Hi everyone,
I have a dataset(named "Mydata") which includes 4 different variables
named;
s1,s2,s3,s4 .Each variable(symptom) has 14 patients.
I need to use random sampling to make, 5 different samples from my data with
5 patients in each sample. i.e. using all 4 variables I need to make 5
different samples by changing patients(with 5 patients in each sample).
X8 X9 X10 X102 X110 X177 X283 X284 X286 X292 X297 X306 X308 X314
s1 0 1 0 0 0 1 0 0 0 0 0 0 0 0
s2 0 0 0 0 1 0 0 0 0 0 0 0 1 0
s3 0 1 0 0 0 0 0 0 0 0 0 0 1 0
s4 1 0 0 0 1 0 0 0 0 1 0 0 0 0
I used this code:
temp=list(NULL)
for(i in 1:5) {temp[i]<-sample(Mydata,5, replace=F)} show(temp)
but I get the following error:
"number of items to replace is not a multiple of replacement length"
any idea why I get this eeror message and how can I fix it?
Thanks a lot.
--
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http://www.nabble.com/Help-Help-with-sampling-tp19994275p19994275.html
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Alex99 wrote:> Hi everyone, > > I have a dataset(named "Mydata") which includes 4 different variables named; > s1,s2,s3,s4 .Each variable(symptom) has 14 patients. > I need to use random sampling to make, 5 different samples from my data with > 5 patients in each sample. i.e. using all 4 variables I need to make 5 > different samples by changing patients(with 5 patients in each sample). > > > X8 X9 X10 X102 X110 X177 X283 X284 X286 X292 X297 X306 X308 X314 > s1 0 1 0 0 0 1 0 0 0 0 0 0 0 0 > s2 0 0 0 0 1 0 0 0 0 0 0 0 1 0 > s3 0 1 0 0 0 0 0 0 0 0 0 0 1 0 > s4 1 0 0 0 1 0 0 0 0 1 0 0 0 0 > > > I used this code: > > temp=list(NULL) > for(i in 1:5) {temp[i]<-sample(Mydata,5, replace=F)} show(temp) > > but I get the following error: > "number of items to replace is not a multiple of replacement length" > > any idea why I get this eeror message and how can I fix it? > Thanks a lot. > >The direct cause is that you are not using temp[[i]]<-, but I don't think that sample() construct does what I think you think it does either. You might want to use replicate() instead, as in replicate(2,airquality[sample(1:153,5, replace=F),], simplify=F) -- O__ ---- Peter Dalgaard ?ster Farimagsgade 5, Entr.B c/ /'_ --- Dept. of Biostatistics PO Box 2099, 1014 Cph. K (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - (p.dalgaard at biostat.ku.dk) FAX: (+45) 35327907
Dear Alex,
Is this what you want?
# Data set
my=read.table(textConnection("
X8 X9 X10 X102 X110 X177 X283 X284 X286 X292 X297 X306 X308 X314
0 1 0 0 0 1 0 0 0 0 0 0 0 0
0 0 0 0 1 0 0 0 0 0 0 0 1 0
0 1 0 0 0 0 0 0 0 0 0 0 1 0
1 0 0 0 1 0 0 0 0 1 0 0 0
0"),header=TRUE)
closeAllConnections()
rownames(my)=paste('s',1:4,sep="")
# Samples
res=list()
for(i in 1:5) res[[i]]<- my[,sample(colnames(my),5)]
res
HTH,
Jorge
On Wed, Oct 15, 2008 at 10:07 AM, Alex99 <loyola9988@yahoo.com> wrote:
>
> Hi everyone,
>
> I have a dataset(named "Mydata") which includes 4 different
variables
> named;
> s1,s2,s3,s4 .Each variable(symptom) has 14 patients.
> I need to use random sampling to make, 5 different samples from my data
> with
> 5 patients in each sample. i.e. using all 4 variables I need to make 5
> different samples by changing patients(with 5 patients in each sample).
>
>
> X8 X9 X10 X102 X110 X177 X283 X284 X286 X292 X297 X306 X308 X314
> s1 0 1 0 0 0 1 0 0 0 0 0 0 0 0
> s2 0 0 0 0 1 0 0 0 0 0 0 0 1 0
> s3 0 1 0 0 0 0 0 0 0 0 0 0 1 0
> s4 1 0 0 0 1 0 0 0 0 1 0 0 0 0
>
>
> I used this code:
>
> temp=list(NULL)
> for(i in 1:5) {temp[i]<-sample(Mydata,5, replace=F)} show(temp)
>
> but I get the following error:
> "number of items to replace is not a multiple of replacement
length"
>
> any idea why I get this eeror message and how can I fix it?
> Thanks a lot.
>
> --
> View this message in context:
> http://www.nabble.com/Help-Help-with-sampling-tp19994275p19994275.html
> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
> R-help@r-project.org mailing list
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> PLEASE do read the posting guide
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>
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