Gilles, > I thought that the question was how to replace "transform"...
I should probably clarify. I want to change the name of the Transform class to make it clear that it only represents transforms that preserve parallelism (eg, affine transforms). The most obvious name would be AffineTransform like I suggested but I want to make sure that no one objects to this for design or mathematical reasons. > Anyways, what would be the issue(s) of a non-affine transform? > IOW why should implementations of "Transfrom" be restricted to affine > transform? Instances of Transform are used to transform hyperplanes and hyperplane-bounded regions. If the transform is not affine, then the computed results will not be accurate. -Matt ________________________________ From: Gilles Sadowski <gillese...@gmail.com> Sent: Tuesday, January 7, 2020 6:41 PM To: Commons Developers List <dev@commons.apache.org> Subject: Re: [geometry] Rename Transform to AffineTransform Le mar. 7 janv. 2020 à 17:55, Matt Juntunen <matt.juntu...@hotmail.com> a écrit : > > Gilles, > > > "AffineMap" (?) > > I think any name that doesn't include the word "transform" somehow would > probably be confusing. This is supposed to be a synonym.[1] I thought that the question was how to replace "transform"... > > > Was the same "Transform" interface used in both the "euclidean" and the > "spherical" packages of "Commons Math"? > > Indirectly. SphericalPolygonsSet extended AbstractRegion, which included an > applyTransform(Transform) method. So the "affine" requirement (in the doc) applied there too. Anyways, what would be the issue(s) of a non-affine transform? IOW why should implementations of "Transfrom" be restricted to affine transform? Regards, Gilles [1] https://en.wikipedia.org/wiki/Affine_transformation > -Matt > ________________________________ > From: Gilles Sadowski <gillese...@gmail.com> > Sent: Tuesday, January 7, 2020 10:29 AM > To: Commons Developers List <dev@commons.apache.org> > Subject: Re: [geometry] Rename Transform to AffineTransform > > Hello. > > Le mar. 7 janv. 2020 à 16:00, Matt Juntunen > <matt.juntu...@hotmail.com> a écrit : > > > > Hi all, > > > > The documentation for the o.a.c.geometry.core.Transform interface (which > > comes from the original commons-math version) states that implementations > > must be affine. Therefore, I think we should rename this interface to > > AffineTransform to avoid confusion with other types of transforms, such as > > projective transforms. Potential problems with this are > > - the fact that the JDK already has a class with the same name > > (java.awt.geom.AffineTransform), and > > "AffineMap" (?) > > > - I'm not sure if the term "affine" can technically be applied to > > non-Euclidean geometries, such as spherical geometry (there may be nuances > > there that I'm not aware of). > > Was the same "Transform" interface used in both the "euclidean" and the > "spherical" packages of "Commons Math"? > > Regards, > Gilles > > > Anyone have any insight or opinions on this? I've created GEOMETRY-80 to > > track this issue. > > > > Regards, > > Matt --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org For additional commands, e-mail: dev-h...@commons.apache.org
