Markers
swiss$Catholic.cat <- cut(swiss$Catholic, breaks = c(-Inf, 30, 60, Inf),
c("Low","Middle","High"))
p <- plot_ly(mode = "markers",
type = "scatter",
data = swiss,
x = swiss$Agriculture,
y = swiss$Fertility,
marker = list(color = "black"))
p <- layout(p, showlegend = FALSE)
p