Displaying 20 results from an estimated 4000 matches similar to: "maximum elements in an ff object?"
2007 Nov 01
2
unable to install package ff
Hi all,
I've had one of my most miserable R weeks in memory. I'm trying to
deal with huge datasets (>1GB each) but am running up against those
pesky memory limits. The libraries filehash and g.data are not very
suitable for what I need. I haven't gotten into the sql thing yet.
Most recently I've been trying to install the new package ff (not yet
on the CRAN repository). I
2010 Apr 25
4
how to make read in a vector of 0s and 1s with no space between them
Hi all,
Probably a rudimentary question. I have a flat file that looks like
this (the real one has ~10e6 elements):
10110100101001011101011
and I want to pull that into R as a vector, but with each digit being
it's own element. There are no separators between the digits. How can
I accomplish this? Thanks in advance!
Matt
--
Matthew C Keller
Asst. Professor of Psychology
University of
2007 Nov 08
3
skip non-sequential lines using scan?
Hi all,
Is there a way to skip non-sequential lines using the "skip" argument
in the scan function?
E.g., I have a matrix with 100 rows and 1e7 columns. I open a
connection and want to read only lines 5, 7, 9, etc [i.e.,
seq(5,99,2)]
It might seem that the syntax to do this would be something like this
(if only the "skip" allowed vectors in the same way colClasses does in
2011 May 30
3
ideas about how to reduce RAM & improve speed in trying to use lapply(strsplit())
hi all,
I'm full of questions today :). Thanks in advance for your help!
Here's the problem:
x <- c('18x.6','12x.9','302x.3')
I want to get a vector that is c('18x','12x','302x')
This is easily done using this code:
unlist(lapply(strsplit(x,".",fixed=TRUE),function(x) x[1]))
So far so good. The problem is that x is a vector
2011 May 28
3
Changing the name of the "R" process in top
Hi all,
Perhaps this is more of a unix question, but I'll give it a try here.
I am running 9 different R processes at the same time (called from a
shell script using R CMD BATCH). When I use the top program to
monitor how they are doing, it is impossible to tell which R process
is related to which R script. Is there a way to rename a specific
instantiation of an R process in top with
2009 May 20
1
how to get remote ESS graphics to work?
Hi all,
My graduate student is logging onto my macpro and running R through
ESS aquamacs (with Mx ssh and then Mx ess-remote). Everything is
working fine until we get to graphing.
We are trying to give him the ability to look at graphics
interactively. The ESS manual is not too helpful: "If you run X11 (See
Section 13.3.2 [X11], page 68, X-windows) on both the local and remote
machines
2017 Oct 02
2
fwrite() not found in data.table package
Hi all,
I used to use fwrite() function in data.table but I cannot get it to work
now. The function is not in the data.table package, even though a help page
exists for it. My session info is below. Any ideas on how to get fwrite()
to work would be much appreciated. Thanks!
> sessionInfo()
R version 3.2.0 (2015-04-16)
Platform: x86_64-unknown-linux-gnu (64-bit)
Running under: Red Hat
2008 Jul 27
1
64-bit R on Mac OS X 10.5.4
Hi Matt
Your method is the easiest way for me to install the 64-bit R. I followed the directions on your web site and then did the following:
R --arch=x86_64
source("http://bioconductor.org/biocLite.R")
biocLite(type = "source",lib = "/Library/Frameworks/R.framework/Versions/2.8/Resources/RLib64")
I got many errors and warnings which I copied to the attached file.
2008 Jan 15
9
things that are difficult/impossible to do in SAS or SPSS but simple in R
Hi all,
I'm giving a talk in a few days to a group of psychology faculty and
grad students re the R statistical language. Most people in my dept.
use SAS or SPSS. It occurred to me that it would be nice to have a few
concrete examples of things that are fairly straightforward to do in R
but that are difficult or impossible to do in SAS or SPSS. However, it
has been so long since I have used
2009 Jun 17
1
how to interpolate time series data with missingness
Hi all,
I have a vector, most of which is missing. The data is always
increasing, but may do so in jumps. I would like to interpolate the
NAs with 'best guesses', using something like filter(), which doesn't
work due to the NAs. Here is an example:
> x <- c(2,3,NA,NA,NA,3.2,3.5,NA,NA,6,NA)
> x
[1] 2.0 3.0 NA NA NA 3.2 3.5 NA NA 6.0 NA
I would like a function that
2012 Jul 30
1
how to sort huge (> 2^31 row) dataframes quickly
Hello all,
I have some genetic datasets (gzipped) that contain 6 columns and
upwards of 10s of billions of rows. The largest dataset is about 16 GB
on file, gzipped (!). I need to sort them according to columns 1, 2,
and 3. The setkey() function in the data.table package does this
quickly, but of course we're limited by R not being able to index
vectors with > 2^31 elements, and bringing
2012 Feb 21
1
tapply for enormous (>2^31 row) matrices
Hi all,
SETUP:
I have pairwise data on 22 chromosomes. Data matrix X for a given
chromosome looks like this:
1 13 58 1.12
6 142 56 1.11
18 307 64 3.13
22 320 58 0.72
Where column 1 is person ID 1, column 2 is person ID 2, column 3 can
be ignored, and column 4 is how much chromosomal sharing those two
individuals have in some small portion of the chromosome. There are
9000 individual people, and
2007 Oct 21
4
Input appreciated: R teaching idea + a way to improve R-wiki
Hi all,
I will be teaching a graduate-level course on R at CU Boulder next
semester. I have a teaching idea that might also help improve the R
wiki page... I wanted to know what you all thought of it and wanted to
solicit some advice about doing it.
During the latter part of the course, students will choose a topic of
interest (e.g., hierarchical linear modeling), and show how to achieve
it in
2017 Oct 02
0
fwrite() not found in data.table package
You are asking about (a) a contributed package (b) for a package version that is not in CRAN and (c) an R version that is outdated, which stretches the definition of "on topic" here. Since that function does not appear to have been removed from that package (I am not installing a development version to test if it is broken for your benefit), I will throw out a guess that if you update R
2007 Oct 11
1
constraining correlations
Hello,
I've searched for an answer to no avail. I am wondering if anyone
knows how to constrain certain correlations to be equal. I have family
data with 2 twins per family plus up to 2 siblings. I would like to
somehow constrain all the sibling correlations (twin-sib and sib-sib)
to be the same while allowing the twin-twin correlation to be
different. Here is some simulated code:
2009 Mar 11
2
non-positive definite matrix remedies?
Hi all,
For computational reasons, I need to estimate an 18x18 polychoric
correlation matrix two variables at a time (rather than trying to
estimate them all simultaneously using ML). The resulting polychoric
correlation matrix I am getting is non-positive definite, which is
problematic because I'm using this matrix later on as if it were a
legitimately estimated correlation matrix (in order
2010 Feb 06
2
question about bigmemory: releasing RAM from a big.matrix that isn't used anymore
Hi all,
I'm on a Linux server with 48Gb RAM. I did the following:
x <- big.matrix(nrow=20000,ncol=500000,type='short',init=0,dimnames=list(1:20000,1:500000))
#Gets around the 2^31 issue - yeah!
in Unix, when I hit the "top" command, I see R is taking up about 18Gb
RAM, even though the object x is 0 bytes in R. That's fine: that's how
bigmemory is supposed to
2011 Aug 19
1
how to merge distance data based on location
Hi all,
I have two data frames, two columns each, 1000s of rows. Each row
represents a segment of the genome where a deletion has occurred.
First column is start position of the deletion in genomic distance,
second is end position.
So, e.g., first 3 rows of data frame A is:
1003 1023
5932 6120
12348 12689
first 3 rows of data frame B is:
852 5305
1010 1015
8500 9500
10000 13000
I want to merge
2010 Mar 15
2
[R-SIG-Mac] How to interrupt an R process that hangs
+1--this is the single most-annoying issue with R that I know of.
My usual solution, after accomplishing nothing as R spins idly for a couple
hours, is to kill the process and lose any un-saved work. save.history() is
my friend, but is a big delay when you work with big data sets as I do, so I
don't run it after every command.
I have cc'd r-help here, however, because I experience this
2011 May 29
1
why does scan(gzfile("file"), what='integer') import data as mode "character" ?
Hi all,
My code:
x <- scan(gzfile("file"),what='integer')
x is imported, but as mode "character" rather than "integer". I know I
can do as.integer() when importing, but am still trying to figure out
why the above occurs. When I do
summary(as.integer(x)), there are no NAs introduced by coercion, so
the vector really is all integer.
Also, is the above