The polar coordinates and can be converted to the Cartesian coordinates and using the trigonometry functions:

It follows that a figure specified in can be plotted by ‘plot2d’ as a parametric curve:

Fig. 1

It is possible to plot two or more parametric curves together:

Fig. 2 and

An alternate is the ‘draw2d’ function, it draws graphic objects created by the ‘polar’ function:

Fig. 3 and

Fig. 4 shows a graceful geometric curve that resembles a butterfly. Its equation is expressed in polar coordinates by

Fig. 4