R - Subsetting to group of matrices based on a condition

Question

I am trying to subset a matrix based on a specific value in a column. But I want my subsets in a number of separate matrices. For eg, say I have a matrix ccc which is

aaa=c(1,1,1,2,5,1,2,1,1,3,1,1,1,1,1,1,4)
bbb=c(4,4,4,4,3,3,3,3,2,2,2,2,3,4,5,6,7)
ccc=cbind(aaa,bbb)

I want to subset using a condition which is ccc[,1]==1 and at the same time I want the subset to be divided into several matrices separated by a breaking point. The breaks are based on runs of aaa==1. To make it clear I need my outputs in the following way,

ddd1
     aaa bbb
[1,]   1   4
[2,]   1   4
[3,]   1   4

ddd2
aaa bbb 
  1   3 

ddd3
     aaa bbb
[1,]   1   3
[2,]   1   2

ddd4
     aaa bbb
[1,]   1   2
[2,]   1   2
[3,]   1   3
[4,]   1   4
[5,]   1   5
[6,]   1   6

ddd1,..,ddd4 being the subset matrices. I hope I made it clear. Any suggestion how to do it?

Answer 1

Use split and cumsum:

ccc <- data.frame(ccc)
split(ccc[ccc$aaa==1,], cumsum(ccc$aaa!=1)[ccc$aaa==1])

#$`0`
#  aaa bbb
#1   1   4
#2   1   4
#3   1   4
#
#$`2`
#  aaa bbb
#6   1   3
# 
#$`3`
#  aaa bbb
#8   1   3
#9   1   2
# 
#$`4`
#   aaa bbb
#11   1   2
#12   1   2
#13   1   3
#14   1   4
#15   1   5
#16   1   6