I get it. Thank you for the explanation. Edzer Pebesma writes:
> On 03/02/2021 20:14, Julian M. Burgos wrote: >> Although if I use bind_cols the result is not an sf object.... > > right, this is because bind_cols is not a generic (its first argument > is ... , which you can't dispatch on) so doesn't have an associated sf > method. > > dplyr offers a mechanism to work around this by providing an sf method > for dplyr_reconstruct - something we could try, but then the dplyr > authors mention that this is experimental and considered a stop-gap > measure, so that might work now but stop working any time. > > However, > > sf3 <- cbind(st_extract(st1, sf1), st_drop_geometry(sf1)) > > does return an sf object (note the changed order of arguments) > >> Julian M. Burgos writes: >> >>> Thanks Edzer, I should have checked if st_extract kept the order of the >>> rows. In this case, a way to do it more generally is: >>> >>> sf1 <- bind_cols(st_drop_geometry(sf1), >>> st_extract(st1, sf1)) >>> >>> >>> >>> Edzer Pebesma writes: >>> >>>> st_join does a spatial join, which comes at a cost; since st_extract >>>> doesn't change the row order of the sf object, you could as well use >>>> >>>> st_extract(st1, sf1) %>% mutate(nums = sf1$nums) >>>> >>>> On 03/02/2021 17:10, Julian M. Burgos wrote: >>>>> Dear list, >>>>> >>>>> What would be the best way to do a spatial join between a sf object (of >>>>> POINT geometry) and a star object, so the sf object gets the values of >>>>> the corresponding pixels in the star object? I have done using a >>>>> combination of st_join and st_extract, but it feels a bit clunky. Is >>>>> there a better way? >>>>> >>>>> Here is what I have done: >>>>> >>>>> ## -------------------------------------------------------------- >>>>> ## Load a stars object >>>>> st1 <- read_stars(system.file("tif/L7_ETMs.tif", package = "stars")) %>% >>>>> slice(band, 1) >>>>> >>>>> ## Create an sf object >>>>> >>>>> set.seed(100) >>>>> bb <- st_bbox(st1) >>>>> >>>>> sf1 <- tibble(lon = runif(n = 10, min = bb[1], max = bb[3]), >>>>> lat = runif(n = 10, min = bb[2], max = bb[4]), >>>>> nums = 1:10) %>% >>>>> st_as_sf(coords = c("lon", "lat"), crs = st_crs(st1)) >>>>> >>>>> ## Do the spatial join >>>>> >>>>> sf1 <- st_extract(st1, sf1) %>% >>>>> st_join(sf1) >>>>> ## -------------------------------------------------------------- >>>>> >>>>> Thanks, >>>>> >>>>> Julian >>>>> >>>>> -- >>>>> Julian Mariano Burgos, PhD >>>>> Hafrannsóknastofnun, rannsókna- og ráðgjafarstofnun hafs og vatna/ >>>>> Marine and Freshwater Research Institute >>>>> Botnsjávarsviðs / Demersal Division >>>>> Fornubúðir 5, IS-220 Hafnarfjörður, Iceland >>>>> http://www.hafogvatn.is/ >>>>> Sími/Telephone : +354-5752037 >>>>> Netfang/Email: julian.bur...@hafogvatn.is >>>>> >>>>> _______________________________________________ >>>>> R-sig-Geo mailing list >>>>> R-sig-Geo@r-project.org >>>>> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fstat.ethz.ch%2Fmailman%2Flistinfo%2Fr-sig-geo&data=04%7C01%7C%7C3c716a56362547fd736b08d8c8f98e1e%7C8e105b94435e4303a61063620dbe162b%7C0%7C0%7C637480321457517463%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=j7fW5XZ7xsRpbhbcCobcfFdy%2BvZpmnL7OVoA%2FnQoihg%3D&reserved=0 >>>>> >>>> >>>> _______________________________________________ >>>> R-sig-Geo mailing list >>>> R-sig-Geo@r-project.org >>>> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fstat.ethz.ch%2Fmailman%2Flistinfo%2Fr-sig-geo&data=04%7C01%7C%7C3c716a56362547fd736b08d8c8f98e1e%7C8e105b94435e4303a61063620dbe162b%7C0%7C0%7C637480321457517463%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=j7fW5XZ7xsRpbhbcCobcfFdy%2BvZpmnL7OVoA%2FnQoihg%3D&reserved=0 >> >> -- >> Julian Mariano Burgos, PhD >> Hafrannsóknastofnun, rannsókna- og ráðgjafarstofnun hafs og vatna/ >> Marine and Freshwater Research Institute >> Botnsjávarsviðs / Demersal Division >> Fornubúðir 5, IS-220 Hafnarfjörður, Iceland >> http://www.hafogvatn.is/ >> Sími/Telephone : +354-5752037 >> Netfang/Email: julian.bur...@hafogvatn.is >> -- Julian Mariano Burgos, PhD Hafrannsóknastofnun, rannsókna- og ráðgjafarstofnun hafs og vatna/ Marine and Freshwater Research Institute Botnsjávarsviðs / Demersal Division Fornubúðir 5, IS-220 Hafnarfjörður, Iceland www.hafogvatn.is Sími/Telephone : +354-5752037 Netfang/Email: julian.bur...@hafogvatn.is _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo