
I got a little improvement for the Nonagon construction by compass and straight. It is a little bit complex than beofre. Details see the image.
家住蒲汇塘边,闲来打渔为生.大陆帖子常被和谐,所有博客都曾被关闭。此地来偷闲。 My blog were censored or blocked in mainland China. To backup my files, post here.


 It is my pleasure to find a method go beyond 1E-8 for construct Heptagon with classic method. I doubt first if it is possible to use simple method to construct heptagon with relative error less than 1E-8. It seems there is possibility for relative error less than 1E-9. let me try further.
It is my pleasure to find a method go beyond 1E-8 for construct Heptagon with classic method. I doubt first if it is possible to use simple method to construct heptagon with relative error less than 1E-8. It seems there is possibility for relative error less than 1E-9. let me try further. We all know that a curve to two points with same sum of distances is ellipse.
We all know that a curve to two points with same sum of distances is ellipse.
 But how about to 3 points?
But how about to 3 points? 
 When I checked wiki for heptagon construction method, I found there is a method with 10E-7, a very very accuracy and simple method. I try again to find a better accuracy method and did it. the picture show the math principle and detail construction step. the accuracy is 5E-8,about 10 times better.I am sure it is the best one so far.
When I checked wiki for heptagon construction method, I found there is a method with 10E-7, a very very accuracy and simple method. I try again to find a better accuracy method and did it. the picture show the math principle and detail construction step. the accuracy is 5E-8,about 10 times better.I am sure it is the best one so far.