Vector analysis in R - r

Question

As inputs your function should take a vector of 0s and 1s;
Every time you see a sequence of 1s in the data you need to increase the number of children by 1;
Be careful with the two subsequent sequences of 1s, where the difference between them is less than 5 (i.e. when there are less than 5 0s in between them, then it is the same child and not a new child);
To help you social planner provides some examples of what your function should return:
#Input: c(1,1,1,1,0,0,0,0)
#Output: 1 1 1 1 1 1 1 1
#Input: c(0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1)
#Output: 0 0 0 0 1 1 1 1 1 1 1 1 1 2 2 2
#Input: c(0,0,0,0,1,1,1,1,0,0,1,1,0,0,0,1,1,0,0,0,0,1,1,0,0,0,0,0,1)
#Output: 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2
Functions, which might be helpful:
diff()
cumsum()
which()
rle()
I dont quite understand how to approach the question, my thoughts on this are using diff function after the cumsum as it will help me to sustain a row of 1s but in this scenario i am loosing the length of vector (it obviously becomes shorter) also #rle$lenght seems to help me to detect gaps of length 5 or more to turn 1s into 2s. Sorry for this question I am only a beginner

Answer 1

I make use of which function in r (https://www.r-bloggers.com/which-function-in-r/) and run length encoding (http://www.cookbook-r.com/Manipulating_data/Finding_sequences_of_identical_values/). Here's my attempt:
vector_analyse <- function(sample_vector){
# ----------------------------------------------------------------------------
# Signature: vector --> vector
# Author: kon_u
# Description: Given a sample vector of 0s and 1s, return a sequence of 1s in
# the data you need to increase the number of children by 1 (when there are less
# 5 0s in between them, then it is the same child and not a new child)
# ----------------------------------------------------------------------------
# ----------------------------------------------------------------------------
# Run Length Encoding gives a list of length and values
# ----------------------------------------------------------------------------
rle_object <- rle(sample_vector)
x <- rle_object$lengths # original length
y <- rle_object$values # original values
z <- which(y == 1) # index of 1 in vector y
if (length(z) == 1){
invisible()
} else{
for (i in 2:length(z)){
if (x[z[i]-1] >= 5){
y[z[i]] = y[z[i]]
} else {
y[z[i]] = y[z[i]] - 1
}
}
}
y_cumsum = cumsum(y)
rle_object$values <- y_cumsum
new_vector = inverse.rle(rle_object)
return(new_vector)
}
vector_analyse(c(1,1,1,1,0,0,0,0)) # 1 1 1 1 1 1 1 1
vector_analyse(c(0,0,0,0,1,1,1,1,0,0,0,0,0,1,1,1)) # 0 0 0 0 1 1 1 1 1 1 1 1 1 2 2 2
vector_analyse(c(0,0,0,0,1,1,1,1,0,0,1,1,0,0,0,1,1,0,0,0,0,1,1,0,0,0,0,0,1)) # 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2