Could it be that the one angle is north-based, the other one east-based?
----- Original Message ----- From: Graham Hardman <gra...@gh-designs.net> To: SQLite mailing list <sqlite-users@mailinglists.sqlite.org> Sent: Thursday, November 29, 2018, 12:46:05 Subject: [sqlite] function named geopolyCosine is a misnomer Hi, I was very interested in the numerical approximation used in the function named geopolyCosine and after a bit of on-line research decided to test it's accuracy myself. What I discovered was that the function in fact returns the sin value rather than the cosine value. This is quickly noticed by checking the return value when r = 0. The value returned is 0 rather than the expected 1.0 The function is only employed by the geopoly_regular function which I found does actually return the expected shape (taking into account the approximation being used). On checking the geopoly_regular program code I saw that the coordinate calculation formulae cancel out the incorrect value returned from geopolyCosine by essentially reversing the normal understanding of sin and cosine. I hope it is understood that I do not wish to offend. I would, in fact appreciate a link to the site where this approximation was discovered. regards, Graham _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users _______________________________________________ sqlite-users mailing list sqlite-users@mailinglists.sqlite.org http://mailinglists.sqlite.org/cgi-bin/mailman/listinfo/sqlite-users
