Shapes
Shapes, when combined with Geom.point, specify the appearance of markers. Available shapes include circle, square, diamond, cross, xcross, utriangle, dtriangle, star1, star2, hexagon, octogon, hline, and vline.
Examples
plot(dataset("HistData","DrinksWages"),
x="Wage", y="Drinks", shape=[Shape.square],
Geom.point, Scale.y_log10)