Subsetting one matrix based in another matrix

2019-05-09 13:02发布

问题:

I would like to select the R based on G strings to obtain separated outputs with equal dimensions. This are my inputs:

R <- 'pr_id  sample1  sample2 sample3
            AX-1   100       120     130    
            AX-2   150       180     160
            AX-3   160       120     196'
R <- read.table(text=R, header=T)

G <- 'pr_id  sample1  sample2 sample3
            AX-1   AB       AA     AA    
            AX-2   BB       AB     NA
            AX-3   BB       AB     AA'
G <- read.table(text=G, header=T)

This are my expected outputs:

AA <- 'pr_id  sample1  sample2 sample3
            AX-1   NA       120     130    
            AX-2   NA       NA     NA
            AX-3   NA       NA     196'
AA <- read.table(text=AA, header=T)

AB <- 'pr_id  sample1  sample2 sample3
            AX-1   100       NA     NA    
            AX-2   NA       180     NA
            AX-3   NA       120     NA'
AB <- read.table(text=AB, header=T)

BB <- 'pr_id  sample1  sample2 sample3
            AX-1   NA       NA     NA    
            AX-2   150       NA     NA
            AX-3   160       NA     NA'
BB <- read.table(text=BB, header=T)

Some idea to perform it?

回答1:

We subset the 'G' from the 2nd column, convert to matrix, and split the sequence with the values in that, create a new matrix with NA ("G1") and using the index, we replace the values that corresponds to the "R" dataset values.

lapply(split(seq_along(as.matrix(G[-1])), 
       as.matrix(G[-1])), function(x) {
        G1 <- matrix(NA, ncol=ncol(G)-1, nrow=nrow(G), 
                   dimnames=list(NULL, names(G)[-1]))
        G1[x] <- as.matrix(R[-1])[x]
        data.frame(pr_id=R$pr_id, G1) })
#$AA
#  pr_id sample1 sample2 sample3
#1  AX-1      NA     120     130
#2  AX-2      NA      NA      NA
#3  AX-3      NA      NA     196

#$AB
#  pr_id sample1 sample2 sample3
#1  AX-1     100      NA      NA
#2  AX-2      NA     180      NA
#3  AX-3      NA     120      NA

#$BB
#  pr_id sample1 sample2 sample3
#1  AX-1      NA      NA      NA
#2  AX-2     150      NA      NA
#3  AX-3     160      NA      NA


回答2:

Another way:

lev<-setdiff(as.character(unique(unlist(G[-1]))),NA)
lapply(lev, function(x) {res<-G[-1]==x;res[!res]<-NA;cbind(R[1],res*R[-1])})


回答3:

row.names(R) <- R[[1]]; R <- as.matrix(R[-1])
row.names(G) <- G[[1]]; G <- as.matrix(G[-1])
AA <- ifelse(G=="AA", R, NA)
AB <- ifelse(G=="AB", R, NA)
BB <- ifelse(G=="BB", R, NA)

or with lapply() (for the last three lines):

lapply(c("AA", "AB", "BB"), function(x) ifelse(G==x, R, NA))


标签: r subset