Displaying 20 results from an estimated 7000 matches similar to: "No reorder.factor in R"
2002 Nov 21
4
Mixing text and graphics in PDF
Is there an easy way to "sink" text output to a pdf file using the pdf()
device?
Here's an email that describes setting up empty graphics plots and then
using the "text" command to put text on page:
http://www.r-project.org/nocvs/mail/r-help/2002/5598.html
I'm just looking for something a little more polished -- automatic page
breaks, line wrapping, etc.
Kevin
2002 Oct 01
0
Possible inconsistency with mean & var
I encountered an unexpected difference in the way that mean and var work:
> mean(numeric(0))
[1] NaN
> var(numeric(0))
Error in var(numeric(0)) : `x' is empty
Looking into this, I discovered in mean.default that sum(x)/n
evaluates as
> sum(numeric(0))/length(numeric(0))
[1] NaN
The function var calls an .Internal and seems to evaluate this:
>
2003 Jan 10
1
Suggested modification to shell command
I'm using R 1.6.1 on Windows 95 with cygwin bash as my shell.
The 'shell' command tries to determine which shell the user prefers via the
following steps:
shell <- Sys.getenv("R_SHELL")
if (!nchar(shell))
shell <- Sys.getenv("SHELL")
if (!nchar(shell))
shell <- Sys.getenv("COMSPEC")
For me, shell
2006 Sep 29
2
GLM information matrix
Is there a function that provides the Fisher information matrix for a
generalized linear model? I do not see how to access the off-diagonal
matrix elements of the value returned by glm. (I'm particularly
interested in logistic regression.)
If not, what is a good way to use R to compute Hessians or other partial
derivatives of log likelihoods?
I would appreciate any guidance.
David
2001 Dec 27
5
new lattice/grid
I just installed R-1.4.0 on my Win2k machine from SetupR.exe. Everything
seems to be fine with the base and recommended packages. However, when I
install the lattice and grid packages they do not seem to work. Everything
I try results in something like this:
Instruction 0x00543f06 refernced memory 0x00000000. The memory cannot
be "read".
and I am getting kicked out of R.
Has
2004 Sep 03
2
debugging an S4 method
Does anyone know how to use the equivalent of debug() on an S4 method? I would like R to enter the browser not for the generic function, but for the method of the class that I specify.
Thanks,
David
_____________________________
David Bickel http://davidbickel.com
Research Scientist
Pioneer Hi-Bred International
Bioinformatics & Exploratory Research
7250 NW 62nd Ave., PO Box 552
Johnston,
2005 Feb 22
2
estimate the parameter of exponential distribution, etc.
Given a numeric vector of observations, does R have any generic way to estimate the parameters of commonly used distributions (exponential, gamma, etc.) without numerically optimizing the likelihood function?
Thanks,
David
_______________________________________
David R. Bickel http://davidbickel.com
Research Scientist
Pioneer Hi-Bred International
Bioinformatics & Exploratory Research
7250
2004 Aug 31
2
enter browser on error
Is there a way I can get R to automatically enter the browser inside a user-defined function on the generation of an error? Specifically, I'm trying to debug this:
Error in as.double.default(sapply(lis, FUN)) :
(list) object cannot be coerced to double
In addition: There were 38 warnings (use warnings() to see them)
> traceback()
8: as.double.default(sapply(lis, FUN))
7:
2005 Dec 23
2
convolution of the double exponential distribution
Is there any R function that computes the convolution of the double
exponential distribution?
If not, is there a good way to integrate ((q+x)^n)*exp(-2x) over x from
0 to Inf for any value of q and for any positive integer n? I need to
perform the integration within a function with q and n as arguments. The
function integrate() is giving me this message:
"evaluation of function gave a
2008 Sep 04
1
text file imported incorrectly
Dear R-users,
When I tried to import a text file (tab delimited) which has 2000+ rows with the following command (With the importData in S, it works though),
x <- read.table(textfile, sep= "\t", skip=5, stringAsFactors=F)
I received the following warning message: Error in scan(file, what, nmax, sep, dec, quote, skip, nlines, na.strings,: number of items read is not a multiple of
2004 Aug 02
2
random seed puzzle
After reading the help page on set.seed, I am unsure about how to solve the following problem. I need to call function f a thousand times. The list of values returned by f, should be as random as possible. f calls g twice:
f <- function(){g1 <- g(1); g2 <- g(2); c(g1; g2)}
The function g in turn calls sample and returns a number, but also depends on its argument, so, starting from the
2013 Dec 14
2
Change factor levels
Suppose I have a dataframe 'd' defined as
L3 <- LETTERS[1:3]
d0 <- data.frame(cbind(x = 1, y = 1:10), fac = sample(L3, 10, replace
= TRUE))
(d <- d0[d0$fac %in% c('A', 'B'),])
x y fac
2 1 2 B
3 1 3 A
4 1 4 A
5 1 5 A
6 1 6 B
8 1 8 A
Even though factor 'fac' in 'd' only has 2 levels, but it seems to bear the
birthmark
2009 May 22
1
regrouping factor levels
Hi all,
I had some trouble in?regrouping factor levels for a variable. After some experiments, I have figured out how I can recode to modify the factor levels. I would now like some help to understand why some methods work and others don't.
Here's my code :
rm(list=ls())
###some trials in recoding factor levels
char<-letters[1:10]
fac<-factor(char)
levels(fac)
print(fac)
##first
2006 Nov 17
1
Problems in "plot.lm" with option "which=5"
Hi:
I think I found an error in plot.lm with the option which=5, of course I can be wrong , as usually happen, but I had work on it for a while and show it to some other people that work with R, and so far I don't see what I can be interpreting wrong. I also worked over the plot.lm's code and change some lines to get what I call "the right plot", if any body is
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
2005 Mar 31
1
Contingency table: logistic regression
Hi,
I am analyzing a data set with greater than 1000 independent cases
(collected in an unrestricted manner), where each case has 3 variables
associated with it: one, a factor variable with 0/1 levels (called XX),
another factor variable with 8 levels (X) and a third response variable
with two levels (Y: 0/1). I am trying to see if X1 has an effect on the
relationship between X2 and the
2009 Nov 05
2
[LLVMdev] Strange error for libLLVMCore.a
mingw, llvm 2.6 (buid with llvm-gcc)
Example source code:
http://npcontemplation.blogspot.com/2008/06/secret-of-llvm-c-bindings.html
I change
LLVMCreateJITCompiler(&engine, provider, &error);
to
LLVMCreateJITCompiler(&engine, provider, 3, &error);
$ llvm-gcc `llvm-config --cflags` -c fac.c
$ g++ `llvm-config --libs --cflags --ldflags core analysis
executionengine jit
2006 Jan 23
1
Sample rows in data frame by subsets
Hi,
I need to resample rows in a data frame by subsets
L3 <- LETTERS[1:3]
d <- data.frame(cbind(x=1, y=1:10), fac=sample(L3, 10, repl=TRUE))
x y fac
1 1 1 A
2 1 2 A
3 1 3 A
4 1 4 A
5 1 5 C
6 1 6 C
7 1 7 B
8 1 8 A
9 1 9 C
10 1 10 A
I have seen this used to sample rows with replacement
d[sample(nrow(d), replace=T), ]
x y fac
7 1 7 B
2
2009 Jun 03
1
Need help understanding output from aov and from anova
Hi all,
I noticed something strange when I ran aov and anova.
vtot=c(7.29917, 7.29917, 7.29917) #identical values
fac=as.factor(c(1,1,2)) #group 1 has first two elements, group 2 has
the 3rd element
When I run:
> anova(lm(vtot~fac))
Analysis of Variance Table
Response: vtot
Df Sum Sq Mean Sq F value Pr(>F)
fac 1 1.6818e-30 1.6818e-30 0.3333 0.6667
Residuals 1
2012 May 29
1
GAM interactions, by example
Dear all,
I'm using the mgcv library by Simon Wood to fit gam models with interactions and I have been reading (and running) the "factor 'by' variable example" given on the gam.models help page (see below, output from the two first models b, and b1).
The example explains that both b and b1 fits are similar: "note that the preceding fit (here b) is the same as