Multilines graph with uploaded CSV - r

Question

I would like to be able to display a multi-line graph with an imported csv. CSV files contain time series. On import, I would like to be able to choose, knowing that the name of the fields can change according to the CSV, the field representing the X and the one of Y, and define the field containing the ID which will create the various lines. Something like this :
For now, I have this but it's completly wrong
# ui.R
library(shiny)
library(shinydashboard)
library(ggplot2)
shinyUI(
dashboardPage(
dashboardHeader(title ="Sen2extract"),
sidebar <- dashboardSidebar(
sidebarMenu(
menuItem("Chart", tabName = "chart")
)
),
dashboardBody(
tabItem(tabName = "chart",
box(
width = 12, collapsible=FALSE,
fileInput(inputId = "csv_chart", label = "Upload your CSV", multiple = FALSE,
accept = c(".csv", "text/csv", "text/comma-separated-values,text/plan"), width = "300px"),
selectInput("X", label = "Field X :", choices = list("Choice 1" = "")),
selectInput("Y", label = "Field Y :", choices = list("Choice 1" = "")),
selectInput("group", label = "Group by :", choices = list("Choice 1" = ""))
),
box(plotOutput("plot"), width = 12)
)
)
)
)
# server.R
library(shiny)
library(shinydashboard)
library(ggplot2)
shinyServer(function(input, output, session){
output$plot = renderPlot({
data <- read.csv(file = input$csv_chart)
ggplot(data) +
geom_line(mapping = aes(x = input$X, y = input$Y)) +
labs (x = "Years", y = "", title = "Index Values")
})
})

Answer 1

there were several issues with your code and I have a working version below.
The main issue was that you have to read your data within reactive() and then update the selection. Also, to have multiple lines in your graph, you have to add what to group on in ggplot when you define the mapping in aes or in this case aes_string. I chose color as this gives multiple lines colored according to different groups in the chosen column.
library(shiny)
library(shinydashboard)
library(tidyverse)
ui <- dashboardPage(
dashboardHeader(title ="Sen2extract"),
sidebar <- dashboardSidebar(
sidebarMenu(
menuItem("Chart", tabName = "chart")
)
),
dashboardBody(
tabItem(tabName = "chart",
box(
width = 12, collapsible=FALSE,
fileInput(inputId = "csv_chart", label = "Upload your CSV",
multiple = FALSE,
accept = c(".csv",
"text/csv",
"text/comma-separated-values,text/plan"),
width = "300px"),
selectInput("X", label = "Field X:", choices = "Pending Upload"),
selectInput("Y", label = "Field Y:", choices = "Pending Upload"),
selectInput("group", label = "Group by:", choices = "Pending Upload")
),
box(plotOutput("plot"), width = 12)
)
)
)
server <- function(input, output, session){
data <- reactive({
req(input$csv_chart)
infile <- input$csv_chart
if (is.null(infile))
return(NULL)
df <- read_csv(infile$datapath)
updateSelectInput(session, inputId = 'X', label = 'Field X:',
choices = names(df), selected = names(df)[1])
updateSelectInput(session, inputId = 'Y', label = 'Field Y:',
choices = names(df), selected = names(df)[2])
updateSelectInput(session, inputId = 'group', label = 'Group by:',
choices = names(df), selected = names(df)[3])
return(df)
})
output$plot <- renderPlot({
ggplot(data()) +
geom_line(mapping = aes_string(x = input$X, y = input$Y, color=input$group)) +
labs(x = "Years", y = "", title = "Index Values")
})
}
shinyApp(ui = ui, server = server)