Displaying 20 results from an estimated 10000 matches similar to: "how to read just a column"
2006 Aug 31
1
alpha in Holt-Winters method
Hi,
I'd like to know if the Holt-Winters function in R can modify the
alpha paremeter in an "intelligent" way. I know it can vary from 0 to
1.
Wich mathematical formula does it use to calculate the correct value of alpha?
Thanks, bye.
Carlo
2006 Jul 12
4
Is it possible to only read a subset by read.table ?
Hello,
is it possible to do something like
DATA <- read.table(file="blabla.dat",subset=(sex=="male")),
i.e. make R read only a subset of a csv file ?
I think it would be useful in case of very big datasets,
but I can't find such a feature.
Thanks for an answer,
David Vonka
2006 Mar 07
7
reading in only one column from text file
How do I manipulate the read.table function to read in only the 2nd
column???
[[alternative HTML version deleted]]
2011 Nov 08
3
Reading a specific column of a csv file in a loop
Dear all:
I have two larges files with 2000 columns. For each file I am
performing a loop to extract the "i"th element of each file and create
a data frame with both "i"th elements in order to perform further
analysis. I am not extracting all the "i"th elements but only certain
which I am indicating on a vector called "d".
See an example of my code below
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.
2006 Sep 26
2
colClasses: supressed 'NA'
Hi,
The colClasses seem to be supressing 'NA' vlaues. How do I fix this?
R script and first 5 lines of output is below.
File "test2.dat" has blanks that are read as "NA" when I do not use
'colClasses', but as blanks when I use 'colClasses'.
temp.df <- read.fwf("test2.dat", width=c(10,1,1,1,1,2,2,3,3,1),
2009 Dec 24
2
Column naming issues using read.table
Hi, this is my first post so please be gentle.
I quite new to R and using it for my biology degree.
My problem is. Im trying to import data from a .csv file using the
read.table command. The .csv file header starts on row 2 but is contained in
column 1, i have 600 data files and for future ease would rather not edit
each file seperatly. The data starts on row three and I only need the first
381
2005 Feb 03
3
Reading Dates in a csv File
Hi all. I'm reading in a flat, comma-delimited flat file using read.csv.
It works marvelously for the most part. I am using the colClasses argument
to, basically, create numeric, factor and character classes for the columns
I'm reading in. However, a couple of the fields in the file are date
fields. I'm fully aware that POSIXct can be used as a class, however the
field must obey,
2005 Apr 23
2
How to override coerion error in 'scan'
I am using 'read.csv' in V2.0.1 to read in a CSV file with the
colClasses option and am getting an error from 'scan' when it encounters
a non-numeric value for a 'numeric' column, i.e.
> ds <- read.csv(in_file, nrows=irow, row.names=NULL,
colClasses=zclass,
comment.char="")
Error in scan(file = file, what = what, sep = sep, quote =
2004 Dec 26
4
R's IO speed
R-devel now has some improved versions of read.table and write.table.
For a million-row data frame containing one number, one factor with few
levels and one logical column, a 56Mb object.
generating it takes 4.5 secs.
calling summary() on it takes 2.2 secs.
writing it takes 8 secs and an additional 10Mb.
saving it in .rda format takes 4 secs.
reading it naively takes 28 secs and an
2012 Apr 23
1
Can I specify POSIX[cl]t column classes inside read.csv?
I'm loading a nicely formatted csv file.
? ? #!/usr/bin/env Rscript
? ? kpi <- read.csv(
? ? ? # This is a dump of the username, date_joined and last_login columns
? ? ? # from the auth_user Django table.
? ? ? 'data/2012-04-23.csv',
? ? ? colClasses = c('character')
? ? )
? ? print(kpi[sample(nrow(kpi), 3),2:3])
Here's what the three rows I printed look like.
? ? ? ?
2007 Jan 17
3
Row limit for read.table
I have been trying to read in a large data set using read.table, but
I've only been able to grab the first 50,871 rows of the total 122,269 rows.
> f <-
read.table("http://www.cs.odu.edu/~fmccown/R/Tchange_rates_crawled.dat",
header=TRUE, nrows=123000, comment.char="", sep="\t")
> length(f$change_rate)
[1] 50871
From searching the email archives,
2013 Sep 30
4
read.table() with quoted integers
Hi!
It seems that read.table() in R 3.0.1 (Linux 64-bit) does not consider
quoted integers as an acceptable value for columns for which
colClasses="integer". But when colClasses is omitted, these columns are
read as integer anyway.
For example, let's consider a file named file.dat, containing:
"1"
"2"
> read.table("file.dat",
2010 Jul 02
2
unable to get bigglm working, ATTN: Thomas Lumley
I am using an example posted in this help forum to work with a file. the head
of the file looks like:
988887 2007-03-05 2007-06-01 90 3 5.450 205500.00 999.00 999.000 0.000 0 0
988887 2007-03-06 2007-06-01 90 3 5.450 205500.00 999.00 999.000 0.000 1 0
988887 2007-03-07 2007-06-01 90 3 5.450 205500.00 999.00 999.000 -0.100 2 0
988887 2007-03-08 2007-06-01 90 3 5.450 205500.00 999.00 999.000 -0.100
2016 Sep 26
3
Concatenación de tablas
Buenas Tardes,
Les escribo para solicitarles una ayuda dado que tengo 2 tablas, una con los campos:
cedula | nombre | direccion
y la otra con la tabla:
cedula | barrio | municipio
Lo que necesito es hacer una comparación del campo cedula de las dos tablas y si son iguales, agregarle los campos barrio y municipio de la segunda tabla a la fila correspondiente de esa cedula de la primera
2007 Jan 11
1
Treatment for Unequal Column Lengths?
Fellow R Users:
I have a .csv dataset that I have brought into R via read.table (and also
via read.csv). The dataset has columns that are not equal in length.
Essentially, this data file has vectors/columns in which I plan to use
different analyses on, hence they are unequal in length. Also, the columns
are either numeric or calendar dates. Is there a way to prevent R from
appending
2011 Jun 03
4
Problem using read.xls - Everything converted to factors
Hallo,
I would like to use to read.xls function from the gdata package to read
data from Microsoft Excel files but I experienced a problem: For example
I used the following code:
testfile<-read.xls("/home/.../wsjecon0603.xls", #file path
header=F,
dec=",",
na.strings="n.a.",
skip=5,
sheet=2,
2011 Dec 08
2
read.table question
Hello All,
This works,
results <- read.table("plink.txt",T)
while this doesn't.
results <- read.table("plink.txt")
Make sure your data frame contains columns CHR, BP, and P
What does adding the "T" in read.table do? Which argument does this
correspond to? I tried searching for it but didn't find the answer in:
read.table(file, header = FALSE,
2010 Oct 13
1
RODBC: forcing a special column to be read in as character
Dear R-users,
I am working with R version 2.10.1 and package RODBC Version: 1.3-2 under windows.
Say I have a table "testtable" (in an Access data base), which has many different columns, among them a character column "X" with "integer-like" data as "0012345".
Using sqlFetch, I'd like to assure that column X is read in as a character variable. So what