本练习的目的是允许用户根据输入比较两种不同的模型。为此，我创建了一个操作按钮，要求用户指定他们的基本模型，以及一个重置按钮，该按钮在添加基线之前将数据集恢复。 ＆＃34;基地＆＃34;逻辑确定用户是否希望包含基数。
单击添加基线操作按钮后，将保存data.frame的当前状态，并使用＆＃34; baseline＆＃34;重命名分组变量。在它之前添加（使用粘贴）。用户可以选择与此静态基础进行比较的不同模型。
由于某种原因，我无法获得观察事件来更改数据集。 observe事件创建基线数据集很好（用print（）测试），但if（）函数不会改变＆＃34;数据＆＃34;因此停止添加到ggplot的基础。代码是这样编写的，原因有两个。 1）通过在观察事件之后包括if（）函数，对数据的任何进一步更改仅改变＆＃34;数据＆＃34;，然后将其添加到未改变的基线数据。 2）还允许创建重置按钮，该按钮仅在重新绑定之前将data.frame重置为。
这个小问题激怒了我，我无法看到我的错误。为人们提供的任何帮助提前干杯。有简单的方法可以做到这一点（对建议开放），但虹膜数据只是函数的一个例子，实际版本更复杂。
library("ggplot2")
if (interactive()) {
ui <- fluidPage(
selectInput("rows", label = h3("Choose your species"),
choices = list("setosa", "versicolor", "virginica")
),
actionButton("base", "Create baseline"),
actionButton("reset", "Reset baseline"),
plotOutput(outputId = "plot")
) # close fluid page
server <- function(input, output) {
output$plot <- renderPlot({ # create plot
base <- "no" # create baseline indicator which we can change once the observeevent below is changed
data <- iris
data <- iris[which(data$Species == input$rows),] # Get datasubset based on user input
observeEvent(input$base, { # If base is Pressed, run code below:
baseline <- data # Make Baseline Data by duplicating the users' specification
baseline$Species <- paste("Baseline",
data$Species, sep = "_") # Rename the grouping variable to add Baseline B4 it
base <- "yes" # Change our indicator of whether a baseline had been made to yes
}) # Close observe Event
observeEvent(input$reset, {
base <- "no" # This is placed before the rbind so that if we want to reset it will stop the merging of the two dataframes before it happens.
})
if (base == "yes") {
data <- rbind(data, baseline) # Run once the observe event has changed baseline to yes.This is kept seperatel that way any subsequent changes to data will not effect
# the final data. This command will simple add the base onto the changed "data" before plotting
}
observeEvent(input$reset, {
base <- "no"
})
ggplot(data, aes(x=Petal.Width, y = as.numeric(Sepal.Width), colour = Species)) + # variable = each dataset selected, value = respective values for that model
labs(x="Hypothetical X", y="Hypothetical X") +
geom_line()
}) # Close Render Plot
} # Close Serve Function
shinyApp(ui, server)
}
library(shiny)
library(ggplot2)
library("tidyr")
library("dplyr")
library("data.table")
# Lets make a fake dataset called "Data". Has 4 variable options and
the Ages each data point relates to.
Ages <- 1:750
Variable1 <- rnorm(n=750, sd = 2, mean = 0)
Variable2 <- rnorm(n=750, sd = 1, mean = 2)
Variable3 <- rnorm(n=750, sd = 8, mean = 6)
Variable4 <- rnorm(n=750, sd = 3, mean = 3)
Data <- as.data.frame(cbind(Ages, Variable1, Variable2, Variable3,
Variable4) )
### UI
ui <- fluidPage(
checkboxGroupInput(inputId = "columns",
label = h4("Which Variables would you like in your
model?"), # Input Checkbox
choices = c("Variable1", "Variable2", "Variable3",
"Variable4")),
plotOutput(outputId = "plot"),
# Lets have our plot
actionButton("base", "Create baseline"),
# Baseline action
actionButton("reset", "Reset baseline") # Reset Action
) # Close UI
server <- function(input, output) {
output$plot <- renderPlot({
validate(need(!is.null(input$columns), 'Please tick a box to show a
plot.')) # Place a please choose columns for null input
data <- gather(select(Data, "Ages", input$columns), variable, value, -
Ages) ## Just doing a little data manipulation to change from wide to
long form. This allows for calculations down the track and easier
plotting
# Now we can modify the data in some way, for example adding 1. Will
eventually add lots of model modifications here.
data$value <- data$value + 1
rVals <- reactiveValues() # Now we create the reactive
values object
rVals[['data']] <- data # Making a reactive values
function. Place Data as "data".
observeEvent(input$base,{
baseline <- data
baseline$variable <- paste("Baseline",
baseline$variable, sep = "_")
# Rename Variables to Baseline preamble
rVals[['baseline']] <- baseline
# Put the new data into the reactive object under "baseline"
})
observeEvent(input$reset,{ # Reset button will wipe the
data
rVals[['baseline']] <- NULL
})
if(!is.null(rVals[['baseline']])) # if a baseline has been .
created, then
{rVals[['final']] <- bind_rows(rVals[['data']], rVals[['baseline']])
# Here we can simply bind the two datasets together if Baseline exists
} else {rVals[['final']] <- rVals[['data']]}
# Otherwise we can use keep it as it is
## Make our Plot !
ggplot(rVals[['final']], aes(x=Ages, y = as.numeric(value), colour =
variable)) + # variable = each dataset selected, value = respective
values for that model
labs(x="Age", y="value") +
geom_line()
}) ## Close the render plot
} ## Close the server
shinyApp(ui, server)
答案 0 :(得分：1)
你有反应表达的观察者，我已经看到这导致我纠正闪亮代码的次数问题。创建反应式表达式（您的绘图函数）和观察者只指定哪个是物种的基线值（字符串）然后将其提供给绘图函数内的过滤数据：
library(shiny)
library(ggplot2)
ui <- fluidPage(
selectInput("rows", label = h3("Choose your species"),
choices = list("setosa", "versicolor", "virginica")
),
actionButton("base", "Create baseline"),
actionButton("reset", "Reset baseline"),
plotOutput(outputId = "plot")
) # close fluid page
server <- function(input, output) {
rVals = reactiveValues()
rVals[['data']] = iris
rVals[['baseline']] = NULL
output$plot <- renderPlot({
# here we duplicate table to manipulate it before rendering
# the reason for duplicate is that you dont want to affect your
# base data as it may be used elsewhere
# note that due to R's copy-on-write this may be expensive operation and
# have impact on app performance
# in all cases using data.table package is recommended to mitigate
# some of the CoW implications
render.data = rVals[['data']][rVals[['data']][['Species']] %in% c(rVals[['baseline']],input$rows),]
# here manipulate render.data
# and then continue with plot
ggplot(data=render.data,
aes(x=Petal.Width, y = as.numeric(Sepal.Width), colour = Species,group=Species)
) +
labs(x="Hypothetical X", y="Hypothetical X") +
geom_line()
})
observeEvent(input$base,{
rVals[['baseline']]=input$rows
})
observeEvent(input$reset,{
rVals[['baseline']]=NULL
})
}
shinyApp(ui, server)