R help - Apr 2013 - Distance matrices Combinations

Dear UseRs,
MY PROBLEM IS A SMALL PIECE OF A REAL BIG AND A COMPLICATED PROBLEM. IF I
DELIBERATE IN A VERY SIMPLE WAY THEN ALL I
WANT IS TO PUT ALL THE POSSIBLE COMBINATIONS OF 75 DISTANCE MATRICES (BY TAKING
4 MATRICES, MORE COMMONLY 75C4), in the following equation.


t<-as.matrix((MAT1)^2+(MAT2)^2+(MAT3)^2+(MAT4)^2+,upper=T,diag=T))

Then "1215450" values of "t"(one for each combination)
should one by one be inculcated in the following loop(to calculate the
"o" value) and in the end want those 10 combinations of distance
matrices which have lowest "o" values.

e <- vector("list", 124)

w<-sqrt(t)

mat1<-w

for (i in 1:124){

r<-matrix(sort(mat1[i,],index.return=TRUE)$ix,ncol=1)

u<-r[c(2,3,4,5,6),1]

mata<-m[,c(u)]				##(shifted)

amata<-apply(mata,1,mean)

amata<-data.frame(amata)

aavg<-as.matrix(amata, ncol=1)

b<-aavg

e[[i]]<-print(sum(abs(b-m[,i])))

}

x<-do.call(rbind,e)

Y<-x

z <- apply(Y,2,sd)

o<-mean(Y)

Does my question make any scene?
Thanks in advance
Elisa 		 	   		  
	[[alternative HTML version deleted]]

HI,

Your code is not very clear. 

mata<-m[,c(u)]??? ?? # assume that "m" is "mat1" or
"w" (as "m" was not defined)

#also assume that "124" as nrow? of each matrix 
# For 10 distance matrices (#10C4)
set.seed(25)
lst1<- lapply(1:10,function(i)
dist(matrix(sample(1:50,5*124,replace=TRUE),nrow=124)))
names(lst1)<- seq_along(lst1)
?lst2<-lapply(seq_len(ncol(combn(names(lst1),4))),function(i)
{x<-combn(names(lst1),4)[,i];as.matrix((lst1[[x[1]]])^2+(lst1[[x[2]]])^2+(lst1[[x[3]]])^2+(lst1[[x[4]]])^2)})
?X<- do.call(cbind,lapply(lst2,function(x) {w<-
sqrt(x);do.call(rbind,lapply(seq_len(nrow(w)),function(i)
{r<-matrix(sort(x[i,],index.return=TRUE)$ix,ncol=1); u<- r[2:6,];
mata<-w[,u];b<- matrix(apply(mata,1,mean),ncol=1);
e<-sum(abs(b-w[,i]))}))}))
?o<-mean(apply(X,2,sd))
?o
#[1] 268.7831
A.K.

----- Original Message -----
From: eliza botto <eliza_botto at hotmail.com>
To: "r-help at r-project.org" <r-help at r-project.org>
Cc: 
Sent: Wednesday, April 24, 2013 2:07 PM
Subject: [R] Distance matrices Combinations

Dear UseRs,
MY PROBLEM IS A SMALL PIECE OF A REAL BIG AND A COMPLICATED PROBLEM. IF I
DELIBERATE IN A VERY SIMPLE WAY THEN ALL I
WANT IS TO PUT ALL THE POSSIBLE COMBINATIONS OF 75 DISTANCE MATRICES (BY TAKING
4 MATRICES, MORE COMMONLY 75C4), in the following equation.


t<-as.matrix((MAT1)^2+(MAT2)^2+(MAT3)^2+(MAT4)^2+,upper=T,diag=T))

Then "1215450" values of "t"(one for each combination)
should one by one be inculcated in the following loop(to calculate the
"o" value) and in the end want those 10 combinations of distance
matrices which have lowest "o" values.

e <- vector("list", 124)

w<-sqrt(t)

mat1<-w

for (i in 1:124){

r<-matrix(sort(mat1[i,],index.return=TRUE)$ix,ncol=1)

u<-r[c(2,3,4,5,6),1]

mata<-m[,c(u)]??? ??? ??? ??? ##(shifted)

amata<-apply(mata,1,mean)

amata<-data.frame(amata)

aavg<-as.matrix(amata, ncol=1)

b<-aavg

e[[i]]<-print(sum(abs(b-m[,i])))

}

x<-do.call(rbind,e)

Y<-x

z <- apply(Y,2,sd)

o<-mean(Y)

Does my question make any scene?
Thanks in advance
Elisa ??? ???  ??? ?  ??? ??? ? 
??? [[alternative HTML version deleted]]

______________________________________________
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

Hi,
Do you want this?

el<- matrix(1:100,ncol=20)
?set.seed(25)
?el1<- matrix(sample(1:100,20,replace=TRUE),ncol=1)
indx<-sort(el1,index.return=TRUE)$ix[1:3]

?list(el[,indx],sort(el1)[1:3])
#[[1]]
?# ?? [,1] [,2] [,3]
#[1,]?? 41?? 21?? 11
#[2,]?? 42?? 22?? 12
#[3,]?? 43?? 23?? 13
#[4,]?? 44?? 24?? 14
#[5,]?? 45?? 25?? 15
#
#[[2]]
#[1]? 7 13 15
A.K.



________________________________
From: eliza botto <eliza_botto at hotmail.com>
To: "smartpink111 at yahoo.com" <smartpink111 at yahoo.com> 
Sent: Thursday, April 25, 2013 4:45 PM
Subject: RE: [R] Distance matrices Combinations




dear arun,
I will see through it thoroughly if you give some 10 mins. Meanwhile can you
please tell me that how we can change the following of your codes so that in
"el1" we could see the values not the indexes??

thanks,
Elisa

el1<-matrix(o,ncol=1)
indx<-sort(el1,index.return=F)$ix[1:3]
list(el[,indx],indx)