Out of curiosity, and considering the bewildering array of projections and grids in use for various mapping purposes, you seem to be saying in your example 2 that the grid coordinates number south to north and east to west. Given scale of the coordinate numbers, would that be a national grid system employed in New Zealnd?
J. W. Dougherty On Mon, 11 May 2020 13:56:49 +1200 "Richard O'Keefe" <rao...@gmail.com> wrote: > Hey, I know that volcano! It's walking distance from the Intermediate > school I attended. > To you it's a plot; to me it's a place. > So I offer you four scenarios. > > 1. You think of it as a place you know and have been. > In that case the "right" orientation is the one that best matches > what you are used to seeing. > For me, that would put the peak on the right of the plot. > > 2. You think of it as a patch in a map. > In that case the "right:" orientation is the one that matches the > map. That would put the peak at the bottom of the plot. > > 3. You think of it as a product of geological processes, and are > perhaps interested in > whether there is any connection between the orientation of the > volcano and the > direction the Auckland hot-spot (currently at White Island) was > moving. In that case you'd choose south-west -> north-east as the > primary axis. (I think. Not really sure.) > > 4. You think of it as a picture, an illustration in a textbook. It > might need to be cropped > vertically so you can fit another illustration on the same page. > For that and > perceptual reasons you want the major linear axis of the image to > be horizontal. > In that case, what we have now is a perfectly reasonable choice. > > "Quality is fitness for use." > > On Sun, 10 May 2020 at 12:44, Michael Sumner <mdsum...@gmail.com> > wrote: > > > > Does anyone know why 'volcano' is oriented as it is? > > > > image(volcano) ## filled.contour is the same > > > > I know it's all arbitrary, but north-up is a pretty solid > > convention. Is there any reason why the classic 'image()' example > > data set would not default to this orientation? > > > > A Google map of the site (in Web Mercator): > > > > https://www.google.com/maps/place/Maungawhau+%2F+Mount+Eden/@-36.8763271,174.7619561,856m/data=!3m1!1e3!4m8!1m2!2m1!1smaungawhau!3m4!1s0x6d0d47db8d7bd1ff:0x8bcffe2a5c7360d2!8m2!3d-36.8666667!4d174.7666667 > > > > > > For image(), the north-up orientation is > > 't(volcano[,ncol(volcano):1])'. > > > > If you are interested in a roughly georeferenced version I have > > code here: > > > > https://gist.github.com/mdsumner/20fe3ffa04421bf8e0517c19085e5fd8 > > > > (Also see fortunes::fortune("conventions") ) > > > > Best, Mike > > > > > > -- > > Michael Sumner > > Software and Database Engineer > > Australian Antarctic Division > > Hobart, Australia > > e-mail: mdsum...@gmail.com > > > > [[alternative HTML version deleted]] > > > > ______________________________________________ > > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > > https://stat.ethz.ch/mailman/listinfo/r-help > > PLEASE do read the posting guide > > http://www.R-project.org/posting-guide.html and provide commented, > > minimal, self-contained, reproducible code. > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html and provide commented, > minimal, self-contained, reproducible code. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.