Hi users, I have no clear clue about plotting spatial data. For example, I just have a table with attribute values of each grid cell, such as elevation. Then I have coordinates of the upper left corner in UTM, the number of rows and columns, and grid cell size. How to create spatial plot of elevations for the grid cells, in color ramp? Should I create a spatial grid layer with all the polygons first? Thanks. [[alternative HTML version deleted]]
You will need to coerce your data into a "spatial" kind, as implemented in `sp` or as of late, `sf` packages. You might want to give the vignettes a whirl before you proceed. Roughly, you will have to coerce the data to Spatial* (you could go for a point, raster or grid type, I think) and also specify the projection. Once you have that, plotting should be handled by packages. Here are a few quick links that might come handy: https://cran.r-project.org/web/views/Spatial.html http://www.datacarpentry.org/R-spatial-raster-vector-lesson/10-vector-csv-to-shapefile-in-r/ Cheers, Roman On Mon, Jan 15, 2018 at 11:22 PM, lily li <chocold12 at gmail.com> wrote:> Hi users, > > I have no clear clue about plotting spatial data. For example, I just have > a table with attribute values of each grid cell, such as elevation. Then I > have coordinates of the upper left corner in UTM, the number of rows and > columns, and grid cell size. How to create spatial plot of elevations for > the grid cells, in color ramp? Should I create a spatial grid layer with > all the polygons first? Thanks. > > -- > -- > You received this message because you are subscribed to the ggplot2 > mailing list. > Please provide a reproducible example: https://github.com/hadley/ > devtools/wiki/Reproducibility > > To post: email ggplot2 at googlegroups.com > To unsubscribe: email ggplot2+unsubscribe at googlegroups.com > More options: http://groups.google.com/group/ggplot2 > > --- > You received this message because you are subscribed to the Google Groups > "ggplot2" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to ggplot2+unsubscribe at googlegroups.com. > For more options, visit https://groups.google.com/d/optout. >-- In God we trust, all others bring data. [[alternative HTML version deleted]]
Also note that there is an R-sig-geo mailing list dedicated to this topic. You might also like to look at [1] for more on coordinate projections. [1] https://www.nceas.ucsb.edu/~frazier/RSpatialGuides/OverviewCoordinateReferenceSystems.pdf On Mon, 15 Jan 2018, Roman Lu?trik wrote:> You will need to coerce your data into a "spatial" kind, as implemented in > `sp` or as of late, `sf` packages. You might want to give the vignettes a > whirl before you proceed. > Roughly, you will have to coerce the data to Spatial* (you could go for a > point, raster or grid type, I think) and also specify the projection. Once > you have that, plotting should be handled by packages. > > Here are a few quick links that might come handy: > > https://cran.r-project.org/web/views/Spatial.html > http://www.datacarpentry.org/R-spatial-raster-vector-lesson/10-vector-csv-to-shapefile-in-r/ > > > Cheers, > Roman > > On Mon, Jan 15, 2018 at 11:22 PM, lily li <chocold12 at gmail.com> wrote: > >> Hi users, >> >> I have no clear clue about plotting spatial data. For example, I just have >> a table with attribute values of each grid cell, such as elevation. Then I >> have coordinates of the upper left corner in UTM, the number of rows and >> columns, and grid cell size. How to create spatial plot of elevations for >> the grid cells, in color ramp? Should I create a spatial grid layer with >> all the polygons first? Thanks. >> >> -- >> -- >> You received this message because you are subscribed to the ggplot2 >> mailing list. >> Please provide a reproducible example: https://github.com/hadley/ >> devtools/wiki/Reproducibility >> >> To post: email ggplot2 at googlegroups.com >> To unsubscribe: email ggplot2+unsubscribe at googlegroups.com >> More options: http://groups.google.com/group/ggplot2 >> >> --- >> You received this message because you are subscribed to the Google Groups >> "ggplot2" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to ggplot2+unsubscribe at googlegroups.com. >> For more options, visit https://groups.google.com/d/optout. >> > > > > -- > In God we trust, all others bring data. > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at 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. >--------------------------------------------------------------------------- Jeff Newmiller The ..... ..... Go Live... DCN:<jdnewmil at dcn.davis.ca.us> Basics: ##.#. ##.#. Live Go... Live: OO#.. Dead: OO#.. Playing Research Engineer (Solar/Batteries O.O#. #.O#. with /Software/Embedded Controllers) .OO#. .OO#. rocks...1k
Hi Roman, Thanks for your reply. For the spatial coordinates layer, I just have coordinates of the upper left corner, numbers of rows and columns of the spatial map, and grid cell size. How to create a spatial layer of coordinates from this data? Thanks. On Mon, Jan 15, 2018 at 3:26 PM, Roman Lu?trik <roman.lustrik at gmail.com> wrote:> You will need to coerce your data into a "spatial" kind, as implemented in > `sp` or as of late, `sf` packages. You might want to give the vignettes a > whirl before you proceed. > Roughly, you will have to coerce the data to Spatial* (you could go for a > point, raster or grid type, I think) and also specify the projection. Once > you have that, plotting should be handled by packages. > > Here are a few quick links that might come handy: > > https://cran.r-project.org/web/views/Spatial.html > http://www.datacarpentry.org/R-spatial-raster-vector- > lesson/10-vector-csv-to-shapefile-in-r/ > > > Cheers, > Roman > > On Mon, Jan 15, 2018 at 11:22 PM, lily li <chocold12 at gmail.com> wrote: > >> Hi users, >> >> I have no clear clue about plotting spatial data. For example, I just >> have a table with attribute values of each grid cell, such as elevation. >> Then I have coordinates of the upper left corner in UTM, the number of rows >> and columns, and grid cell size. How to create spatial plot of elevations >> for the grid cells, in color ramp? Should I create a spatial grid layer >> with all the polygons first? Thanks. >> >> -- >> -- >> You received this message because you are subscribed to the ggplot2 >> mailing list. >> Please provide a reproducible example: https://github.com/hadley/devt >> ools/wiki/Reproducibility >> >> To post: email ggplot2 at googlegroups.com >> To unsubscribe: email ggplot2+unsubscribe at googlegroups.com >> More options: http://groups.google.com/group/ggplot2 >> >> --- >> You received this message because you are subscribed to the Google Groups >> "ggplot2" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to ggplot2+unsubscribe at googlegroups.com. >> For more options, visit https://groups.google.com/d/optout. >> > > > > -- > In God we trust, all others bring data. >[[alternative HTML version deleted]]
the latest ggplot from github (to be installed with `devtools:install_github()`) has support for SF objects too, it's a treat! However, sf is not exactly designed for raster data. Of course you can make each of your cells be a square polygon, but it's not the most efficient way for big datasets. For this the `raster` (excellent and rock stable) and `stars` (even more excellent, but in heavy development) can be used. Adriano Fantini 2018-01-15 23:26 GMT+01:00 Roman Lu?trik <roman.lustrik at gmail.com>:> You will need to coerce your data into a "spatial" kind, as implemented in > `sp` or as of late, `sf` packages. You might want to give the vignettes a > whirl before you proceed. > Roughly, you will have to coerce the data to Spatial* (you could go for a > point, raster or grid type, I think) and also specify the projection. Once > you have that, plotting should be handled by packages. > > Here are a few quick links that might come handy: > > https://cran.r-project.org/web/views/Spatial.html > http://www.datacarpentry.org/R-spatial-raster-vector- > lesson/10-vector-csv-to-shapefile-in-r/ > > > Cheers, > Roman > > On Mon, Jan 15, 2018 at 11:22 PM, lily li <chocold12 at gmail.com> wrote: > >> Hi users, >> >> I have no clear clue about plotting spatial data. For example, I just >> have a table with attribute values of each grid cell, such as elevation. >> Then I have coordinates of the upper left corner in UTM, the number of rows >> and columns, and grid cell size. How to create spatial plot of elevations >> for the grid cells, in color ramp? Should I create a spatial grid layer >> with all the polygons first? Thanks. >> >> -- >> -- >> You received this message because you are subscribed to the ggplot2 >> mailing list. >> Please provide a reproducible example: https://github.com/hadley/devt >> ools/wiki/Reproducibility >> >> To post: email ggplot2 at googlegroups.com >> To unsubscribe: email ggplot2+unsubscribe at googlegroups.com >> More options: http://groups.google.com/group/ggplot2 >> >> --- >> You received this message because you are subscribed to the Google Groups >> "ggplot2" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to ggplot2+unsubscribe at googlegroups.com. >> For more options, visit https://groups.google.com/d/optout. >> > > > > -- > In God we trust, all others bring data. > > -- > -- > You received this message because you are subscribed to the ggplot2 > mailing list. > Please provide a reproducible example: https://github.com/hadley/ > devtools/wiki/Reproducibility > > To post: email ggplot2 at googlegroups.com > To unsubscribe: email ggplot2+unsubscribe at googlegroups.com > More options: http://groups.google.com/group/ggplot2 > > --- > You received this message because you are subscribed to the Google Groups > "ggplot2" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to ggplot2+unsubscribe at googlegroups.com. > For more options, visit https://groups.google.com/d/optout. >[[alternative HTML version deleted]]