[R] Simplifying particular piece of code

[Gustaf Rydevik]

On Wed, Mar 31, 2010 at 5:11 PM, Sergey Goriatchev <sergeyg at gmail.com> wrote:
> but
>
> data <- merge(data,data.list)
>
> works.
>
> Neither data or data.list is a list, so do.call does not work.
> I am very weak on lists, never used them before
>
> Best,
> Sergey

Hej Sergey,

Ok; I was wondering if the apply thing would work. Cool that merge
would be clever enough to append a matrix. I'm guessing that you've
got what you needed then? For reference,  (and for the general list) I
had changed the  code  before Sergeys response, replacing apply() with
lapply(). That code follows below.
Best regards,
Gustaf


-----------------------------
cnames <- c("BMM", "GM1", "IYC", "FCA", "IMM", "BME", "CRT", "GTF",
"ERU", "ERE", "EPT", "EVA", "EMT", "EMM", "EMV", "ETM")
AVnames <- paste(cnames, ".AV120", sep="")
SDnames <- paste(cnames, ".SD120", sep="")
a <- zoo(matrix(rep(seq(from=160, to=10, by=-10), 1000), ncol=16, byrow=TRUE))
colnames(a) <- AVnames
b <- zoo(matrix(rep(2, 16000), ncol=16))
colnames(b) <- SDnames
data <- merge(a, b)
MyFunc <- function(x, ret, stdev){
       if(any(is.na(c(x[ret], x[stdev])))){
               return(NA)
       }else{
               return(x[ret]/x[stdev])
       }
}
names.df<-data.frame(rbind(SRnames,AVnames,SDnames))
func <- function(.names){
       apply(data, 1, MyFunc, ret=.names[2], stdev=.names[3])
}
data.list<-lapply(names.df, func)
mrets<-do.call("merge",c(list(data),data.list))









On Wed, Mar 31, 2010 at 12:33, Gustaf Rydevik <gustaf.rydevik at gmail.com> wrote:
> How about this (not tested, since you did not provide example data nor
> function code):
>
> ---------------------------------------
>
> SRnames <- paste(colnames.mrets, ".SR", sep="")
> AVnames <- paste(colnames.mrets, ".AV120", sep="")
> SDnames <- paste(colnames.mrets, ".SD120", sep="")
> names.matrix<-cbind(SRnames,AVnames,SDnames)
>
> mrets.list<-apply(names.matrix,1,function(.names){
> apply(mrets,1,MyFunc,ret=.names[2],stdev=.names[3]}
> )
> names(mrets.list)<-names.matrix[,1]
> mrets<-do.call("merge",mrets.list)
>
> -------------------------------------------------
> ?
> /Gustaf
>
> On Wed, Mar 31, 2010 at 12:10 PM, Sergey Goriatchev <sergeyg at gmail.com> wrote:
>> Hello, everyone
>>
>> I have a piece of code that looks like this:
>>
>> mrets <- merge(mrets, BMM.SR=apply(mrets, 1, MyFunc, ret="BMM.AV120",
>> stdev="BMM.SD120"))
>> mrets <- merge(mrets, GM1.SR=apply(mrets, 1, MyFunc, ret="GM1.AV120",
>> stdev="GM1.SD120"))
>> mrets <- merge(mrets, IYC.SR=apply(mrets, 1, MyFunc, ret="IYC.AV120",
>> stdev="IYC.SD120"))
>> mrets <- merge(mrets, FCA.SR=apply(mrets, 1, MyFunc, ret="FCA.AV120",
>> stdev="FCA.SD120"))
>> mrets <- merge(mrets, IMM.SR=apply(mrets, 1, MyFunc, ret="IMM.AV120",
>> stdev="IMM.SD120"))
>> mrets <- merge(mrets, BME.SR=apply(mrets, 1, MyFunc, ret="BME.AV120",
>> stdev="BME.SD120"))
>> mrets <- merge(mrets, CRT.SR=apply(mrets, 1, MyFunc, ret="CRT.AV120",
>> stdev="CRT.SD120"))
>> mrets <- merge(mrets, GTF.SR=apply(mrets, 1, MyFunc, ret="GTF.AV120",
>> stdev="GTF.SD120"))
>> mrets <- merge(mrets, ERU.SR=apply(mrets, 1, MyFunc, ret="ERU.AV120",
>> stdev="ERU.SD120"))
>> mrets <- merge(mrets, ERE.SR=apply(mrets, 1, MyFunc, ret="ERE.AV120",
>> stdev="ERE.SD120"))
>> mrets <- merge(mrets, EPT.SR=apply(mrets, 1, MyFunc, ret="EPT.AV120",
>> stdev="EPT.SD120"))
>> mrets <- merge(mrets, EVA.SR=apply(mrets, 1, MyFunc, ret="EVA.AV120",
>> stdev="EVA.SD120"))
>> mrets <- merge(mrets, EMT.SR=apply(mrets, 1, MyFunc, ret="EMT.AV120",
>> stdev="EMT.SD120"))
>> mrets <- merge(mrets, EMM.SR=apply(mrets, 1, MyFunc, ret="EMM.AV120",
>> stdev="EMM.SD120"))
>> mrets <- merge(mrets, EMV.SR=apply(mrets, 1, MyFunc, ret="EMV.AV120",
>> stdev="EMV.SD120"))
>> mrets <- merge(mrets, ETM.SR=apply(mrets, 1, MyFunc, ret="ETM.AV120",
>> stdev="ETM.SD120"))
>>
>> Is there a way to simplify this, some sort of loop?
>> mrets is a zoo object.
>> .AV120 and .SD120 are columns in this object.
>> I need the exact .SR column names.
>>
>> This does not work:
>> SRnames <- paste(colnames.mrets, ".SR", sep="")
>> AVnames <- paste(colnames.mrets, ".AV120", sep="")
>> SDnames <- paste(colnames.mrets, ".SD120", sep="")
>>
>> for(i in seq(SRnames)){
>> mrets <- merge(mrets, SRnames[i]=apply(mrets, 1, MyFunc,
>> ret=AVnames[i], stdev=SDnames[i]))
>> }
>>
>>
>> Help much appreciated.
>>
>> Regards,
>> Sergey
>>
>>
>> --
>> Simplicity is the last step of art./Bruce Lee
>> The more you know, the more you know you don't know. /Myself
>>
>> I'm not young enough to know everything. /Oscar Wilde
>> Experience is one thing you can't get for nothing. /Oscar Wilde
>> When you are finished changing, you're finished. /Benjamin Franklin
>> Luck is where preparation meets opportunity. /George Patten
>>
>> Kniven skärpes bara mot stenen.
>>
>> ______________________________________________
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>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>>
>
>
-- 
Gustaf Rydevik, M.Sci.
tel: +46(0)703 051 451
address:Essingetorget 40,112 66 Stockholm, SE
skype:gustaf_rydevik