Keywords: Archimedean-involute-circle-spirals-comparison.svg Comparison of the Archimedean spiral generated by the equations <tt>x θcosθ</tt> and <tt>y θsinθ</tt> with the Involute of a circle generated by the equations <tt>x cosθ+θsinθ</tt> and <tt>y sinθ-θcosθ</tt> where θ is an angle expressed in radians The Archimedean spiral is shown in red and corresponds to the values <tt>0 �� θ �� 8� </tt> of the angle parameter while the Involute of the circle is shown in black and corresponds to the values <tt>0 �� θ �� 17� /2</tt> of the angle parameter The x-axis extends from -25 to +28 and the y-axis from -26 4 to +23 4 and there are tick marks at -20 -10 +10 +20 along the axes The curves are 1 unit apart at their start points while they are slightly more than 1 5 and slightly less than � /2 units apart where they intersect the x-axis for the final time in this plot Self-made graphic converted from the following vector PostScript source code <pre> 300 396 translate 10 dup scale 6 setgray 3 setlinewidth -25 0 moveto 28 0 lineto stroke 0 -26 4 moveto 0 23 4 lineto stroke 0 setgray/radians 57 2957795131 def/q 2 div/x exch def/c x cos def/s x sin def/x x radians div def def 1 setlinejoin 1 0 moveto 1 1 3060 q c x s mul add s x c mul sub lineto for stroke 1 0 0 setrgbcolor 0 0 moveto 1 1 2880 q x c mul x s mul lineto for stroke showpage EOF</pre> 2012 AnonMoos Archimedean spirals Involute Images with PostScript source code Spirals |