Re: [R-sig-Geo] Azimuthal equidistant projection and rgdal

2012-11-13 Thread Ashton Shortridge
Dear Johan (and list), you are right in the first case: I think the result is expected. Using global data with this sort of projection will look kind of awful - the equatorial azimuthal equidistant illustrations in Snyder do not try to map data for the whole planet - they employ a hemisphere.

Re: [R-sig-Geo] Azimuthal equidistant projection and rgdal

2012-11-13 Thread Johan Mazel
Hi I don't think that Synder's book actually use a hemisphere for the azimuthal equidistant projection examples. For example, on figures 41.B and 41.C, you can see Australia (respectively left to top-left and bottom-left). I think that in both cases, you can see the whole world. This is quite

Re: [R-sig-Geo] Azimuthal equidistant projection and rgdal

2012-11-12 Thread Ashton Shortridge
Dear Johan (and list), I'm not a professional cartographer, but I do find myself flipping through Snyder's book of map projections every once in a while. Looking at your results, I don't see anything 'wrong' with the code or the results. Yes, the map looks awful, but that is what it should

Re: [R-sig-Geo] Azimuthal equidistant projection and rgdal

2012-11-12 Thread Johan Mazel
Thanks for your answer. Regarding your last paragraph, I am not really sure to understand. Do you mean that the result is expected in regards to the script (and rgdal use) ? Or do you mean that azimuthal equidistant projection is not possible/valid on any other points than the two poles ?

[R-sig-Geo] Azimuthal equidistant projection and rgdal

2012-10-25 Thread Johan Mazel
Hi I am trying to use the solution rpesented here: https://stat.ethz.ch/pipermail/r-sig-geo/2007-December/002939.html. However it looks like the shifted (from the north pole) map is displayed on top on the original azimuthal equidistant projection centered on the north pole. Is there any way to