How to display ggplot2 on Rshiny main panel - r

The ggplot2 object doesnt display properly in RShiny mainpanel. For recreation, the below code uses iris dataset. Need help
I checked the link - RShiny ggplot2 not showing , but this didnt help. I also ran through https://shiny.rstudio.com/ website, but nothing had explanation with example on how to display the ggplot2 object. I used renderPlot and renderImage functions, but none gave required results.
'''
library(shiny)
library(shinydashboard)
ui <- fluidPage(titlePanel("Sample Shiny"),
navbarPage(
br(),
tabPanel(h4("Iris Data"),
sidebarPanel(
radioButtons("var1",
label = "Choose a FILL field",
choices = c("Species"),
selected = "Species"),
mainPanel(plotOutput("plot",click = "plot_click")))
)
))
server <- function(input, output) {
output$plot <- renderPlot(
{
#browser()
sw <- input$var1
### "a" below is iris dataset which I pass on as input**
ggplot(data = a) +
aes(x = Sepal.Length, fill = sw) +
geom_bar() +
theme_minimal() +
coord_flip()
},width = "auto",height = "auto",res = 72)
}
# Run app ----
shinyApp(ui, server)
'''
I was hoping to see the graph in the middle of mainpanel, but all I see is a small graph with no proper margins.
Expected: (Something like this on RShiny)
Here is what I see now:

input$var1 is a string => use aes_string:
ggplot(data = a) +
aes_string(x = "Sepal.Length", fill = sw) + ......

Related

ggplot not working properly inside eventReactive() in shiny

I wasted hours to find out why my plot is automatically updating itself when I change inputs while it was supposed to wait for the Run button but it simply ignored that step and I ended up finally finding ggplot as the trouble maker!!! This is my minimal code:
library(ggplot2)
library(tidyverse)
varnames <- names(cars)
ui <- fluidPage(
sidebarLayout(
sidebarPanel(
fluidRow(
column(
width = 12,
# Variables Inputs:
varSelectInput("variables", "Select Input Variables", cars, multiple = TRUE),
selectizeInput("outvar", "Select Output Variable", choices = varnames, "speed", multiple = F),
# Run Button
actionButton(inputId = "run", label = "Run")
)
)
),
# Main panel for displaying outputs ----
mainPanel(
plotOutput("plot")
)
)
)
server <- function(input, output, session) {
df <- reactive({
cars %>% dplyr::select(!!!input$variables, input$outvar)
})
plt <- eventReactive(input$run, {
#Just creating lm formula
current_formula <- paste0(input$outvar, " ~ ", paste0(input$variables, collapse = " + "))
current_formula <- as.formula(current_formula)
#Fitting lm
fit <- lm(current_formula, data = df())
pred <- predict(fit, newdata = df())
#Plotting
ggplot(df(), aes(df()[, input$outvar], pred)) +
labs(x = "Observed", y = "Predicted") +
geom_point() +
theme_bw()
#plot(df()[, input$outvar], pred) #This one works fine!!!!
})
output$plot <- renderPlot({
plt()
})
}
# Run the application
shinyApp(ui = ui, server = server)
If you run this, you'll notice that ggplot doesn't care anymore about the Run button after the 1st run and it keeps updating as you change the inputs!! However, if you use the simple base plot function (which I put in a comment in the code) there wouldn't be any problems and that works just fine! Sadly I need ggplot in my app because base plot is ugly. I am seeing suggestion for using isolate() to solve this issue but I have no clue where isolate() should be put to fix my problem also it doesn't make sense to use isolate() when base plot function works fine without it and it's the ggplot that makes the problem. Any explanation would be appreciated.
The issue is that ggplot aesthetics are lazy evaluated. You really want to put symbols into the aes() rather that reactive data values. Change your plotting code to
ggplot(df(), aes(.data[[input$outvar]], pred)) +
labs(x = "Observed", y = "Predicted") +
geom_point() +
theme_bw()
With ggplot you use the .data pronoun to access the current data source rather than trigger the reactive df() object again.

Interactive Bar Chart Using Shiny - Graph changes based on selected columns

I am teaching myself r and shiny and trying to make an interactive bar chart where the user can change the chart based on columns. I keep getting errors with this code. Any help would be appreciated! My data has four columns: v, one, two, three. The first column is characters and the last three are numbers. I want to change the bar chart based on the y axis (columns: one, two and three). Right now, the error I am getting is: missing value where TRUE/FALSE needed.
library(shiny)
library(readr)
library(ggplot2)
data <- read.csv('scoring.csv')
data$v <- as.character(data$v)
ui <- fluidPage(
titlePanel("Scoring"),
sidebarPanel(
selectInput(inputId = "scoring", label = "Select a score:", c("Scoring Method 1", "Scoring Method 2", "Scoring Method 3"))),
mainPanel(
plotOutput(outputId = "bar")
)
)
#browser()
server <- function(input, output) {
new_data <- reactive({
selected_score = as.numeric(input$"scoring")
if (selected_score == "Scoring Method 1"){(data[data$one])}
if (selected_score == "Scoring Method 2"){(data[data$two])}
if (selected_score == "Scoring Method 3"){(data[data$three])}
})
#browser()
output$bar <- renderPlot({
newdata <- new_data()
p <- ggplot(newdata, aes(x=reorder(v, -selected_score), selected_score, y = selected_score, fill=v)) +
geom_bar(stat = 'identity', fill="darkblue") +
theme_minimal() +
ggtitle("Sports")
barplot(p, height = 400, width = 200)
})
}
Run the application
shinyApp(ui = ui, server = server)
You have a few errors in your code. In the server part, please use input$scoring, instead of input$"scoring".
First, in ui selectInput could be defined as
selectInput(inputId = "scoring", label = "Select a score:", c("Scoring Method 1"="one",
"Scoring Method 2"="two",
"Scoring Method 3"="three")))
Second, your reactive dataframe new_data() could be defined as shown below:
new_data <- reactive({
d <- data %>% mutate(selected_score = input$scoring)
d
})
Third, ggplot could be defined as
output$bar <- renderPlot({
newdata <- new_data()
p <- ggplot(newdata, aes(x=v, y = newdata[[as.name(selected_score)]], fill=v)) +
geom_bar(stat = 'identity', position = "dodge", fill="blue") +
theme_bw() +
#scale_fill_manual(values=c("blue", "green", "red")) +
scale_y_continuous(limits=c(0,10)) +
ggtitle("Sports")
p
})
Please note that you had an extra selected_score variable within aes. My suggestion would be to play with it to reorder x, and review some online or youtube videos on R Shiny.

How to make a boxplot for Shiny web page

Good day
I am trying to make a simple boxplot for a shiny web page but for some reason, it is not working.
I did it in markdown using the below code and I got the results I wanted.
ggplot(test, aes(x = Date, y = test$Var1, group = Date)) +
geom_boxplot()
This is what I get in markdown, which is also what I want for the shiny web page
The following code is what I am using for the shiny web page
library(readxl)
library(shiny)
library(ggplot2)
library(dplyr)
ui <- fluidPage(
titlePanel("questionnaire"),
sidebarLayout(
sidebarPanel(
selectInput("question", "Choose a question",
colnames(test))
),
mainPanel(
plotOutput("coolplot")
)
)
)
server <- function(input, output) {
output$coolplot <- renderPlot(
ggplot(test, aes(x = Date, y = input$question, group = Date)) +
geom_boxplot()
)
}
shinyApp(ui = ui, server = server)
As you can see the code I use to create the boxplots here is almost the same as what I used in markdown.
So why do I get this when I run the app?
Any help in fixing this problem will be greatly appreciated!
I had to use the following code to fix my problem
server <- function(input, output) {
output$coolplot <- renderPlot(
ggplot(test, aes(x = Date, y = get(input$question), group = Date)) +
geom_boxplot()
)

Unable to plot stacked barplot using R Shiny

I am new to R Shiny. Actually i have drawn Stacked Barplot using ggplot in my
R code. I want to draw the same using shiny. Below is my R code:
ggplot(data = df, aes(x = OutPut, y = Group, fill = Group)) +
geom_bar(stat = "identity") +
facet_grid(~ Environment)
In my R code it is giving correct results.But i am trying to draw in shiny. Below is my shiny R code.
ui <- fluidPage(theme = shinytheme("lumen"),
titlePanel("Data Analysis"),
selectInput("variable", "Variable:", c("OutPut", "Member", "Levels")),
mainPanel(plotOutput("plot")))
# Define server function
server <- function(input, output){
x = ggplot(data = df, aes(x = variable.names(), y = Group, fill = Group)) +
geom_bar(stat = "identity") +
facet_grid(~ Environment)
plot(x)
}
# Create Shiny object
shinyApp(ui = ui, server = server)
It is throwing an error,here i have created a dropdown box where all the variables have been stored. So when i select one variable, it should plot the Stacked barplot. Could anyone please help me.
Like it was mentioned in the comments, you need to use the rendering functions and actually assign them to the output to get the outputs you need.
I believe an example of using plots in rshiny would help, since it wouldn't make sense to have it in the comments, here it is:
library(shiny)
library(ggplot2)
ui <- fluidPage(titlePanel("Fast Example with mtcars"),
# inputs
selectInput("x", "Choose x:", choices = names(mtcars), selected = 'mpg'),
selectInput("y", "Choose y:", choices = names(mtcars), selected = 'hp'),
selectInput("fill", "Choose fill:", choices = names(mtcars), selected = 'carb'),
mainPanel(
#outputs
h2("Chosen variables are:"),
h4(textOutput("vars")),
plotOutput("plot")))
server <- function(input, output) {
df <- mtcars
# here's how you would use the rendering functions
# notice that I used aes_string
output$plot <- renderPlot({
ggplot(data=df,
aes_string(x= input$x, y= input$y, fill=input$fill)) +
geom_point()
})
output$vars <- renderText(paste0('x: ', input$x, " , ",
'y: ', input$y, " , ",
'fill: ', input$fill))
}
shinyApp(ui = ui, server = server)
The Rshiny tutorial is pretty helpful, you can take a look at it here https://shiny.rstudio.com/tutorial/

rShiny Selecting between different plotting packages

I have a task where i need to build an rShiny app that allows the user to choose which kind of R plotting package is used in-order to display a plot.
Currently the only way i have gotten it to work (semi-decently) is using package specific functions for each package on the server side and using a series of conditional panels on the UI side.
However the problem is that when the user enters the page for the first time then all plots are initialized. Second problem is when the user changes some plot input values and after that chooses another package then the old plot will be displayed until a new plot is created.
Questions:
Is this the only available approach?
I feel that there must be a way to use reactive functions for the package selection?
I feel that it should be possible to use a single rShiny's htmlOutput (or something similar) in the ui and therefore not needing the switchPanel?
I have created a small app to demonstrate my current implementation and both problems:
server.R
library(shiny)
#library(devtools)
#install_github("ramnathv/rCharts")
library(rCharts)
shinyServer(function(input, output) {
names(iris) = gsub("\\.", "", names(iris))
#Render the Generic plot
output$GenericPlot <- renderPlot({
data = iris[0:input$variable,]
plot(data$SepalLength ~ data$SepalWidth)
})
#Render the Polychart plot
output$PolychartPlot <- renderChart({
plotData <- rPlot(SepalLength ~ SepalWidth, data = iris[0:input$variable,], color = 'Species', type = 'point')
plotData$addParams(dom = 'PolychartPlot')
return(plotData)
})
#Render the NDV3 plot
output$NDV3Plot <- renderChart({
plotData <- nPlot(SepalLength ~ SepalWidth, data = iris[0:input$variable,], group = 'Species', type = 'scatterChart')
plotData$addParams(dom = 'NDV3Plot')
return(plotData)
})
})
ui.R
library(shiny)
library(rCharts)
shinyUI(fluidPage(
sidebarLayout(
sidebarPanel(
selectInput("lib", label = "Library:",
choices = list("Generic", "rCharts Polychart", "rCharts NDV3"),
selected = "Generic"
),
numericInput("variable", "Observations:",
min = 5,
max = 150,
value = 10
)
),
mainPanel(
conditionalPanel(
condition = "input.lib == 'Generic'",
h3("Generic plot"),
plotOutput("GenericPlot")
),
conditionalPanel(
condition = "input.lib == 'rCharts Polychart'",
h3("rCharts Polychart plot"),
showOutput("PolychartPlot", "polycharts")
),
conditionalPanel(
condition = "input.lib == 'rCharts NDV3'",
h3("rCharts NDV3 plot"),
showOutput("NDV3Plot", "nvd3")
)
)
)
))
The final version will use a different dataset and more charting packages. The provided code is more of a toy example, with most of the stuff stripped out.
Make a single part in the output part of the app that includes some logic based on the input. For example,
library(shiny)
library(ggplot2)
data(cars)
server <- function(input, output) {output$plot<- renderPlot({
if (input$lib == "base") {
p <- plot(cars$speed, cars$dist)
} else if (input$lib == "ggplot") {
p <- ggplot(cars, aes(x = speed, y = dist)) + geom_point()
}
p
})
}
ui <- fluidPage(
sidebarLayout(
sidebarPanel(
selectInput("lib", "Library: ", choices = list("base", "ggplot"),
selected = "base")
),
mainPanel(plotOutput("plot"))
)
)
shinyApp(ui = ui, server = server)
This provides one plot and as soon as I change the lib option it regenerates.
Found a solution to my problem. The solution is basically to use uiOutput() in the ui.R and move the plotOutput(), showOutput() methods to the server.R.
The solution based on iacobus code:
ui.R
library(shiny)
library(rCharts)
shinyUI(fluidPage(
sidebarLayout(
sidebarPanel(
selectInput("lib", "Library: ", choices = list("base", "ggplot", "Polychart"),
selected = "base")
),
mainPanel(uiOutput("plot"))
)
))
server.R
library(shiny)
library(ggplot2)
library(rCharts)
data(cars)
server <- function(input, output) {
output$plot<- renderUI({
if (input$lib == "base") {
plotOutput("base")
} else if (input$lib == "ggplot") {
plotOutput("ggplot")
} else if (input$lib == "Polychart") {
showOutput("polychart", "polycharts")
}
})
output$base <- renderPlot({
plot(cars$speed, cars$dist)
})
output$ggplot <- renderPlot({
ggplot(cars, aes(x = speed, y = dist)) + geom_point()
})
output$polychart <- renderChart({
p <- rPlot(speed ~ dist, data = cars, type = "point")
p$addParams(dom = 'plot')
p
})
}
The difficulty arose for me, because i assumed that plotOutput(), showOutput() etc methods can only be used in the ui.R. This however is not the case.
EDIT:
It turned out that this was not enough for pollyCharts to work properly along with other rCharts packages.
instead i am using renderUI and rCharts $show to display the chart inline. The following link was helpful for me: https://github.com/ramnathv/rCharts/issues/373. In the ui i'm using htmlOutput

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