r - Indexing for loops in lists consisting of matrices -

i struggling indexing correctly piece of code below. perhaps set of data not ideal either.

first, want compare values between 2 columns in abcd b , d , each set of generated randomnum rows. if row value in randomnum greater b abcd value, should = 0, if else should = 1 outcome list 2 matrices, 1 comparing column b , 1 column or vector d against each set of row values (treated vectors) in randomnum using criteria described above. outcome list have 2 matrices dimensions of nv * rp , saved list udrandomnum. then, want take difference between outcome value 0 or 1 in udrandomnum row or column of 3 , each time deduct columns b , d in abcd. outcome saved in differences again have 2 matrices, each 1 comparing set of vectors of 3 against same column b , d abcd. hope makes sense.

set.seed(101) <- c(0.1,0.2,0.3) b <- c(0.8,0.2,0.5) c <- c(0.4,0.9,1.0) d <- c(0.7,0.9,0.2) ab <- cbind(a,b) cd <- cbind(c,d) abcd <- list(ab,cd)  rp <- 100 nv <- length(a)  randomnum <- vector("list",length(a))  # draw random values between 0 , 1 uniform distribution (i in 1:length(a)) {         randomnum[[i]] <- t(replicate(rp, runif(nv, min=0,max=1))) } 

the problematic piece starts here:

udrandomnum <- vector("list",length(abcd))  (i in 1:length(abcd)) {         udrandomnum[[i]] <- randomnum[[i]][i] <                  abcd[[i]][,2][col(randomnum[[i]])]+0 }  # later, want take difference between outcomes (1 or 0)  differences <- vector("list",length(abcd))  (i in 1:length(abcd)) {             differences[[i]] <- abs(sweep(udrandomnum,2,abcd[,2])) } 

so randomnum have outcome starts with:

[[1]]               [,1]       [,2]        [,3]   [1,] 0.076929106 0.42883794 0.502711454   [2,] 0.254765247 0.57422550 0.578616861   [3,] 0.270195792 0.30920944 0.094095268   [4,] 0.512404975 0.97536980 0.082336057   ... 

i compare b: 0.8,0.2,0.5 (if value in randomnum > b 0, else 1)

udrandomnum:

[[1]]        [,1]  [,2]  [,3]   [1,] 1     0     0   [2,] 1     0     0    [3,] 1     0     1    [4,] 1     0     1   ... 

and deduct values in udrandomnum b outcome in differences following (whatever results typed equation convenience, should number resulting equation)

  [[1]]        [,1]               [,2]              [,3]   [1,] abs(1-0.076929106) abs(0-0.42883794) abs(0-0.502711454)   [2,] abs(1-0.254765247) abs(0-0.57422550) abs(0-0.578616861)   [3,] abs(1-0.270195792) abs(0-0.30920944) abs(1-0.094095268)   [4,] abs(1-0.512404975) abs(0-0.97536980) abs(1-0.082336057)   ... 

udrandomnum <- vector("list",length(abcd))  (i in 1:length(abcd)) {         udrandomnum[[i]] <- randomnum[[1]] <            matrix(abcd[[i]][,2][col(randomnum[[i]])], ncol=3) }  differences <- vector("list",length(abcd))  (i in 1:length(abcd)) {             differences[[i]] <- abs(udrandomnum[[i]] - randomnum[[i]]) } 

explanation

with udrandomnum list, try changing abcd b , d columns matrices match dimensions of randomnum. , differences list, r automatically coerce true , false results 1 , 0 when subtract 2 matrices udrandomnum , randomnum.