Hi Christian: Many thank for the code.
But I am afraid that your code still has a problem in terms of providing correct correlation. For example, if you look at the correlation between DataArray_1["A2","B1","D1",] and DataArray_2["A2","C1","D1",] after running your code, you will notice that this is actually the correlation between DataArray_1["A2","B1","D1",] and DataArray_2["A1",C1","D1",] and so on. The code gives the correct result only in case where elements corresponding to "A1" & "D1" are involved in DataArray_1 & DataArray_2. The problem is in Correl<-Correl[1:length(c),,,] We need to select elements of Correl more carefully to reach a proper solution. Thanks, Sauvik On Wed, Jul 29, 2009 at 11:41 PM, Poersching <poerschin...@web.de> wrote: > Hey, > i have forgotten to generalize the code so > > Correl<-Correl[1:4,,,] > > must be > > Correl<-Correl[1:length(c),,,] > > it's because the comparison levels. I think you don't want the > correlation betweeen A1, B1, D1 and A2, C1, D1 , > but between A1, B1, D1 and A1, C1, D1 or between A1, B1, D1 and A1, C2, D1. > So the "1:length(c)" writes only the correlation between the B and C out > of the whole correlation array. > That's also why the sequence in the second apply function is changed. > > Regards Christian. > > Poersching schrieb: > > Hey, > > I think I have a solution for your problem: > > > > Correl<-apply(DataArray_1,1:3, function(d1) > > apply(DataArray_2,c(2,1,3), function(d) cor(d1,d)) > > ) > > Correl<-Correl[1:4,,,] > > dimnames(Correl)[[1]]<-c > > Correl<-aperm(Correl,c(2,3,1,4)) > > > > This one should work. :-) > > > > Best Regards, > > Christian > > > > Sauvik De schrieb: > > > >> Hi there, > >> > >> Thanks again for your reply. I know for-loop is always a solution to > >> my problem and I had already coded using for-loop. But the number of > >> levels for each dimension is large enough in actual problem and hence > >> it was time-consuming. > >> So, I was just wondering if there are any other alternative way-outs > >> to solving my problem. That's why I tried with apply functions > >> (sapply)assuming that this might work out faster even fractionally as > >> compared to for-loop. > >> > >> Cheers, > >> Sauvik > >> > >> On Mon, Jul 27, 2009 at 12:28 AM, Poersching <poerschin...@web.de > >> <mailto:poerschin...@web.de>> wrote: > >> > >> Sauvik De schrieb: > >> > >>> Hi: > >>> Lots of thanks for your valuable time! > >>> > >>> But I am not sure how you would like to use the function in this > >>> situation. > >>> > >>> As I had mentioned that the first element of my output array > >>> should be like: > >>> > >>> > cor(DataArray_1[dimnames(Correl)[[1]][1],dimnames(Correl)[[2]][1],dimnames(Correl)[[4]][1],],DataArray_2[dimnames(Correl)[[1]][1],dimnames(Correl)[[3]][1],dimnames(Correl)[[4]][1],],use="pairwise.complete.obs") > >>> > >>> in my below code. > >>> > >>> and > >>> > >>> the output array of correlation I wish to get using "sapply" as > >>> follows: > >>> > >>> Correl = sapply(Correl,function(d) > >>> cor(DataArray_1[...],DataArray_2[...], > >>> use="pairwise.complete.obs")) > >>> > >>> So it would be of great help if you could kindly specify how to > >>> utilise your function "findIndex" in ... > >>> > >>> Apologies for all this! > >>> > >>> Thanks & Regards, > >>> Sauvik > >>> > >>> > >> Hey, > >> sorry, I haven't understood your problem last time, but now this > >> solution should solve your problem, so I hope. :-) > >> It's only a for to loop, but an apply function may work too. I > >> will think about this, but for now... ;-) > >> > >> la<-length(a) > >> lb<-length(b) > >> lc<-length(c) > >> ld<-length(d) > >> for (ia in 1:la) { > >> for (ib in 1:lb) { > >> for (ic in 1:lc) { > >> for (id in 1:ld) { > >> Correl[ia,ib,ic,id]<-cor( > >> DataArray_1[dimnames(Correl)[[1]][ia], > >> dimnames(Correl)[[2]][ib], > >> dimnames(Correl)[[4]][id],] > >> , > >> DataArray_2[dimnames(Correl)[[1]][ia], > >> dimnames(Correl)[[3]][ic], > >> dimnames(Correl)[[4]][id],] > >> , > >> use="pairwise.complete.obs") > >> } > >> } > >> } > >> } > >> ## with function findIndex you can find the dimensions with > >> ## i.e. cor values greater 0.5 or smaller -0.5, like: > >> findIndex(Correl,Correl[Correl>0.5]) > >> findIndex(Correl,Correl[Correl<(-0.5)]) > >> > >> I have changed the code of the function findIndex in line which > >> contents: el[j]<-which(is.element(data,element[j])) > >> > >> Rigards, > >> Christian > >> > >> > >>> On Sun, Jul 26, 2009 at 3:54 PM, Poersching<poerschin...@web.de > >>> <mailto:poerschin...@web.de>> wrote: > >>> > Sauvik De schrieb: > >>> > > >>> > Hi Gabor: > >>> > Many thanks for your prompt reply! > >>> > The code is fine. But I need it in more general form as I had > >>> mentioned that > >>> > I need to input any 0 to find its dimension-names. > >>> > > >>> > Actually, I was using "sapply" to calculate correlation and > >>> this idea was > >>> > required in the middle of correlation calculation. > >>> > I am providing the way I tried my calculation. > >>> > > >>> > a= c("A1","A2","A3","A4","A5") > >>> > b= c("B1","B2","B3") > >>> > c= c("C1","C2","C3","C4") > >>> > d= c("D1","D2") > >>> > e= c("E1","E2","E3","E4","E5","E6","E7","E8") > >>> > > >>> > DataArray_1 = array(c(rnorm(240)),dim=c(length(a),length(b), > >>> > length(d),length(e)),dimnames=list(a,b,d,e)) > >>> > DataArray_2 = array(c(rnorm(320)), dim=c(length(a),length(c), > >>> > length(d),length(e)),dimnames=list(a,c,d,e)) > >>> > > >>> > #Defining an empty array which will contain the correlation > >>> values (output > >>> > array) > >>> > Correl = array(NA, dim=c(length(a),length(b), > >>> > length(c),length(d)),dimnames=list(a,b,c,d)) > >>> > > >>> > #Calculating Correlation between attributes b & c over values of > e > >>> > Correl = sapply(Correl,function(d) > >>> cor(DataArray_1[...],DataArray_2[...], > >>> > use="pairwise.complete.obs")) > >>> > > >>> > This is where I get stuck. > >>> > In the above, d is acting as an element in the "Correl" array. > >>> Hence I need > >>> > to get the dimension-names for d. > >>> > > >>> > #The first element of Correl will be: > >>> > > >>> > cor(DataArray_1[dimnames(Correl)[[1]][1],dimnames(Correl)[[2]][1],dimnames(Correl)[[4]][1],],DataArray_2[dimnames(Correl)[[1]][1],dimnames(Correl)[[3]][1],dimnames(Correl)[[4]][1],],use="pairwise.complete.obs") > >>> > > >>> > So my problem boils down to extracting the dim-names in terms > >>> of element(d) > >>> > and not in terms of Correl (that I have mentioned as "..." in > >>> the above > >>> > code) > >>> > > >>> > My sincere thanks for your valuable time & suggestions. > >>> > > >>> > Many Thanks & Kind Regards, > >>> > Sauvik > >>> > > >>> > > >>> > On Sun, Jul 26, 2009 at 5:26 AM, Gabor Grothendieck > >>> <ggrothendi...@gmail.com <mailto:ggrothendi...@gmail.com> > >>> > > >>> > > >>> > wrote: > >>> > > >>> > > >>> > > >>> > > >>> > Try this: > >>> > > >>> > > >>> > > >>> > ix <- c(1, 3, 4, 2) > >>> > mapply("[", dimnames(mydatastructure), ix) > >>> > > >>> > > >>> > [1] "S1" "T3" "U4" "V2" > >>> > > >>> > > >>> > On Sat, Jul 25, 2009 at 5:12 PM, Sauvik > >>> De<sauvik.s...@gmail.com <mailto:sauvik.s...@gmail.com>> wrote: > >>> > > >>> > > >>> > Hi: > >>> > How can I extract the dimension-names of a pre-defined element in > a > >>> > multidimensional array in R ? > >>> > > >>> > A toy example is provided below: > >>> > I have a 4-dimensional array with each dimension having certain > >>> length. > >>> > > >>> > > >>> > In > >>> > > >>> > > >>> > the below example, "mydatastructure" explains the structure of > >>> my data. > >>> > > >>> > mydatastructure = array(0, > >>> > > >>> > > >>> > dim=c(length(b),length(z),length(x),length(d)), > >>> > > >>> > > >>> > dimnames=list(b,z,x,d)) > >>> > > >>> > where, > >>> > b=c("S1","S2","S3","S4","S5") > >>> > z=c("T1","T2", "T3") > >>> > x=c("U1","U2","U3","U4") > >>> > d=c("V1","V2") > >>> > > >>> > Clearly, "mydatastructure" contains many 0's. > >>> > Now how can I get the dimension-names of any particular 0 ? > >>> > That is, my input should be a particular 0 in the array > >>> "mydatastructure" > >>> > (Suppose this 0 corresponds to S1,T3,U4 & V2 in the array). Then > my > >>> > > >>> > > >>> > output > >>> > > >>> > > >>> > should be S1,T3,U4 & V2. > >>> > > >>> > The function "dimnames" didn't help me with the solution. > >>> > Any idea will greatly be appreciated. > >>> > > >>> > Thanks for your time! > >>> > > >>> > Kind Regards, > >>> > Sauvik > >>> > > >>> > [[alternative HTML version deleted]] > >>> > > >>> > ______________________________________________ > >>> > R-help@r-project.org <mailto:R-help@r-project.org> mailing list > >>> > 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. > >>> > > >>> > > >>> > > >>> > [[alternative HTML version deleted]] > >>> > > >>> > ______________________________________________ > >>> > R-help@r-project.org <mailto:R-help@r-project.org> mailing list > >>> > 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. > >>> > > >>> > > >>> > > >>> > Hey, > >>> > > >>> > I have spend some time to write a function, which should > >>> fulfill your needs. > >>> > so i hope ;-) > >>> > > >>> > findIndex<-function(data,element) { > >>> > ld<-length(data) > >>> > el<-which(is.element(data,element)) > >>> > lel<-length(el) > >>> > ndim<-length(dim(data)) > >>> > ind<-array(,dim=c(lel,ndim),dimnames=list(el,1:ndim)) > >>> > precomma<-"" > >>> > tempdata<-data > >>> > tempel<-el > >>> > for (j in 1:lel) { > >>> > data<-tempdata > >>> > el<-tempel > >>> > ld<-length(data) > >>> > for (i in ndim:1) { > >>> > ratio<-el[j]/(ld/dim(data)[i]) > >>> > if (ratio-trunc(ratio)>0) { > >>> > ind[j,i]<-trunc(ratio)+1 > >>> > } else { > >>> > ind[j,i]<-trunc(ratio) > >>> > } > >>> > if (length(dim(data))>1) { > >>> > k<-1 > >>> > while (k>=1 & k<=(i-1)) { > >>> > precomma<-paste(precomma,",",sep="") > >>> > k<-k+1 > >>> > } > >>> > > >>> > > >>> > data<-as.array(eval(parse(text=paste("data[",precomma,ind[j,i],"]",sep="")))) > >>> > precomma<-"" > >>> > ld<-length(data) > >>> > el[j]<-which(is.element(data,element[j])) > >>> > >>> > } > >>> > } > >>> > } > >>> > return(ind) > >>> > } > >>> > > >>> > Regards, > >>> > Christian Porsche > >>> > > >>> > >>> > >> > > > > ______________________________________________ > > R-help@r-project.org mailing list > > 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. > > > > > > > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list 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.
