R Subsetting vector with logical matrix

Question

I would like to subset a numeric vector with a logical matrix in the following way: Given a vector y

y <- c(4,8,1,3,5,7)

and a logical matrix lmat

lmat <- t(matrix(c(FALSE, FALSE, FALSE, FALSE, FALSE, FALSE,
TRUE,  FALSE, FALSE, FALSE, FALSE, FALSE,
FALSE, TRUE,  FALSE, FALSE, FALSE, FALSE,
TRUE,  TRUE,  FALSE, FALSE, FALSE, FALSE,
FALSE, FALSE,  TRUE, FALSE, FALSE, FALSE,
TRUE,  FALSE,  TRUE, FALSE, FALSE, FALSE),  ncol = 6))

which looks like this

> lmat
      [,1]  [,2]  [,3]  [,4]  [,5]  [,6]
[1,] FALSE FALSE FALSE FALSE FALSE FALSE
[2,]  TRUE FALSE FALSE FALSE FALSE FALSE
[3,] FALSE  TRUE FALSE FALSE FALSE FALSE
[4,]  TRUE  TRUE FALSE FALSE FALSE FALSE
[5,] FALSE FALSE  TRUE FALSE FALSE FALSE
[6,]  TRUE FALSE  TRUE FALSE FALSE FALSE

I want to apply some function x() that subsets y according to the rows of lmat and returns a list. So x(y) would return:

[[1]]
numeric(0)

[[2]]
[1] 4 9

[[3]]
[1] 8

[[4]]
[1] 4 8 9

[[5]]
[1] 1

[[6]]
[1] 4 1 9

I'm still learning the apply functions and I suspect this is somehow possible with apply or sapply despite trying to use one of those functions to get the result I want. I basically want

y[lmat[1,]]
y[lmat[2,]]
y[lmat[3,]]

etc....

but lmat is large and I think there is a way to do with without a loop. Thanks.

Answer 1

lapply(1:nrow(lmat), function(i) y[lmat[i,]])
#OR
apply(lmat, 1, function(x) y[x])