Boost C++ Libraries: Ticket #6019: Convex hull and Area, combined, sometimes give wrong result

attachment set

Thu, 13 Oct 2011 14:47:11 GMT

attachment → boost_geom_test.cpp

status changed; resolution set

Barend Gehrels — Sat, 14 Jan 2012 14:49:03 GMT

status new → closed
resolution → worksforme

I've the opinion the program is changed in between. It now gives 5406, which is correct or at least near the correct value (but it still might be that you expect 5407.5).

Can you make your comment and the program consistent?

status changed; resolution deleted

Barend Gehrels — Sat, 14 Jan 2012 14:49:23 GMT

status closed → reopened
resolution worksforme

anonymous — Mon, 16 Jan 2012 11:53:52 GMT

Sorry, "1407.5" and "1406" were typos which I managed to copy to the bug report - should have read 5407.5 and 5406 respectively.

The correct answer is 5407.5.

The answer the program gives is 5406.

The answer the program gives if all except the three points on the hull are deleted, is 5407.5.

Crispin — Tue, 24 Jan 2012 15:16:44 GMT

I don't know whether it might work if run as a multi point instead, now that bug has been fixed. The list of points in the example is certainly an odd shape for a polygon, I don't know what assumptions the polygon model is built on?

status changed; resolution set

Barend Gehrels — Sun, 05 Feb 2012 16:41:35 GMT

status reopened → closed
resolution → fixed

OK, thanks for answering. There was indeed a problem if there were multiple left-most points, which was the case here. Fixed now. Thanks for your report.

Barend Gehrels — Sun, 05 Feb 2012 17:13:37 GMT

To be complete, also in this test the next include should be added.

#include <boost/geometry/geometries/point_xy.hpp>