Set marker size in plotly

Question

How can I change the marker size in plotly in R on a map? If I set the size argument to any number it makes it the same, too big size. And if I map it to a vari

Answer 1

The simplest, and probably canonical way is to use the marker.sizeref attribute. You wrap this inside marker=list(...) like this

plot_geo(sample, locationmode='USA-states') %>%
  add_markers(y=~lat, x=~long, hoverinfo="text",
    color=~Group, text=~Group, size=~Value, 
    marker=list(sizeref=0.1, sizemode="area")) %>%
  layout(title='plotly marker map', geo=x)

Note that, the smaller sizeref, the bigger the markers. E.g with sizeref=0.02 we get