1, names = TRUE, delete = TRUE),
              cols = list(extend = TRUE, delta = 2, names = TRUE, delete = TRUE, multiheader = TRUE),
              class = "numeric"),
  
  plotOutput("plot")
)

server <- function(input, output, session){
  
  observeEvent(input$periods, {
    updateMatrixInput(session, inputId = "matrix2", 
      value = matrix(c(input$periods, 5), 1, 2, dimnames = list(NULL,c("X","Y"))))
  })
  
  observeEvent(input$matrix2, { 
    if(any(rownames(input$matrix2) == "")){
      tmpMatrix <- input$matrix2
      rownames(tmpMatrix) <- paste("Row", seq_len(nrow(input$matrix2)))
      isolate(updateMatrixInput(session, inputId = "matrix2", value = tmpMatrix))
      isolate(updateMatrixInput(session, inputId = "matrix3", 
        value = tmpMatrix))
      }
    input$matrix2
    isolate(
      updateMatrixInput(
        session, 
        inputId = "matrix3", 
        value = matrix(
          c(input$matrix2[,1],input$matrix2[,2]), 
          ncol = 2, 
          dimnames = list(NULL, rep("Scenario 1", 2)))
      )
    )
  })
  
  observeEvent(input$matrix3, {
    if(any(colnames(input$matrix3) == "")){
      tmpMatrix <- input$matrix3
      colnames(tmpMatrix) <- paste("Scenario",rep(1:ncol(tmpMatrix),each=2,length.out=ncol(tmpMatrix)))
      isolate(updateMatrixInput(session, inputId = "matrix3", value = tmpMatrix))
    }
    input$matrix3
  })
  
  plotData <- reactive({
    req(input$periods)
    tryCatch(
      lapply(seq_len(ncol(input$matrix3)/2), # column counter to set matrix index as it expands
             function(i){
               tibble(
                 Scenario = colnames(input$matrix3)[i*2-1],
                 X = seq_len(input$periods),
                 Y = interpol(input$periods,input$matrix3[,(i*2-1):(i*2), drop = FALSE])
               )
             }) %>% bind_rows(),
      error = function(e) NULL
    )
  })
  
  output$plot <- renderPlot({
    req(plotData())
    plotData() %>% ggplot() + 
      geom_line(aes(x = X, y = Y, colour = as.factor(Scenario))) +
      theme(legend.title=element_blank())
  })
  
}

shinyApp(ui, server)

renderUImat3 的调用中,您定义了 nrow = 1,每次重新渲染 matrixInput 时都会考虑到这一点。

您需要删除此参数以允许添加行。

正如您现在可能知道的那样,一般来说,我建议放弃那些 renderUI 电话。 我会在应用程序启动时渲染 matrixInputs 并通过 updateMatrixInput 修改它们 - 这样速度更快并且在 UI 和服务器之间保持清晰的分离。

library(ggplot2)
library(shiny)
library(shinyMatrix)

interpol <- function(a, b) { # [a] = modeled periods, [b] = matrix inputs
  c <- b
  c[,1][c[,1] > a] <- a
  d <- diff(c[,1, drop = FALSE])
  d[d <= 0] <- NA
  d <- c(1,d)
  c <- cbind(c,d)
  c <- na.omit(c)
  c <- c[,-c(3),drop=FALSE]
  e <- rep(NA, a)
  e[c[,1]] <- c[,2]
  e[seq_len(min(c[,1])-1)] <- e[min(c[,1])]
  if(max(c[,1]) < a){e[seq(max(c[,1]) + 1, a, 1)] <- 0}
  e <- approx(seq_along(e)[!is.na(e)], e[!is.na(e)], seq_along(e))$y # Interpolates
  return(e)
}

ui <- fluidPage(
  uiOutput("slider"),
  h5(strong("Matrix 1:")), uiOutput("mat1"),
  h5(strong("Matrix 2:")), uiOutput("mat2"),
  h5(strong("Matrix 3:")), uiOutput("mat3"),
  plotOutput("plot")
)

server <- function(input, output, session){
  
  output$slider <- renderUI({sliderInput('periods', 'Modeled periods (X):', min=1, max=10, value=10)})
  
  output$mat1 <- renderUI({
    matrixInput("matrix1", 
                value = matrix(c(5), 1, 1, dimnames = list("Base rate (Y)",NULL)),
                rows =  list(extend = FALSE, names = TRUE),
                cols =  list(names = FALSE),
                class = "numeric")    
  })
  
  output$mat2 <- renderUI({
    req(input$periods)
    req(input$matrix1)
    matrixInput("matrix2",
                value = matrix(c(input$periods, input$matrix1[1,1]), 1, 2, dimnames = list(NULL,c("X","Y"))),
                rows = list(extend = TRUE, names = TRUE, delete = TRUE),
                class = "numeric")
  })
  
  output$mat3 <- renderUI({
    req(input$matrix2)
    matrixInput("matrix3",
                value = matrix(c(input$matrix2[,1], input$matrix2[,2]), ncol = 2, dimnames = list(NULL, rep("Scenario 1", 2))),
                rows = list(extend = TRUE, delta = 1, names = TRUE, delete = TRUE),
                cols = list(extend = TRUE, delta = 2, names = TRUE, delete = TRUE, multiheader = TRUE),
                class = "numeric")
  })
  
  observeEvent(input$matrix2, { 
    if(any(rownames(input$matrix2) == "")){
      tmpMatrix <- input$matrix2
      rownames(tmpMatrix) <- paste("Row", seq_len(nrow(input$matrix2)))
      isolate(updateMatrixInput(session, inputId = "matrix2", value = tmpMatrix))
    }
    input$matrix2
  })
  
  observeEvent(input$matrix3, {
    if(any(colnames(input$matrix3) == "")){
      tmpMatrix <- input$matrix3
      colnames(tmpMatrix) <- paste("Scenario",rep(1:ncol(tmpMatrix),each=2,length.out=ncol(tmpMatrix)))
      isolate(updateMatrixInput(session, inputId = "matrix3", value = tmpMatrix))
    }
    input$matrix3
  })
  
  plotData <- reactive({
    req(input$periods)
    tryCatch(
      lapply(seq_len(ncol(input$matrix3)/2), # column counter to set matrix index as it expands
             function(i){
               tibble(
                 Scenario = colnames(input$matrix3)[i*2-1],
                 X = seq_len(input$periods),
                 Y = interpol(input$periods,input$matrix3[,(i*2-1):(i*2), drop = FALSE])
               )
             }) %>% bind_rows(),
      error = function(e) NULL
    )
  })
  
  output$plot <- renderPlot({
    req(plotData())
    plotData() %>% ggplot() + 
      geom_line(aes(x = X, y = Y, colour = as.factor(Scenario))) +
      theme(legend.title=element_blank())
  })
  
}

shinyApp(ui, server)