Fred
2004-Jul-29 20:08 UTC
[R] Any orthnormal matrix can keep the curve's shape and size unchnaged?
Dear R users, I want to know, given a curve f in d-dimensional space, It is possible to keep the curve’s shape and size unchanged by an arbitrary dxd orthnormal matrix A? That is, the new curve g = A*f is still the same shape and size as f? Thanks for your advices and answers. Fred [[alternative HTML version deleted]]
Giovanni Petris
2004-Jul-29 22:08 UTC
[R] Any orthnormal matrix can keep the curve's shape and size unchnaged?
Any orthogonal transformation preserves angles between vectors and their length. Therefore, I guess shape and size are preserved -- of course a precise answer depends on how you define these two features of a curve. I am missing what has all this to do with R, though. Giovanni> Date: Thu, 29 Jul 2004 15:08:52 -0500 > From: Fred <fzh113 at hecky.it.northwestern.edu> > Sender: r-help-bounces at stat.math.ethz.ch > Cc: > Importance: Normal > Precedence: list > > Dear R users, > > I want to know, given a curve f in d-dimensional space, > It is possible to keep the curve?s shape and size unchanged by > an arbitrary dxd orthnormal matrix A? > That is, the new curve g = A*f is still the same shape and size as f? > > Thanks for your advices and answers. > > > Fred > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at stat.math.ethz.ch mailing list > https://www.stat.math.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html > > >-- __________________________________________________ [ ] [ Giovanni Petris GPetris at uark.edu ] [ Department of Mathematical Sciences ] [ University of Arkansas - Fayetteville, AR 72701 ] [ Ph: (479) 575-6324, 575-8630 (fax) ] [ http://definetti.uark.edu/~gpetris/ ] [__________________________________________________]