Displaying 20 results from an estimated 5000 matches similar to: "Adding Histograms to Leaves of Rpart Tree or other Dendrogram"
2006 Dec 04
2
Library file for the R engine in Windows?
Hi,
I am trying to use dynamic memory allocation in the C code to be called by R
through the .C interface.
I have used R_alloc as explained in the Writing R Extensions and included
the R.h header.
The program compiles fine but fails when linking. Obviously it needs a
library file where R_alloc is found.
I have tried to link by adding R.dll to list of files at the end of the link
command but
2007 Dec 11
5
book on regular expressions
Hello,
Could someone recommend a good book on regular expressions with focus on
applications/use as it might relate to R. I remember there was a mention of
such a reference book recently, but I could not locate that message on the
archive.
Thanks.
-Christos
Christos Hatzis, Ph.D.
Nuvera Biosciences, Inc.
400 West Cummings Park
Suite 5350
Woburn, MA 01801
Tel: 781-938-3830
2006 Dec 24
2
how to 'get' an object that is part of a list
This might be an trivial thing but I am stuck.
Consider:
xx <- list(a=1:5, b=letters[1:5])
Although object xx is accessible through its name,
how can object xx$b be accessed similarly through its name?
> get("xx")
$a
[1] 1 2 3 4 5
$b
[1] "a" "b" "c" "d" "e"
> get("xx$b")
Error in get(x, envir, mode, inherits)
2007 Feb 07
2
blank upper or lower triangle of cor-matrix
Dear altogether,
I want to blank the lower (or upper) part of a correlation matrix as it
is done by dist()
example:
( d <- cor(matrix(runif(12),nrow=4)) )
If I do the following
d[lower.tri(d)] <- ""
of course everything is changed to character - that's not what should be.
Additionally, it does not work to assign "0" or anything else. The same
is true for
2007 Feb 01
3
Lining up x-y datasets based on values of x
Hi,
I was wondering if there is a direct approach for lining up 2-column
matrices according to the values of the first column. An example and a
brute-force approach is given below:
x <- cbind(1:10, runif(10))
y <- cbind(5:14, runif(10))
z <- cbind((-4):5, runif(10))
xx <- seq( min(c(x[,1],y[,1],z[,1])), max(c(x[,1],y[,1],z[,1])), 1)
w <- cbind(xx, matrix(rep(0, 3*length(xx)),
2006 Nov 20
2
predict.coxph
Hi everyone,
Can anyone give me more details about the 'lp', 'risk', 'terms', and 'expected'
options from the predict.coxph function?
I actually found that risk is obtained from exp(lp). I can't find information on
'expected' type however. Is anybody can expand the information on this function?
Thank you in advance, I will appreciate it.
2007 May 16
2
'attach workspace' on R console File menu
Quite often I save misc functions and data objects as .RData files that I
can use in other sessions. Although I could 'Load Workspace" these files,
most of the times I prefer attaching them. It would be really convenient to
have a menu item under the File menu on the Windows R Console to allow
attaching workspaces, e.g.
--------------------
Attach Workspace...
Load Workspace...
Save
2006 Oct 24
2
Plotmath expression
Hello,
I've been trying to plot a subscript in a text formula using plotmath but I
haven't been able to do so.
In my example below I would like the text label to show
X[min] = 10.1 +/- 5.5
Here is the code:
ll <- c(x=10.1, sde=5.5)
plot(1:10)
text(x=9, y=2, pos=2, expression(paste(X[min], "=", paste(ll,
collapse="+/-"))))
This works fine up to the inner paste
2006 Dec 03
1
passing matrix as argument to a C function
Hi,
Although this is not directly an R-related question, it is relevant as I am
trying to port some R code to C to speed things up in a computation.
I am working through my first attempts to generate and link compiled C code
in R. I could make the 'convolve' function to work and similar functions
that take vectors as arguments. In my application I need to pass a couple
of matrices to
2009 Sep 10
1
importing/loading package without a namespace
I am developing a package that imports some functions from another package.
The imported package (qcc) does not have a namespace and this is causing
problems with loading of my package, which has a namespace. Is there a
workaround to allow loading the namespace-less package?
I searched the archives and found a suggestion that the package should be
included in the Depends list, but this has not
2007 Apr 26
2
Extract p-value from survdiff function
Hi list,
I want to use the p-value from the survdiff function (package
survival) to reuse within a function in a Kaplan-Meier plot. The
p-value is somehow not a component of the value list ?!
Thanks in advance
--
A. Goralczyk
G?ttingen, Ger.
2007 Feb 01
1
Loading functions in R
Hi all,
This information must be out there, but I can't seem to find it. What I
want to do is to store functions I've created (as .R files or in
whatever form) and then load them when I need them (or on startup) so
that I can access without cluttering my program with the function code.
This seems like it should be easy, but....
Thanks!
Jeff
2007 Oct 09
1
Visualize cox proportional hazards
Hello all
I would like to visualize the hazard ratios of a cox proportional
hazards model. I have seen some good examples in the New England
Journal of Medicine:
http://content.nejm.org/cgi/content/short/353/26/2747/F3
http://content.nejm.org/cgi/content/short/350/26/2654/F2
(I hope these are open access, but I am not sure)
And something similar in the book 'R Graphics' by Paul
2006 Jul 18
1
bilinear regression
I think this is an easy question, but I would be grateful for any advice
on how to implement this in R.
I simply have a response variable (y) that I am trying to predict with
one explanatory variable (x) but the shape of the scatter plot is
distinctly bilinear. It would be best described by two straight lines.
Is there a way of fitting a linear model to give me a bilinear fit and
(more
2007 Mar 09
2
Duplicate rows of matrix
Hello my problem is the following:
I have a matrix A and a vector B which contains as many rows as A.
I need to build a matrix C which contains B[i]-times the row A[i,] and this for each line of A.
if for example A is
[1] [2]
[1] 8 9.4
[2] 4.2 1.1
and B is (3,1). Then C will be:
[1] [2]
[1] 8 9.4
[2] 8 9.4
[3] 8 9.4
[4] 4.2 1.1
I have some
2006 Mar 07
1
breslow estimator for cumulative hazard function
Dear R-users,
I am checking the proportional hazard assumption of a cox model for a
given covariate, let say Z1, after adjusting for other relavent covariates
in the model. To this end, I fitted cox model stratified on the discrete
values of Z1 and try to get beslow estimator for the baseline cumulative
hazard function (H(t)) in each stratum. As far as i know, if the
proportionality assumption
2007 Jan 20
4
simple q: returning a logical vector of substring matches
I'm a relative R novice, and sometimes the simple things trip me up.
Suppose I have
a <- c("apple", "pear")
and I want a logical vector of whether each of these strings contains
"ear" (in this case, F T). What is the idiom?
Quizzically,
Mark Lindeman
2007 Mar 03
3
Help with paste()
Dear r-helpers,
Could you please tell me what's missing:
rbind(paste('txt.est',1:24, sep = ''))
txt.est1, ... txt.est24 are vectors that I wish to rbind.
_____________________________
Professor Michael Kubovy
University of Virginia
Department of Psychology
USPS: P.O.Box 400400 Charlottesville, VA 22904-4400
Parcels: Room 102 Gilmer Hall
McCormick Road
2007 May 02
3
the Surv function
Hi,
I'm trying to do a simple survival analysis on some data, and I'm having the
following problem (here's my code and the error message):
out <- Surv(fup,event=status)
Error in Surv(fup, event = status) : argument "time2" is missing, with no
default
>From reading the documentation, it seems that I should be able to simply
write: Surv(time1, event) if my data is
2006 Nov 16
3
X-fold cross validation function for discriminant analysis
Hi all,
I ran a discriminant analysis with some data and want to get a general idea
of prediction error rate. Some have suggested using X-fold cross validation
procedure. Anyone know if there is a function for this in R?
Thanks,
Wade
[[alternative HTML version deleted]]