Displaying 20 results from an estimated 9000 matches similar to: "using names with functions.."
2006 Nov 03
1
difference in using with() and the "data" argument in glm call
Dear all,
I am dealing with the following (apparently simple problem):
For some reasons I am interested in passing variables from a dataframe
to a specific environment, and in fitting a standard glm:
dati<-data.frame(y=rnorm(10),x1=runif(10),x2=runif(10))
KK<-new.env()
for(i in 1:ncol(dati)) assign(names(dati[i]),dati[[i]],envir=KK)
#Now the following two lines work correctly:
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
--
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)
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
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
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
2008 Jan 16
1
strange behaviour of is.factor()
Dear all,
It appears that the function is.factor() returns different results when
used inside the apply() function: that is, is.factor() fails to
recognize a factor..
Where is the trick?
many thanks,
vito
> df1<-data.frame(y=1:10,x=rnorm(10),g=factor(c(rep("A",6),rep("B",4))))
> is.factor(df1[,1])
[1] FALSE
> is.factor(df1[,2])
[1] FALSE
>
2006 Mar 01
1
a strange problem with integrate()
Dear all,
I am stuck on the following problem with integrate(). I have been out of
luck using RSiteSearch()..
My function is
g2<-function(b,theta,xi,yi,sigma2){
xi<-cbind(1,xi)
eta<-drop(xi%*%theta)
num<-exp((eta + rep(b,length(eta)))*yi)
den<- 1 + exp(eta + rep(b,length(eta)))
result=(num/den)*exp((-b^2)/sigma2)/sqrt(2*pi*sigma2)
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,
2007 Jul 11
3
3D plot and interactive PDFs
With version 8 of acrobat reader, it is now possible to have 3D in PDf documents.
Does it exist already an R package who manage to produce 3D plots which can be saved as interactive 3D graphs in a PDF file?
Best Regards
Bruno Cavestro
------------------------------------------------------
Leggi GRATIS le tue mail con il telefonino i-mode? di Wind
http://i-mode.wind.it/
2007 Apr 03
3
Testing additive nonparametric model
I have estimated a multiple nonparametric regression using the loess
command in R. I have also estimated an additive version of the model using
the gam function. Is there a way of using the output of these two models to
test the restrictions imposed by the additive model?
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
2012 Jun 01
1
getting the name of the working .Rdata file
dear all,
I do not if it is a nonsense question..
Is it possible in the R session to get the name of the current .Rdata
file that I ran?
I mean: suppose I double click the file myfile.Rdata. ls() returns the
names of the objects in the current workspace (that is saved in
myfile.Rdata). In the current R session, I would like to obtain
"myfile.Rdata". Is it possible?
Thanks in
2012 Mar 21
1
glmnet() vs. lars()
dear all,
It appears that glmnet(), when "selecting" the covariates entering the
model, skips from K covariates, say, to K+2 or K+3. Thus 2 or 3
variables are "added" at the same time and it is not possible to obtain
a ranking of the covariates according to their importance in the model.
On the other hand lars() "adds" the covariates one at a time.
My question
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
2
Segmented regression
Hello all,
I have 3 time series (tt) that I've fitted segmented regression models
to, with 3 breakpoints that are common to all, using code below
(requires segmented package). However I wish to specifiy a zero
coefficient, a priori, for the last segment of the KW series (green)
only. Is this possible to do with segmented? If not, could someone point
in a direction?
The final goal is to
2006 Jan 18
1
Breakpoints for multiple variables using Segmented
Hi all,
I am using the package ?Segmented? to estimate logistic regression models
with unknown breakpoints (see Muggeo 2003 Statistics in Medicine
22:3055-3071). In the documentation it suggests that it might be possible to
include several variables with breakpoints in the same model: ?Z = a vector
or a matrix meaning the (continuous) explanatory variable(s) having
segmented relationships with
2024 Jul 26
1
Automatic Knot selection in Piecewise linear splines
dear all,
I apologize for my delay in replying you. Here my contribution, maybe
just for completeness:
Similar to "earth", "segmented" also fits piecewise linear relationships
with the number of breakpoints being selected by the AIC or BIC
(recommended).
#code (example and code from Martin Maechler previous email)
library(segmented)
o<-selgmented(y, ~x, Kmax=20,
2006 Oct 17
2
Question about managing searching path
Hi all,
I'm having sometrouble with managing the seach path, in a function , I need to attach some data set at the begining
and detach them at the end, say, myfunction<- function() { attach(mylist); ............. detach(mylist) } ,
the problem is, since I am still debugging this code, sometimes it got error and ended before reaching the end, thus
the data is left in the