function(input, output, session) {
# Combine the selected variables into a new data frame
selectedData <- reactive({
iris[, c(input$xcol, input$ycol)]
})
clusters <- reactive({
kmeans(selectedData(), input$clusters)
})
output$plot1 <- renderPlot({
palette(c("#E41A1C", "#377EB8", "#4DAF4A", "#984EA3",
"#FF7F00", "#FFFF33", "#A65628", "#F781BF", "#999999"))
par(mar = c(5.1, 4.1, 0, 1))
plot(selectedData(),
col = clusters()$cluster,
pch = 20, cex = 3)
points(clusters()$centers, pch = 4, cex = 4, lwd = 4)
})
}
# k-means only works with numerical variables,
# so don't give the user the option to select
# a categorical variable
vars <- setdiff(names(iris), "Species")
pageWithSidebar(
headerPanel('Iris k-means clustering'),
sidebarPanel(
selectInput('xcol', 'X Variable', vars),
selectInput('ycol', 'Y Variable', vars, selected = vars[[2]]),
numericInput('clusters', 'Cluster count', 3, min = 1, max = 9)
),
mainPanel(
plotOutput('plot1')
)
)