Displaying 20 results from an estimated 3000 matches similar to: "ifelse on data frames"
2010 Jul 27
4
Sweave and scan()
I am introducing the scan() function to my class. Consider the following
file (Scanexamp.Rnw )
\documentclass[12pt]{article}
\begin{document}
<<>>=
height = scan()
64 62 66 65 62
69 72 72 70
part = scan(what = character(0))
"Soprano" "Soprano" "Soprano"
"Alto" "Alto" "Tenor"
"Tenor" "Bass"
2006 Apr 14
5
vector-factor operation
I found myself wanting to average a vector [vec] within each level of a
factor [Fac], returning a vector of the same length as vec. After a
while I realised that
lm1 <- lm(vec ~ Fac)
fitted(lm1)
did what I want.
But there must be another way to do this, and it would be good to be
able to apply other functions than mean() in this way.
Cheers, Murray
--
Dr Murray Jorgensen
2003 Sep 17
5
Quit asking me if I want to save the workspace!
How do you stop R from putting up a dialog box when you quit Rgui?
(I use Windows and I never save workspaces that way)
Murray
--
Dr Murray Jorgensen http://www.stats.waikato.ac.nz/Staff/maj.html
Department of Statistics, University of Waikato, Hamilton, New Zealand
Email: maj at waikato.ac.nz Fax 7 838 4155
Phone +64 7 838 4773 wk +64 7 849 6486 home
2001 May 22
2
MASS data sets
I'm running R 1.2.2 under windows 98 on a Pentium 133 laptop.
I can't seem to retrieve the package MASS data sets:
> library(MASS)
> data(wtloss)
Warning message:
Data set `wtloss' not found in: data(wtloss)
> data(abbey)
Warning message:
Data set `abbey' not found in: data(abbey)
And yet all the .rda files for the MASS datasets are in
D:\Program
2011 Jan 05
4
Converting Fortran or C++ etc to R
I'm going to try my hand at converting some Fortran programs to R. Does
anyone know of any good articles giving hints at such tasks? I will post
a selective summary of my gleanings.
Cheers, Murray
--
Dr Murray Jorgensen http://www.stats.waikato.ac.nz/Staff/maj.html
Department of Statistics, University of Waikato, Hamilton, New Zealand
Email: maj at waikato.ac.nz
2003 Aug 20
5
Interlacing two vectors
I want to interlace two vectors. This I can do:
> x <- 1:4
> z <- x+0.5
> as.vector(t(cbind(x,z)))
[1] 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
but this seems rather inelegant. Any suggestions?
Murray
--
Dr Murray Jorgensen http://www.stats.waikato.ac.nz/Staff/maj.html
Department of Statistics, University of Waikato, Hamilton, New Zealand
Email: maj at waikato.ac.nz
2003 Dec 30
4
Assignments in loops
Greetings all. Any help with the following would be appreciated.
I want to create a data frame for each file in a directory. The following
code does not work but it may show what I am trying to do:
carmakes <- c('BMW','Chrysler','Citroen','Fiat','Ford','Holden','Honda',
2003 Sep 23
2
R-project [.com?] [.net?]
I got a shock a few days ago when I accidentally visited
www.r-project.com . I thought that the r-project site had been hacked
until I realised my mistake. There is also a site www.r-project.net.
Both of these sites appear to be Japanese. Does anyone know anything
about them? I suppose that it is not unusual for names close to those of
popular sites to be used. It is good that they use a
2001 Nov 12
3
Plotting symbols
Has anyone got a cute way of compiling a table of the available plotting
symbols?
I've been repeatedly pasting in
cno <- cno + 1
cno
plot(x,y,pch=cno)
which is tedious, and besides I have to note down the symbols by hand.
Dr Murray Jorgensen http://www.stats.waikato.ac.nz/Staff/maj.html
Department of Statistics, University of Waikato, Hamilton, New Zealand
Email: maj at
2004 Apr 21
2
Rgui front-end has encountered a problem and needs to close
Well I don't know if anyone can help with this but it will be
interesting to know if others have had the same problem.
I can't start R at home on my laptop [ I'm using 1.8.1 under Windows
XP]. When I click on the shortcut I get the usual Windows box for when
an application needs to close. A couple of clicks down it displays the
following:
Error signature
AppName: rgui.exe
2006 Nov 13
2
A printing "macro"
I am exploring the result of clustering a large multivariate data set
into a number of groups, represented, say, by a factor G.
I wrote a function to see how categorical variables vary between groups:
> ddisp <- function(dvar) {
+ csqt <- chisq.test(G,dvar)
+ print(csqt$statistic)
+ print(csqt$observed)
+ print(round(csqt$expected))
+ round(csqt$residuals)
+ }
>
> x
2001 Oct 02
3
Accessing just the value of an object but not the attributes
I have the feeling that this is a dumb question but oh well ...
When I have an object x with several attributes,
y <- x will make a copy of x with all the attributes included.
What if I just want y to get the value assigned but nothing
else (no class, names, dim or other attributes)?
Johann
--
Phone/FAX/Adr/PGPkey ... at http://www.ai.univie.ac.at/~johann
2004 Jul 07
6
text editor for R
Hi,
What is the best text editor for programming in R? I am using JEdit as the
text editor, however, it does not have anything specific for R. It will be
nice to have a developing environment where the keywords are highlighted,
plus some other debugging functions.
Yi-Xiong
[[alternative HTML version deleted]]
2008 Mar 02
2
Recommended Packages
Having just update to R 2.6.2 on my old Windows laptop I notice that the
number of packages is growing exponentially and my usual approach of
get-em-all may not be viable much longer. Has any thought been given to
dividing "contributed" binaries into a recommended set, perhaps a couple
of hundred, and the remained. That way one could install the recommended
ones routinely and add in
2006 Aug 01
4
Fitting models in a loop
If I want to display a few polynomial regression fits I can do something
like
for (i in 1:6) {
mod <- lm(y ~ poly(x,i))
print(summary(mod))
}
Suppose that I don't want to over-write the fitted model objects,
though. How do I create a list of blank fitted model objects for later
use in a loop?
Murray Jorgensen
--
Dr Murray Jorgensen
2003 Dec 08
2
Character graphics
Does anyone else miss email-friendly character graphics such as the
following example, produced using Minitab?
Histogram of C6 N = 478 N* = 21
Each * represents 2 observation(s)
Midpoint Count
-12 16 ********
-11 53 ***************************
-10 63 ********************************
-9 83
2004 Apr 24
5
Modalwert
Hai -
kann mir jemand sagen, wie ich den Modalwert in R berechne?! IRgendwie finde
ich den Befehl nicht....
greetz und herzlichen Dank
Sonja
2006 Aug 20
3
unquoting
I would like a function to strip quotes off character strings. I should
work like this:
> A <- matrix(1:6, nrow = 2, ncol=3)
> AF <- as.data.frame(A)
> names(AF) <- c("First","Second","Third")
> AF
First Second Third
1 1 3 5
2 2 4 6
> names(AF)[2]
[1] "Second"
> attach(AF)
>
2007 Dec 05
2
Dimension of a vector
Consider the following:
> A <- 1:10
> A
[1] 1 2 3 4 5 6 7 8 9 10
> dim(A)
NULL
> dim(A) <- c(2,5)
> A
[,1] [,2] [,3] [,4] [,5]
[1,] 1 3 5 7 9
[2,] 2 4 6 8 10
> dim(A)
[1] 2 5
> dim(A) <- 10
> A
[1] 1 2 3 4 5 6 7 8 9 10
> dim(A)
[1] 10
Would it not make sense to have dim(A) = length(A) for all vectors?
2002 Dec 03
2
Array multiplication
I wanted a sort of matrix product of an array and a matrix.
As there does not seem to be any array multiplication apart from outer()
I proceeded as follows:
lambda <- array(0, c(n,m,d))
# stuff omitted
# zed is an n by m matrix
#
# \lamb.star_{ik}
lamb.star <- matrix(0, nrow=n, ncol=d)
for (i in 1:n) {
for (k in 1:d) {
for (j in 1:m) {
lamb.star[i,k] = lamb.star[i,k] +