В Fri, 25 Apr 2025 13:41:35 +0000 André Wildberg <andre.wildb...@outlook.com> пишет:
> Reproducible example: > > addr <- > "https://www1.ncdc.noaa.gov/pub/data/ghcn/daily/by_station/USW00014839.csv.gz"; > > > # online/stream > > nrow(read.csv(gzcon(url(addr), text=T), header=F)) > > # [1] 1798 > > > # local > > download.file(addr, destfile=basename(addr)) > > nrow(read.csv(gzcon(file(basename(addr), "r"), text=T), header=F)) > > # [1] 429498 I can reproduce the problem (with slightly different numbers): length(readLines(gzcon(file("USW00014839.csv.gz", "rb"), text = TRUE))) # [1] 28002 length(readLines("USW00014839.csv.gz")) # [1] 429535 The underlying reason for the problem you're having with gzcon() is most likely that the gzip archive has been concatenated from multiple separate archives: perl -MIO::Uncompress::Gunzip -E' my $z = IO::Uncompress::Gunzip::->new(shift); say "end of stream" while $z->nextStream() == 1; ' -- USW00014839.csv.gz # end of stream # end of stream # end of stream # end of stream # end of stream readLines("USW00014839.csv.gz") calls file(), which can transparently switch to a gzfile() connection, which supports concatenated archives, but gzcon() currently doesn't. Feature request submitted at <https://bugs.r-project.org/show_bug.cgi?id=18887>. -- Best regards, Ivan ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide https://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
