Code for the my-classroom Shiny app

app.R

library(shiny)
library(dplyr)
library(ggplot2)
library(babynames)

size <- 25
colors <- c("F" = "#DE94AF", "M" = "#6C939F", "X" = "#D4C62A")

ui <- fluidPage(
   
   titlePanel("My classroom"),
   
   sidebarLayout(
      sidebarPanel(
         sliderInput("year",
                     "The year you were born",
                     min = babynames %>% pull(year) %>% min(),
                     max = babynames %>% pull(year) %>% max(),
                     step=1,
                     sep="",
                     value = 2000),
         actionButton("run","Regenerate"),
         hr(),
         div("Based on data from the United State Social Security Administration. It includes all names that occured at least five times in the year.")
      ),
      
      mainPanel(
         plotOutput("classroom", height="600px")
      )
   )
)

server <- function(input, output) {
   
   output$classroom <- renderPlot({
     input[["run"]]
     babynames %>%
       filter(year == isolate(input[["year"]])) %>%
       sample_n(size - 1, replace=TRUE, weight=n) %>%
       select(sex, name) %>%
       arrange(name) %>%
       mutate(id = row_number()) %>%
       bind_rows(data_frame(id = size/2, sex="X",name="You"),.) %>%
       arrange(id) %>%
       mutate(id = row_number(id),
              y = sqrt(size) - 1 - floor((id-1)/sqrt(size)),
              x = (id - 1) %% (sqrt(size))) %>%
       ggplot(aes(x=x,y=y,label=name))+
       geom_point(size=24, aes(color=sex))+
       geom_text(color = "#404040")+
       scale_color_manual(values=colors)+
       ylim(-1,sqrt(size))+
       xlim(-1,sqrt(size))+
       coord_fixed() +
       theme_void()+
       theme(legend.position = "none")
   })
}

shinyApp(ui = ui, server = server)