I think none of these examples describe a zlib compressed data block inside a binary file that the OP asked about, as all of your examples are e.g. prepending gzip or zip headers.
Greg, is memDecompress what you are looking for? - Murray On Wed, Nov 27, 2013 at 5:22 PM, Dirk Eddelbuettel <e...@debian.org> wrote: > > On 27 November 2013 at 18:38, Dirk Eddelbuettel wrote: > | > | On 27 November 2013 at 23:49, Dr Gregory Jefferis wrote: > | | I have a binary file type that includes a zlib compressed data block > (ie > | | not gzip). Is anyone aware of a way using base R or a CRAN package to > | | decompress this kind of data (from disk or memory). So far I have found > | | Rcompression::decompress on omegahat, but I would prefer to keep > | | dependencies on CRAN (or bioconductor). I am also trying to avoid > | | writing yet another C level interface to part of zlib. > | > | Unless I am missing something, this is in base R; see help(connections). > | > | Here is a quick demo: > | > | R> write.csv(trees, file="/tmp/trees.csv") # data we all have > | R> system("gzip -v /tmp/trees.csv") # as I am lazy here > | /tmp/trees.csv: 50.5% -- replaced with /tmp/trees.csv.gz > | R> read.csv(gzfile("/tmp/trees.csv.gz")) # works out of the box > > Oh, and in case you meant zip file containing a data file, that also works. > > First converting what I did last > > edd@max:/tmp$ gunzip trees.csv.gz > edd@max:/tmp$ zip trees.zip trees.csv > adding: trees.csv (deflated 50%) > edd@max:/tmp$ > > Then reading the csv from inside the zip file: > > R> read.csv(unz("/tmp/trees.zip", "trees.csv")) > X Girth Height Volume > 1 1 8.3 70 10.3 > 2 2 8.6 65 10.3 > 3 3 8.8 63 10.2 > 4 4 10.5 72 16.4 > 5 5 10.7 81 18.8 > 6 6 10.8 83 19.7 > 7 7 11.0 66 15.6 > 8 8 11.0 75 18.2 > 9 9 11.1 80 22.6 > 10 10 11.2 75 19.9 > 11 11 11.3 79 24.2 > 12 12 11.4 76 21.0 > 13 13 11.4 76 21.4 > 14 14 11.7 69 21.3 > 15 15 12.0 75 19.1 > 16 16 12.9 74 22.2 > 17 17 12.9 85 33.8 > 18 18 13.3 86 27.4 > 19 19 13.7 71 25.7 > 20 20 13.8 64 24.9 > 21 21 14.0 78 34.5 > 22 22 14.2 80 31.7 > 23 23 14.5 74 36.3 > 24 24 16.0 72 38.3 > 25 25 16.3 77 42.6 > 26 26 17.3 81 55.4 > 27 27 17.5 82 55.7 > 28 28 17.9 80 58.3 > 29 29 18.0 80 51.5 > 30 30 18.0 80 51.0 > 31 31 20.6 87 77.0 > R> > > Regards, Dirk > > -- > Dirk Eddelbuettel | e...@debian.org | http://dirk.eddelbuettel.com > > ______________________________________________ > R-devel@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-devel > [[alternative HTML version deleted]] ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel