Initial scaling in shiny - r

Question

I've got a problem using the shiny package in R. I'm trying to insert income. debt and bonus entered in the slider that I've built into the original data set so the algorithm can scale i.e. normalise the data to make the calculation. Right now I can only make the calculation as-is i.e. when you enter the data it calculates it however, as I indicated, I want the data entered to go back into the original data set so I can scale it before making the calculation. I have the below code for the shiny package.
library(shiny)
shinyUI(fluidPage(
headerPanel("Calculating fwbs"),
sidebarPanel(
sliderInput("Income", "Please Select Income: ", min=0, max=5000,
value=2500, step=100),
sliderInput("Debt", "Please Select Debt: ", min = 0, max=2500,
value=1250, step = 100),
sliderInput("Bonus", "Have you received any bonus: ", min=0, max= 1000,
value=500, step =100)
),
mainPanel(
textOutput("fwbi")
)
))
shinyServer(function(input, output, session){
output$fwbi <- renderText({
income2<- input$Income
debt2<- input$Debt
bonus2<- input$Bonus
paste("Your fwbi is: ", income2 + debt2 + bonus2)
})
})
Many thanks

Answer 1

If you want to be able to add an arbitrary number of rows to the original data, you can use a reactiveValues list:
Dframe <- data.frame(income = rnorm(5),
debt = rnorm(5),
bonus = rnorm(5))
library(shiny)
shinyApp(
ui =
shinyUI(
fluidPage(
headerPanel("Calculating fwbs"),
sidebarPanel(
sliderInput("Income", "Please Select Income: ", min=0, max=5000,
value=2500, step=100),
sliderInput("Debt", "Please Select Debt: ", min = 0, max=2500,
value=1250, step = 100),
sliderInput("Bonus", "Have you received any bonus: ", min=0, max= 1000,
value=500, step =100),
actionButton(inputId = "btn_add_to_data",
label = "Add To Data")
),
mainPanel(
textOutput("fwbi"),
tableOutput("data")
)
)
),
server =
shinyServer(function(input, output, session){
# Store the original data at start up.
Data <- reactiveValues(
Source = Dframe
)
# Every time you click "Add Data", it will add the user-input to Data$Source
observeEvent(
input$btn_add_to_data,
{
new_row <- data.frame(income = input$Income,
debt = input$Debt,
bonus = input$Bonus)
Data$Source <- rbind(Data$Source,
new_row)
}
)
output$fwbi <- renderText({
income2<- input$Income
debt2<- input$Debt
bonus2<- input$Bonus
paste("Your fwbi is: ",
scale(Data$Source$income) +
scale(Data$Source$debt) +
scale(Data$Source$bonus))
})
output$data <- renderTable({
Data$Source
})
})
)
If you want to limit the user to only adding one row, you can use an eventReactive
Dframe <- data.frame(income = rnorm(5),
debt = rnorm(5),
bonus = rnorm(5))
library(shiny)
shinyApp(
ui =
shinyUI(
fluidPage(
headerPanel("Calculating fwbs"),
sidebarPanel(
sliderInput("Income", "Please Select Income: ", min=0, max=5000,
value=2500, step=100),
sliderInput("Debt", "Please Select Debt: ", min = 0, max=2500,
value=1250, step = 100),
sliderInput("Bonus", "Have you received any bonus: ", min=0, max= 1000,
value=500, step =100),
actionButton(inputId = "btn_add_to_data",
label = "Add To Data")
),
mainPanel(
textOutput("fwbi"),
tableOutput("data")
)
)
),
server =
shinyServer(function(input, output, session){
NewData <- eventReactive(
input$btn_add_to_data,
{
new_row <- data.frame(income = input$Income,
debt = input$Debt,
bonus = input$Bonus)
rbind(Dframe,
new_row)
}
)
output$fwbi <- renderText({
income2<- input$Income
debt2<- input$Debt
bonus2<- input$Bonus
paste("Your fwbi is: ",
scale(NewData()$income) +
scale(NewData()$debt) +
scale(NewData()$bonus))
})
output$data <- renderTable({
NewData()
})
})
)

Answer 2

We can change the codes to
library(shiny)
library(DT
-create a function
fscale <- function(data = NULL) {
ui <- fluidPage(
headerPanel(title = "Calculating fwbs"),
sidebarPanel(
sliderInput("Income", "Please Select Income: ", min=0, max=5000,
value=2500, step=100),
sliderInput("Debt", "Please Select Debt: ", min = 0, max=2500,
value=1250, step = 100),
sliderInput("Bonus", "Have you received any bonus: ", min=0, max= 1000,
value=500, step =100),
numericInput("n", "Number of rows to scale:", 10, min = 1, max = 100)
),
mainPanel(
textOutput("fwbi"),
dataTableOutput("data"))
)
server <- function(input, output, session){
dat_scale <- reactive({
n1 <- seq_len(input$n)
data[["Income"]][n1] <- (data$Income[n1] - input$Income)/data$Income[n1]
data[["Debt"]][n1] <- (data$Debt[n1] - input$Debt)/data$Debt[n1]
data[["Bonus"]][n1] <- (data$Bonus[n1] - input$Bonus)/data$Bonus[n1]
data
})
output$data <- renderDataTable({
dat_scale()
})
output$fwbi <- renderText({
income2<- input$Income
debt2<- input$Debt
bonus2<- input$Bonus
paste("Your fwbi is: ", income2 + debt2 + bonus2)
})
}
shinyApp(ui= ui, server = server)
}
-run the function
fscale(df1)
-output
data
set.seed(24)
df1 <- data.frame(Income = sample(0:5000, 25, replace = TRUE),
Debt = sample(0:2500, 25, replace = TRUE),
Bonus = sample(0:1000, 25, replace = TRUE))