R Under development (unstable) (2023-08-09 r84924 ucrt) -- "Unsuffered Consequences" Copyright (C) 2023 The R Foundation for Statistical Computing Platform: x86_64-w64-mingw32/x64 R is free software and comes with ABSOLUTELY NO WARRANTY. You are welcome to redistribute it under certain conditions. Type 'license()' or 'licence()' for distribution details. R is a collaborative project with many contributors. Type 'contributors()' for more information and 'citation()' on how to cite R or R packages in publications. Type 'demo()' for some demos, 'help()' for on-line help, or 'help.start()' for an HTML browser interface to help. Type 'q()' to quit R. > suppressPackageStartupMessages(library(stars)) > > s5p = system.file("sentinel5p/S5P_NRTI_L2__NO2____20180717T120113_20180717T120613_03932_01_010002_20180717T125231.nc", package = "starsdata") > if (s5p != "") { + + lat_ds = paste0("HDF5:\"", s5p, "\"://PRODUCT/latitude") + lon_ds = paste0("HDF5:\"", s5p, "\"://PRODUCT/longitude") + nit_ds = paste0("HDF5:\"", s5p, "\"://PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/nitrogendioxide_summed_total_column") + lat = read_stars(lat_ds) + lon = read_stars(lon_ds) + nit = read_stars(nit_ds) + nit[[1]][nit[[1]] > 9e+36] = NA + + ll = setNames(c(lon, lat), c("x", "y")) + nit.c0 = st_as_stars(nit, curvilinear = ll) + + # more direct method: + nit.c = read_stars(s5p, sub = "//PRODUCT/SUPPORT_DATA/DETAILED_RESULTS/nitrogendioxide_summed_total_column", + curvilinear = c("//PRODUCT/longitude", "//PRODUCT/latitude"), driver = NULL) + if (inherits(nit.c[[1]], "units")) + nit.c[[1]] = units::drop_units(nit.c[[1]]) + nit.c[[1]][nit.c[[1]] > 9e+36] = NA + all.equal(nit.c0, nit.c) + st_crs(nit.c) = 4326 + print(nit.c) + + if (FALSE && capabilities()["png"]) { + png("nit1.png", 800, 800) + plot(nit.c, breaks = "equal", reset = FALSE, axes = TRUE, as_points = TRUE, pch = 16) + maps::map('world', add = TRUE, col = 'red') + dev.off() + + png("nit2.png", 800, 800) + plot(nit.c, breaks = "equal", reset = FALSE, axes = TRUE, as_points = FALSE, border = NA) + maps::map('world', add = TRUE, col = 'red') + dev.off() + + nit.c = stars:::st_downsample(nit.c, 8) + print(nit.c) + + png("nit3.png", 800, 800) + plot(nit.c, breaks = "equal", reset = FALSE, axes = TRUE, as_points = TRUE, pch = 16) + maps::map('world', add = TRUE, col = 'red') + dev.off() + + png("nit4.png", 800, 800) + plot(nit.c, breaks = "equal", reset = FALSE, axes = TRUE, as_points = FALSE, border = NA) + maps::map('world', add = TRUE, col = 'red') + dev.off() + } + + } > > proc.time() user system elapsed 0.76 0.15 0.92