library(rCharts)
p2 <- nPlot(mpg ~ wt, group = 'cyl', data = mtcars, type = 'scatterChart')
p2$xAxis(axisLabel = 'Weight')
p2$chart(size = '#! function(d){return d.gear} !#')
p2$chart(color = c('red', 'green', 'blue'))
p2