A spiral is defined as:
...a curve formed by a point moving around a fixed point and constantly moving away from or approaching the fixed point.
(p110. HBJ Dictionary of Mathematics compiled by Ken Klaebe)
Consider the following RECURSIVE procedures:
TO SPIR1 :A IF 200 < :A [STOP] FD :A RT 45 SPIR1 :A + 1 END TO SPIR2 :A :ANG IF 200 < :A [STOP] FD :A RT :ANG SPIR2 :A + 1 :ANG END TO SPIR3 :A :ANG IF 200 < :A [STOP] FD :A RT :ANG SPIR3 :A + 10 :ANG END TO SPIR4 :A :B FD 30 RT :A SPIR4 :A + :B :B END
Experiment, alter the variables and see what conclusions you can come to.
How did your resultant figures fit with the definition above?
How wide a range of spirals can you now draw?
In your research see if you can model two important geometric figures - the Archimedean and equiangular spirals?
On another theme, you might like to consider the remaining wallpaper patterns. Like the patterns given in previous months, they build on the freize patterns that went before, in that they are obtained from them by introducing a reflection or glide or both. As before each is described according to an international system of coding.
Can you use some elegant programming to replicate these patterns (or with a much more flamboyant motif) and so study this 'small' set of patterns yet further.