Question

我正在尝试制作一个Shiny应用程序，其中用户提供预算约束，该约束形成最大化蛋白质的最优化方程式（通过lpsolve包），并且优化方程式显示在蛋白质重的食物图表中（ x轴）与服务/周（y轴）。

当我运行当前代码时，会弹出侧面板，但主面板中的图形不会出现。如果我删除了renderPlot（）函数，图形将显示，但不是交互式的。

server.R ：

<script>
    function changeBackground(){
        document.body.background = "<?=$varImage;?>";
    }
</script>

ui.R ：

shinyServer(
  function(input, output) {

# user inputs max amt spent on food/wk
budget <- reactive({
  as.numeric(input$budget)
})

output$myPlot <- renderPlot({

# set up optimization eq maximizing protein given constraints
  maxProt <- lp("max",
                SNAP2$protPerServ,
                rbind(SNAP2$fatPerServ, SNAP2$fatPerServ, SNAP2$costPerServ, SNAP2$sodiumPerServ, SNAP2$fiberPerServ, SNAP2$sugarPerServ, SNAP2$calsPerServ, SNAP2$calsPerServ, SNAP2$fruit, SNAP2$vegs, SNAP2$grains, SNAP2$grains, SNAP2$meatProtein, SNAP2$dairy),
                c("<=", ">=", "<=", "<=", ">=", "<=", ">=", "<=", ">=", ">=", ">=", "<=", ">=", ">="),
                c(245, 140, budget(), 16100, 217, 262.5, 12600, 17850, 16, 28, 9, 25, 6.4, 24))

# drop any variables that have a 0 coefficient in the model
  maxProtVec <- maxProt$solution
  x <- data.frame(SNAP2$food, SNAP2$foodGroup, SNAP2$protPerServ, maxProtVec)
  x <- x[!(x$maxProtVec == 0),]
  x <- droplevels(x)

# plot the optimization equation, i.e. food on x-axis and no. servings
# of each food on y-axis
  myPlot <- x %>%
    ggvis(~SNAP2.food, ~maxProtVec, fill = ~SNAP2.foodGroup) %>%
    layer_points(size := "400", opacity := "0.8") %>%
    add_axis("x", title = "", ticks = 14) %>%
    add_axis("y", title = "Servings Per Week") %>%
    bind_shiny("myPlot", "plot_ui")

    })
})

反应性/ renderPlot（）在ggvis + Shiny中不起作用

0 个答案: