similar to: Possible bugs in 'seek' and 'readBin'

Hi, I'm running into more issues when reading data from a gzfile connection. If I read the data sequentially with successive calls to readBin(), the data I get looks ok. But if I call seek() between the successive calls to readBin(), I get corrupted data. Here is a (hopefully) reproducible example. See my sessionInfo() at the end (I'm not on Windows, where, according to the man page,

Hi everybody! I've a large dataset, about 2 Mio entries of the format which I would like to import into a frame: <integer><integer><float><string><float><string><string> Because to the huge data amount I've choosen a binary format instead of a text format when exporting from Matlab. My import function is attached below. It works fine for only

Hi, The latest version of R had some changes to functions "readbin() and writeBin() [which] now support raw vectors as well as filenames and connections.". As a result I am working on retiring "raw2bin" and "bin2raw" functions from "caTools" package which do exactly the same. Thanks to Prof. Ripley for bringing this change to my attention. Which brings me

Hello, With the help of "seek" I can start "readBin" from any byte offset within my file that I deem appropriate. What I would like to do is to be able to define the endpoint of that read as well. Is there any solution to that already out there? Thanks for any hints, Joh

R-devel: I am encountering a consistency issue using socketConnection and readBin with *non-blocking* connections on Unix and Windows XP (no Vista to test). I am a bit confused by the behavior of *non-blocking* connections under Windows specifically. When calling readBin on a non-blocking connection when there is no data to read on the socket, the connection under Unix will return a vector of

I have a binary file which is an image with multiple bands, arranged in BSQ format such that R, B and G are all N x M sized matrices (corresponding to Red, Blue and Green colors respectively). The BSQ file arranges the data as [R, B, G], so to access the B matrix, I have to read forward N x M + 1 number of samples. Is there a fast way to define a variable as the B matrix exclusively (e.g. Can I

I think it would be helpful if readBin checked that its endian argument is a legal value. Why? I was reviewing some of our code and noticed that the author had readBin(..., endian="network") and never having heard of "network", I looked at the man page for readBin, and it hadn't heard of "network" either. Not good. I then looked at the R code for readBin, which

Hello, Has a function been built that will skip to a certain bit in a binary file? As of 2009 the answer was 'no': http://r.789695.n4.nabble.com/read-binary-file-seek-td900847.html https://stat.ethz.ch/pipermail/r-help/2009-May/199819.html If you feel I don't need to (like in the links above), please provide some help. (Note this is my first time working with binary files.) I'm

Hi, The man page for readBin has a small typo: --- a/src/library/base/man/readBin.Rd +++ b/src/library/base/man/readBin.Rd @@ -58,7 +58,7 @@ writeBin(object, con, size = NA, endian \code{readBin} and \code{writeBin} read and write C-style zero-terminated character strings. Input strings are limited to 10000 - characters. \code{\link{readChar}} and \code{\code{writeChar}} +

Hello! I have problems with using of "readBin" to read files, which was written in C with "fwrite". In the C-File there is the following Code: fwrite(MyitINI,sizeof(itINItype),1,outfile); where MyitINI is a structure of the following form typedef struct{ int KernelFileSave; /* Determined, if Systemmatrix saved or not.*/ char KernelFileName[200]; /* A-Matrix name

Hi folks: This may be a stupid question, but I cannot seem to find a way to tell readBin that I want to read 2-byte integers from the connection. The input file is 150,720 bytes long containing 75,360 short (2-byte) integers. But specifying "integer" or "int" for what in readBin only returns me a vector of length 37680, leading me to believe that sizeof(integer) or

Dear all, The version of readBin() in R-devel includes a use of match(), through `%in%`, which can affect its performance significantly. By using primitives instead of the rather expensive call to match(), I reduce the time spent inside readBin() by more than 30% in some of my code (part of the tractor.base package). A simple patch that does this is given below. This passes "make

Posting for a friend Begin forwarded message: From: "Geier, Florian" <florian.geier08@imperial.ac.uk<mailto:florian.geier08@imperial.ac.uk>> Subject: Fwd: readBin fails to read large files Date: September 1, 2011 4:10:53 PM GMT+01:00 To: Begin forwarded message: Date: 1 September 2011 16:01:45 GMT+01:00 Subject: readBin fails to read large files Dear all, I am trying

I want to read in a binary file using the readBin() function. In order to skip uninformative parts of the file I use the seek() function, I need to specify the number of bits to skip rather than the number of bytes to skip. E.g. seek(to.read,origin="current",blockSize) with blockSize giving the number of bits Does anybody know if this works? Any help would be highly

Dear all, I'm trying to write an efficient binary file reader for a file type that is made up of several fields of variable length, and so requires many small reads. Doing this on the file directly using a sequence of readBin() calls is a bit too slow for my needs, so I tried buffering the file into a raw vector and reading from that ("loc" is the equivalent of the file pointer):

Dear all, I'm trying to write an efficient binary file reader for a file type that is made up of several fields of variable length, and so requires many small reads. Doing this on the file directly using a sequence of readBin() calls is a bit too slow for my needs, so I tried buffering the file into a raw vector and reading from that ("loc" is the equivalent of the file pointer):

I would like to use readBin to read a binary data file. Most of the data is 4-byte floating point but, for some reason, only double precision appears to be offered. I tried fVariable=readBin(iFile,what=single()); and got 35.87879 which looks believable except that the correct value is 3.030303. I then tried fVariable=readBin(iFile,what=single(),4); and got [1] 3.831111e+10 6.657199e+10

I have been trying to use the gunzip function in the R.utils package. It opens a connection to a gzfile, uses readBin to read from that connection, and then uses writeBin to write out the raw data to a new file. This works as expected under linux/mac, but under Windows, I get: Error in readBin(inn, what= raw(0), size = 1, n=BFR.SIZE) : negative length vectors are not allowed A simple

Hello, I'm wondering if I can get some help with reading Fortran binary "unformatted" output files into R. The Fortran output files were generated in Ubuntu 10.04 LTS using gfortran4.4, on a 32bit Intel Core 2 Duo 3.16 GHz machine, with little-endian and record marker lengths equal to 4. The machine I'm currently trying to read this Fortran output file is a Macbook Pro

Full_Name: Ken Yap Version: 1.6.1 OS: Linux (SuSE 8.0) Submission from: (NULL) (129.78.64.5) I'm trying to copy a file using readBin and writeBin. (The reason is to be able to pipe PostScript or PDF output to a socket later, this is just an experiment.) I do: zz <- file("foo.ps", "rb") r <- readBin(zz, character(), 1000000) yy <- file("bar.ps",