You should treat the different sets of coordinates (from Zone 11 and Zone 12) completely separately. You cannot have mixed crs (of projected coordinates) in a dataset. When you plot in R (generally, even with popular spatial formats) there is no account taken of crs, the graphics doesn't know that you plot Zone 11 and then (say) add coordinates from Zone 12, they will be "shifted" as you say. (There are exceptions to this plotting rule but apart from ggplot2::coord_sf they are in dusty corners not front and centre of plotting code in R).
Some level of coordinate hackery (arithmetic shifting) *can work* in limited circumstances, but I would highly recommend against that. Separate your coordinates into two objects, set the source crs appropriately of the zone for each, transform each to a common crs. (UTM is generally a bad idea but comes with a very popular usage culture which is a shame, there's no single right choice but you always need to put thought into the overall region of your data, the properties of the coordinate space that make sense for your work, and whether you will need smaller or larger regions in the future for related work ... I would advise a common crs that is *not UTM* but advice there really depends on the details of your situation). It's hard to be more specific without details of your flow, e.g. code examples. HTH, Mike On Mon, Aug 7, 2023 at 6:23 AM Jason Edelkind via R-sig-Geo < r-sig-geo@r-project.org> wrote: > hello, first time user here and aspiring grad student. I have a set of > location data that I’ve been trying to import into google earth engine from > R as a CSV file. The problem is that about half of my data is from utm zone > 12, and the other half is from utm zone 11. When I import my original data > into google earth engine, the zone 11 data is shifted over to the right > because I use utm zone 12 as the crs in R. After some reading into the > definition of a utm zone, I tried to just subtract 6 from the zone 11 > latitude values after first converting them to a lon/lat format. This > appears to have worked as on first glance all of the zone 11 points are > where they should be, however it feels like too easy a fix for me after > struggling with this for several days. So my question is, is this an > acceptable way to convert my data, or am I doing something wrong that could > result in inaccurate location data? Thanks! > _______________________________________________ > R-sig-Geo mailing list > R-sig-Geo@r-project.org > https://stat.ethz.ch/mailman/listinfo/r-sig-geo > -- Michael Sumner Software and Database Engineer Australian Antarctic Division Hobart, Australia e-mail: mdsum...@gmail.com [[alternative HTML version deleted]] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
