Displaying 20 results from an estimated 1000 matches similar to: "Hand-crafting an .RData file"
2012 Oct 02
1
ffsave problems
Dear R friends.
After having some troubles learning how to create a ffdf object, now I find
myself having problems saving it.
this is the data i´d like to save:
str(DATA)
List of 3
$ virtual: 'data.frame': 6 obs. of 7 variables:
.. $ VirtualVmode : chr "double" "short" "integer" "integer" ...
.. $ AsIs : logi FALSE FALSE FALSE
2010 Dec 24
1
How to specify ff object filepaths when reading a CSV file into a ff data frame.
Hi,
The read.csv.ffdf function in package ff will create the ff object
physical file in the default directories, I am trying to let the files
created in the paths users specify, I think the point is to make use
of the asffdf_args parameter,
I have a test CSV file named D:\rtemp\fftest.csv, the content of the
file is as following:
col1,col2,col3
1,"amber",2.4
2,"linda",4.5
2012 Oct 31
1
ffdfindexget from package ff
I'm having trouble getting ffdfindexget to work right in Windows. Even the
most trivial of examples gives me problems.
> myVec = ff(1:5)
> another = ff(10:14)
> littleFrame = ffdf(myVec, another)
> posVec = ff(c(2, 4), vmode = 'integer')
> ffdfindexget(littleFrame, posVec)
Error in if (any(B < 1)) stop("B too small") :
missing value where TRUE/FALSE
2009 Nov 25
3
questions on the ff package
Hi,
I have two questions on using the ff package and wonder if anyone who used
ff can share some thoughts.
I need to save a matrix as a memory-mapped file and load it back later. To
save the matrix, I use
mat = matrix(1:20, 4, 5)
matFF = ff(mat, dim=dim(mat), filename="~/a.mat", overwrite=TRUE, dimnames
= dimnames(mat))
To load it back, I use
matFF2 = ff(vmode = "double",
2010 Nov 10
1
ff objects saving problem
Hi,
I am running the examples in page 70 of the ff package document, but it failed with the following error
> cat("let's create some ff objects\n")
let's create some ff objects
> n <- 8e3
> a <- ff(sample(n, n, TRUE), vmode="integer", length=n, filename="d:/tmp/a.ff")
> b <- ff(sample(255, n, TRUE), vmode="ubyte", length=n,
2012 Jul 25
3
ff package: reading selected columns from csv
*Dear R users, Ive just started using the ff package.
There is a csv file (~4Gb) with 7 columns and 6e+7 rows. I want to read only
column from the file, skipping the first 100 rows.
Below Ive provided different outcomes, which will clarify my problem
*
> sessionInfo()
R version 2.14.2 (2012-02-29)
Platform: x86_64-pc-mingw32/x64 (64-bit)
locale:
...
attached base packages:
[1] tools
2013 Nov 18
1
Reading in csv data with ff package
I've spent some time trying to wrap my head around reading in large csv
files with the ff-package. I think I know how to do it, but am bumping
into some problems. I've tried to recreate the issues as best as I can
with a smaller example and maybe someone can help explain the problems.
The following code just creates a csv file with an integer column,
character column and logical column.
2012 Oct 01
3
ffbase, help with %in%
Hello to everyone.
I'm trying to use the %in% to match to vectors in ff format.
a<-as.ff(data[,1]) %in% fire$fecha
> aff (open) logical length=3653 (3653)
[1] [2] [3] [4] [5] [6] [7] [8] [3646]
FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE : FALSE
[3647] [3648] [3649] [3650] [3651] [3652] [3653]
FALSE FALSE FALSE FALSE FALSE FALSE
2011 May 04
1
Problems saving ff objects
Dear list,
I am trying to understand and use the ff package. As I had some problems saving some ff objects, and as I did not fully manage to understand the whole concept of *.ff, *.ffData and *.RData with the help of the documentation, I tried to reproduce the examples from the help of ffsave.
When I ran, however : (copied from the help)
message("let's create some ff objects")
2010 Apr 13
2
how to work with big matrices and the ff-package?
Hello everyone,
I need to create and work with some big matrices that actually have somewhat over 2 million columns and 117 rows. To do some calculations on such big matrices R just needs too much memory for my PC (4GB installed). So I need a solution to work with large datasets. I'm trying to use the ff-package but I don't think I really understand the whole functionality of the
2009 Nov 10
3
Error: cannot allocate vector of size...
I'm trying to import a table into R the file is about 700MB. Here's my first
try:
> DD<-read.table("01uklicsam-20070301.dat",header=TRUE)
Error: cannot allocate vector of size 15.6 Mb
In addition: Warning messages:
1: In scan(file, what, nmax, sep, dec, quote, skip, nlines, na.strings, :
Reached total allocation of 1535Mb: see help(memory.size)
2: In scan(file, what,
2010 Jan 07
1
A question about the ff package
Hi,
I am using version 2.1-1 of the ff package.
I have a data set with 80 million rows and I need to create a new ffdf
object, subseting by values in one of the original ffdf's columns. Here is
my code:
bigData <- read.table.ffdf(file="/data/demodata/data/smallData.txt",
next.rows=1e5, head=TRUE, sep="|")
dim(bigData)
N <- nrow(bigData);N
select <- ff(
2012 Mar 30
3
ff usage for glm
Greetings useRs,
Can anyone provide an example how to use ff to feed a very large data frame to glm?
The data.frame cannot be loaded in R using conventional read.csv as it is too big.
glm(...,data=ff.file) ??
Thank you
Stephen B
2012 May 04
2
Can't import this 4GB DATASET
Dear Experienced R Practitioners,
I have 4GB .txt data called "dataset.txt" and have attempted to use *ff,
bigmemory, filehash and sqldf *packages to import it, but have had no
success. The readLines output of this data is:
readLines("dataset.txt",n=20)
[1] " "
2012 Sep 14
1
Any way to get read.table.ffdf() (in the ff package) to pass colClasses or comment.char parameters through to read.fwf() ?
Hi everyone, my apologies if I'm overlooking something obvious in the
documentation. I'm relatively inexperienced with the (awesome) ff package.
My goal is to use the read.table.ffdf() function to call the read.fwf()
function and pass through the colClasses and comment.char arguments. The
code below shows exactly what doesn't work for me.
If the colClasses and comment.char
2012 Sep 12
1
unzipping with ff
I've noticed that ff uses the unzip utility available on it's host OS to
load datasets via ffload. It seems to work fine in linux, but when I try
to use the package in Windows (hence dling Windows unzip utils) I get 2
errors, one telling me that the options aren't being passed to unzip
correctly and another indicating that my filename is incorrect. First,
does anyone know of an unzip
2001 Nov 01
3
Lost backslashes in parse()
I'm comparing R-1.3.0 on Solaris 2.6 to R-1.3.1 on WindowsNT. The following
5-line script returns TRUE on Unix but FALSE on NT:
fnam <- tempfile()
file.create(fnam)
txt <- paste("file.exists(\"", fnam, "\")", sep="")
expr <- parse(text=txt)
eval(expr)
The issue seems to be that backslashes get lost in the parsing. A workaround
is to change
2010 Feb 12
1
ffsave.image() error with large objects
Hi, I have been using ffsave.image() to save mixture of ff and normal
objects in my workspace. e.g.
ffsave.image(file = "C:\output\saveobjects", rootpath =
"D:\fftempdir", safe = TRUE)
It works fine but once my workspace has large (~4GB) objects, I get the error:
Error in ffsave.image(file = "C:\output\savedobjects", rootpath =
"D:\fftempdir", safe =
2013 Feb 27
0
How to specify ff object filepaths when reading a CSV file into a ff data frame.
Really old subject?, so, all my apologizes for digging up
but, since I also ran into this? maybe this hack can be useful to someone
I propose monkey patching here:
library(ff)
my.as.ffdf.data.frame <- function (x, vmode = NULL, col_args = list(), ...)
{
rnam <- attr(x, "row.names")
if (is.integer(rnam)) {
if (all(rnam == seq_along(rnam)))
rnam <- NULL
else
2012 Sep 26
3
Reading multiple files
Hi,
I have 35 data files for reading. I would like get a program for
performing reading of 35 files at once.
All are of the type: Dados1.raw, Dados2.raw and so on.
If the files have the same number of columns, I can read with the
following commands:
rm(list=ls())
filenames = list.files(path="~/Silvano/Arq", pattern="Dados+.*raw")
names = substr(filenames, 1, 7)
for(i in