Displaying 20 results from an estimated 20000 matches similar to: "someProblem in R-1.4.1"
2009 Nov 02
3
partial matching with grep()
dear all,
This is a probably a silly question.
If I type
> grep("x",c("a.x" ,"b.x","a.xx"),value=TRUE)
[1] "a.x" "b.x" "a.xx"
Instead, I would like to obtain only
"a.x" "b.x"
How is it possible to get this result with grep()?
many thanks for your attention,
best,
vito
--
2013 Jan 11
1
problems with package 'segmented'
Dear R-users,
I am trying to understand how the 'segmented'-package works to determine
breakpoints and slopes of regression lines in broken-line regression models.
However, I am not able to repeat the example on the "plant"-dataset,
which was reported in the accompanying paper of the package. (V.M.R
Muggeo, "Segmented: an R package to fit regression models with
2003 Apr 17
4
A function as argument of another function
Dear all,
I would like to write a function like:
myfun<-function(x,fn) {xx<-exp(x); x*fn(xx)}
where fn is a symbolic description of any function with its argument to be
specified. Therefore
myfun(5,"2+0.3*y^2")
should return 5*(2+0.3*exp(5)^2),
myfun(5,"log(y)") should return 5*log(exp(5)) and so on.
I tried with "expression" and others, but without success.
2012 Mar 12
1
Fwd: Re[2]: B-spline/smooth.basis derivative matrices
--- On Mon, 3/12/12, aleksandr shfets <a_shfets at mail.ru> wrote:
> From: aleksandr shfets <a_shfets at mail.ru>
> Subject: Fwd: Re[2]: [R] B-spline/smooth.basis derivative matrices
> To: "Vassily Shvets" <shv736 at yahoo.com>
> Received: Monday, March 12, 2012, 5:15 PM
>
>
>
> -------- ???????????? ?????????
> --------
> ?? ????:
2008 Jun 30
2
difference between MASS::polr() and Design::lrm()
Dear all,
It appears that MASS::polr() and Design::lrm() return the same point
estimates but different st.errs when fitting proportional odds models,
grade<-c(4,4,2,4,3,2,3,1,3,3,2,2,3,3,2,4,2,4,5,2,1,4,1,2,5,3,4,2,2,1)
score<-c(525,533,545,582,581,576,572,609,559,543,576,525,574,582,574,471,595,
557,557,584,599,517,649,584,463,591,488,563,553,549)
library(MASS)
library(Design)
2018 Jan 30
2
variable names in lm formula ~.
dear all,
Is the following intentional? Am I missing anything in documentation?
d<-data.frame(y=rnorm(10,5,.5),exp=rnorm(10), age=rnorm(10))
formula(lm(exp(y)~exp+age, data=d))
#--> exp(y) ~ exp + age
formula(lm(exp(y)~., data=d))
#--> exp(y) ~ age
variable 'exp' (maybe indicating "experience") is not included in the
model. The same happens with 'log' (and
2003 Dec 16
3
`bivariate apply'
dear all,
Given a matrix A, say, I would like to apply a bivariate function to each
combination of its colums. That is if
myfun<-function(x,y)cor(x,y) #computes simple correlation of two vectors x
and y
then the results should be something similar to cor(A).
I tried with mapply, outer,...but without success
Can anybody help me?
many thanks in advance,
vito
2007 Nov 28
3
using names with functions..
Dear all,
I have the following (rather) strange problem..
For some reasons, I finally work with a variable whose name includes an
R function, "a.log(z)", say. And that is a problem when I call it in a
formula, for instance:
> myname<-"a.log(z)"
> dd<-data.frame("a.log(z)"=1:10,y=rnorm(10))
> o<-lm(y~1,data=dd)
>
2010 Mar 04
1
only actual variable names in all.names()
dear all,
When I use all.vars(), I am interest in extracting only the variable names..
Here a simple example
all.vars(as.formula(y~poly(x,k)+z))
returns
[1] "y" "x" "k" "z"
and I would like to obtain
"y" "x" "z"
Where is the trick?
many thanks
vito
--
====================================
Vito M.R. Muggeo
Dip.to Sc
2006 Feb 27
3
how to use the basis matrix of "ns" in R? really confused by multi-dim spline filtering?
Hi all,
Could anybody recommend some easy-to-understand and example based
notes/tutorials on how to use cubic splines to do filtering on
multi-dimension data?
I am confused by the 1-dimensional case, and more confused by
multi-dimensional case.
I found all the books suddenly become very abstract when it comes to this
subject.
They don't provide examples in R or Splus at all.
Specifically,
2004 Oct 26
2
vcov method for 'coxph' objects
Dear all,
The help file for the generic function vcov states
"Classes with methods for this function include: 'lm', 'glm', 'nls', 'lme',
'gls', 'coxph' and 'survreg' (the last two in package 'survival')."
Since, I am not able to use vcov.coxph(), I am wondering whether I am
missing something (as I suspect..)
regards,
vito
2008 Jun 10
2
Slow function
Hi,
I have the following function that I want to apply to a list of 14
matrices (1536 x 170) of binary data:
DRes <- function(x, nr = 10000, metric = "mixed", ...) {
require(analogue)
require(ade4)
m <- c()
for (i in 1:nr) {
set.seed(i)
x1 <- x[, sample(dimnames(x)[[2]], length(x[1,])/2)]
x2 <- x[, !dimnames(x)[[2]] %in% dimnames(x1)[[2]]]
d1 <-
2018 Jan 30
0
variable names in lm formula ~.
Functions are first class objects, so some kind of collision is bound to happen if you do this... so don't.
--
Sent from my phone. Please excuse my brevity.
On January 30, 2018 3:11:56 AM PST, "Vito M. R. Muggeo" <vito.muggeo at unipa.it> wrote:
>dear all,
>Is the following intentional? Am I missing anything in documentation?
>
2018 May 21
2
removing part of a string
dear all,
I am stuck on the following problem. Give a string like
ss1<- "z:f(5, a=3, b=4, c='1:4', d=2)"
or
ss2<- "f(5, a=3, b=4, c=\"1:4\", d=2)*z"
I would like to remove all entries within parentheses.. Namely, I aim to
obtain respectively
"z:f()" or "f()*z"
I played with sub() and gsub() but without success..
Thank you very
2007 Dec 06
1
differences in using source() or console
Dear all,
Is there *any* reason explaining what I describe below?
I have the following line
myfun(x)
If I type them directly in R (or copy/past), it works..
However if I type in R 2.6.1
> source("code.R") ##code.R includes the above line
Error in inherits(x, "data.frame") : object "d" not found
namely myfun() does not work correctly.
In particular the
2008 May 02
1
error in using by + median
dear all,
Could anyone explain me the behaviour of median() within by()?
(I am running R.2.7.0)
thanks,
vito
> H<-cbind(rep(0:1,l=20),matrix(rnorm(20*2),20,2))
> by(H[,-1],H[,1],mean)
INDICES: 0
V1 V2
-0.2101069 0.2954377
---------------------------------------------------------------------------------------------------------------------
INDICES: 1
V1
2019 Sep 11
2
'==' operator: inconsistency in data.frame(...) == NULL
Sorry, I can't reproduce the example below even on the same machine.
However, the following example produces the same error as NULL values in
prior examples:
> setClass("FOOCLASS",
+????????? representation("list")
+ )
> ma = new("FOOCLASS", list(M=matrix(rnorm(300), 30,10)))
> isS4(ma)
[1] TRUE
> data.frame(a=1:3) == ma
Error in
2012 Feb 24
1
B-spline/smooth.basis derivative matrices
Hello,
I've noticed that SPLUS seems to have a function for evaluating derivative matrices of splines. I've found the R function that evaluates matrices from 'smooth.spline'; maybe someone has written something to do the same with smooth.basis?
regards,
s
2010 Oct 25
1
building lme call via call()
dear all,
I would like to get the lme call without fitting the relevant model.
library(nlme)
data(Orthodont)
fm1 <- lme(distance ~ age, random=list(Subject=~age),data = Orthodont)
To get fm1$call without fitting the model I use call():
my.cc<-call("lme.formula", fixed= distance ~ age, random = list(Subject
= ~age))
However the two calls are not the same (apart from the data
2002 Oct 28
4
arima() in for loop
hi all,
In a simulation context I'm running in a for loop the arima() function
for( i in 1:1000){
y<-arima.sim(....)
out<-arima(y,....)
........
}
Everything works, but after some cycle (10, say) I get error due to the
particular y-values simulated. (E.g., a *frequent* error is "Error in
svd(na.omit(xreg)) : 0 extent dimensions") As a