如何在闪亮的双 Y 轴图形线上添加交互式缩放

Question

我正在尝试在 Shiny 中制作交互式图表，您可以在其中使用滑块更改双 Y 轴图表上其中一条线的缩放值。 Here is what the base graph looks like

我用来在 Shiny 中绘制图表的代码如下，我的目的是将“coeff”变量定义为 UI 中滑块的输入，然后将其合并到如何计算了线的值

###Shiny dual Y axis plot

library(shiny)
library(ggplot2)

ui <- fluidPage(
  titlePanel("Line Graph"),
  sidebarLayout(
    sidebarPanel(
      sliderInput("scalegvt","Scale Government Data by:",  min = 0.03, max = 1.0, value = c(1.0))
    ),
    
    mainPanel(
      plotOutput("distPlot")
    )
  )
)

## Creating server logic
server <- function(input, output) {
  coeff <- reactive({
    req(input$scalegvt)
  })
  output$distPlot <- renderPlot({ #Rendering plot
    compggp <- ggplot(NULL, aes(x = date, y = covid)) +
      geom_spline(data = onsdf, 
                  aes(x = date, y = covid, colour = "ONS Modelled Estimates"), nknots = 90, size = 1.3) +
      geom_spline(data = gvtdf, 
                  aes(x = date, y = covid/coeff, colour = "Gvt Reported Positive Tests"), nknots = 90, 
                  size = 1.3)##This is the section I want to make reactive to "coeff"##
    
    #Stringency bars
    compggp <- compggp + purrr::pmap(strindf, barfunction)
    
    #Adding aesthetics
    compggp <- compggp + scale_x_date(limits = as.Date(c("2020-05-03", NA ))) +
      theme_minimal() +
      scale_y_continuous(labels = scales::comma) +
      labs(x = "Date (year - month)", y = "Covid Cases (estimated and reported)") + 
      scale_y_continuous(labels = scales::comma, name = "Modelled Population Estimates", 
                         sec.axis = sec_axis(~.*coeff, name = "Reported Positive Tests")) +
      scale_colour_manual(name = "",
                          values = c("ONS Modelled Estimates"="khaki4", 
                                     "Gvt Reported Positive Tests" = "darkcyan",
                                     "Lockdown Stringency" = "red"))
    compggp
  })
}

# Running application
shinyApp(ui = ui, server = server)

我实际上并没有从这段代码中收到任何错误消息；滑块和图形都可以正确呈现，但不会相互影响。

非常感谢！

Answer 1

感谢@YBS，coeff()解决了

如何在闪亮的双 Y 轴图形线上添加交互式缩放

How to add interactive scaling on Shiny dual Y axis graph line

r

ggplot2

shiny