使用 qplot 生成基本图

qplot 旨在与 base r plot() 功能类似，试图总是绘制你的数据而不需要太多的规范。

基本的 qplot

 placeholderCopyqplot(x = disp, y = mpg, data = mtcars)

添加颜色

 placeholderCopyqplot(x = disp, y = mpg, colour = cyl,data = mtcars)

添加更顺畅

 placeholderCopyqplot(x = disp, y = mpg, geom = c("point", "smooth"), data = mtcars)