Subject: Re: [boost] [geometry] area, length, centroid, behavior
From: Mathias Gaunard (mathias.gaunard_at_[hidden])
Date: 2009-02-24 12:37:33


Brandon Kohn wrote:

> I think failing to compile would be the most reasonable. I cannot think
> of any reasonable use-case where one would want the area of a point, or
> a line. I suspect the most often encountered case would be that the user
> has made a logic-error. The same applies to volume (or any integral
> quantity which is a function of dimension). I would suggest that area
> would require a 2D concept and that the shape of the object be at
> minimum a 2-simplex (triangle.. possibly degenerate).

Shapes, volumes, etc. are sets of points.
Various sets have a null area. This is perfectly valid and is not a
logic error.

Points (a point is just a set of points which one element) and lines
have zero area, this is common knowledge. This is even stated in the
definition on "area" on wikipedia, for example.