CODEWITHSUNDEEP
r
Devang Akotia
Devang Akotia

Reputation: 119

create new dataframe from missing values

Consider a vector x:

x <- c(0, 5, 10, 25, 30)

I would like to create a new vector with "missing values," which means all the values that were "skipped" if I were to have a sequence with intervals of 5.

So for this example, the output shouldbe:

xna <- c(15, 20)

Additionally, I would have to make a function so that I can do this to any vector x.

nats <- function(x){
  lastvalue <- x[length(x)]
  firstvalue <-x[1]
  xseq <- seq(firstvalue, lastvalue, 5)
  for i in xseq {
     # if x is not in x seq put it into a vecotr xna # 
   }
xna
}

I really have no idea how to do this. Would really appreciate suggestions or if there is already a function that can do this.

Please help,

Upvotes: 0

Views: 62

Answers (3)

Xiongbing Jin
Xiongbing Jin

Reputation: 12107

Using %in% operator. See https://stat.ethz.ch/R-manual/R-devel/library/base/html/match.html

xna <- xseq[!xseq%in%x]

Upvotes: 0

Ronak Shah
Ronak Shah

Reputation: 389275

If you need as a function, 

nats  <- function(x, interval){
   lastvalue <- x[length(x)]
   firstvalue <-x[1]
   xseq <- seq(firstvalue, lastvalue, interval)
   xna <- xseq[!xseq %in% x]
   return(xna)
}

x <- c(0,5,10, 15,25,30)
nats(x, 5)
#[1] 20
x <- c(3, 6,18)
nats(x, 3)
#[1]  9 12 15

Upvotes: 3

Maurits Evers
Maurits Evers

Reputation: 50738

Solution in base R (see ?setdiff)

# Your data
x <- c(0, 5, 10, 25, 30)

# Your sequence
y <- seq(0, max(x), by = 5);

# "Skipped" values
s <- setdiff(y, x);
print(s);
[1] 15 20

Upvotes: 1

Related Questions