Table frequency numerical category operations function - r

Question

I am trying to learn how to write functions in R and I have a very specific question regarding the use of table and how to treat the "levels variable".
My original problem is to write a cumulative hazard function. My function basically does this:
Example: data x= c(1,1,2,2,2,3,14,25) which has 8 observations/times
From a vector 8 observations do the following operation for F(14)= 2/8 + 3/6+ 1/3+ 1/2
for F(2)= 2/8+3/6, so on.
Basically I want the sum of: (how many observations have time i)/(how many observations have time greater than or equal to i)
So for i=2, I have two fractions: 2/(8)+ 3/(6), because there are 6 observations with time i equal to 2 or more.
Specifically I was using the function table. However, this function gives me the frequencies and treats the value associated with the frequency as a level and not as a number.
For my data I have 5 levels: 1,2,3,14,15 but when I try to do operations like:
v<-c(1,2,3,14,15)
ta<-as.data.frame(table(v))
as.numeric(ta$v)<14
[1] TRUE TRUE TRUE TRUE TRUE
However, I want the result to be TRUE TRUE TRUE FALSE FALSE. I want the variables in table() to be treated as numbers.
How can I do that?
Just for the sake to see what I am doing, my extra code is below. It works well without the censoring, but this part is key for me to advance with censoring.
cumh<-function (x,t,y=rep(1,length(x))){
le<-length(x)
#Sum comparison of terms
isum<-sum(x<=t)
#Collapse table
ta<-as.data.frame((table(x)))
ta$cum<-cumsum(ta$Freq)
ta$den<-le
for (j in 1:(nrow(ta)-1)) {
ta$den[j+1]<-le-ta$cum[j]
}
ind<-isum>=ta$cum
#correction for right censor:
ta2<-as.data.frame(table(y*x))
cumhaz<-sum(ind*ta2$Freq/ta$den)
return(cumhaz)}

Answer 1

Here is one method using sapply and table
x <- c(1,1,2,2,2,3,14,25)
myTab <- table(x)
myTab / sapply(seq_along(myTab), function(i) sum(tail(c(0, myTab), -i)))
x
1 2 3 14 25
0.2500000 0.5000000 0.3333333 0.5000000 1.0000000
Here, tail successively removes values from the beginning of x. The remaining values are summed together. sapply does this for values from the beginning of x to the final value. To accomplish this, I pre-pended 0 to x. The summations then divide x to return the proportions.