Exclude data points by click in plotly in a shiny app r - r

Question

I want to exclude certain data points that are selected by the user by clicking, like in this example (but using plotly).
I tried to do it with the code i show below but it doesnt work.
What i'm triying to do is identify the position of the data point and then once i get the position, set the var delete as TRUE if the row_number() is in the set of selected data points and then just filter is delete is TRUE.
I dont know if this is the most effient form to perfom that.
I would appreciate any help or guidance.
library(shiny)
library(plotly)
library(dplyr)
n <- 20
x <- 1:n
y <- cumsum(rnorm(n))
z <- runif(n,10,200)
cat <- sample(letters[1:5],n,replace = TRUE)
delete <- FALSE
df<-data.frame(cat,x,y,z, delete)
ui <- fluidPage(
selectInput("var","var", c("y","z"), "y"),
mainPanel(plotlyOutput("plot")),
verbatimTextOutput("selection"),
actionButton("delete","Delete", style = "display:inline-block;"),
actionButton("reset","Reset", style = "display:inline-block;"),
)
server <- function(input, output, session) {
myData <- reactive({df})
output$plot <- renderPlotly({
plot_ly(myData(),
x = ~x,
y = ~get(input$var),
type = "scatter",
mode = "markers",
text = ~cat,
marker = list(size = 10),
source = "A")
})
p1 <- reactive({
event_data("plotly_click", source = "A")
})
p2 <- reactiveValues(points = c())
observeEvent(p1(),{
p2$points <- c(p2$points,as.list(p1())$pointNumber)
})
observeEvent(input$reset,{
p2$points <- c()
})
output$selection <- renderPrint({ if(length(p2$points+1)<1){"Select data points to delete"}else{(p2$points+1)} })
observeEvent(input$delete,{
myData() <- myData() %>%
mutate(delete = ifelse(row_number() %in% c(p2$puntos+1),TRUE,delete)) %>%
filter(!delete)
})
}
shinyApp(ui, server)

Answer 1

Nice trick with event_data there! I think all that's needing done differently is to make myData$df a named reactiveValue (with one small correction to p2$points lower down). This works for me now:
library(shiny)
library(plotly)
library(dplyr)
n <- 20
x <- 1:n
y <- cumsum(rnorm(n))
z <- runif(n,10,200)
cat <- sample(letters[1:5],n,replace = TRUE)
delete <- FALSE
df<-data.frame(cat,x,y,z, delete)
ui <- fluidPage(
selectInput("var","var", c("y","z"), "y"),
mainPanel(plotlyOutput("plot")),
verbatimTextOutput("selection"),
actionButton("delete","Delete", style = "display:inline-block;"),
actionButton("reset","Reset", style = "display:inline-block;"),
)
server <- function(input, output, session) {
myData <- reactiveValues(df = df)
output$plot <- renderPlotly({
plot_ly(myData$df,
x = ~x,
y = ~get(input$var),
type = "scatter",
mode = "markers",
text = ~cat,
marker = list(size = 10),
source = "A")
})
p1 <- reactive({
event_data("plotly_click", source = "A")
})
p2 <- reactiveValues(points = c())
observeEvent(p1(),{
p2$points <- c(p2$points,as.list(p1())$pointNumber)
})
observeEvent(input$reset,{
p2$points <- c()
})
output$selection <- renderPrint({ if(length(p2$points+1)<1){"Select data points to delete"}else{(p2$points+1)} })
observeEvent(input$delete,{
# browser()
myData$df <- myData$df %>%
mutate(delete = ifelse(row_number() %in% c(p2$points+1),TRUE,delete)) %>%
filter(!delete)
# And clear input?
p2$points <- c()
})
}
shinyApp(ui, server)