Ranks and identification of elements in r

Question

I have two vectors with different elements, say x=c(1,3,4) , y= c(2,9)

I want a vector of ranges that identifies me the elements of vector x with 1 and those of y with 0, ie

(1,2,3,4,9) -----> (1,0,1,1,0)

How could you get the vector of zeros and ones (1,0,1,1,0) in r?

Thanks

This seems to be off topic because it deals mainly with R programming. — Michael R. Chernick, Apr 04 '17 at 11:49

score 1 · Answer 1 · answered Apr 04 '17 at 07:51

The following option surely isn't numerically optimal, but it's the most simple and direct one:

a<-c(1,2,3,4)
b<-c(5,6,7,8)
f<-function(vec0,vec1,inp)
{
  out<-rep(NA,length(inp))       #NA if input elements in neither vector

  for(i in 1:length(inp))
  {                                      #Logical values coerced to 0 and 1 at first, then
    if(sum(inp[i]==vec0))(out[i]<-0);    #summed up and if sum != 0 coerced to logical "TRUE"
  }

  for(i in 1:length(inp))
  {
    if(sum(inp[i]==vec1))(out[i]<-1);
  }

  return (out)
}

Works just fine:

> f(vec0=a,vec1=b,inp=c(1,6,4,8,2,4,8,7,10))
[1]  0  1  0  1  0  0  1  1 NA

score 0 · Accepted Answer · edited Apr 04 '17 at 14:16

first you define a function that do that

blah <- function( vector,
                 x=c(1,3,4), 
                 y= c(2,9)){
outVector <- rep(x = NA, times = length(vector))
outVector[vector %in% x] <- 1
outVector[vector %in% y] <- 0
return(outVector)  
}

then you can use the function:

blah(vector = 1:9)
blah(vector = c(1,2,3,4,9))

you can also change the value of x & y

blah(vector = 1:10,x = c(1:5*2), y = c((1:5*2)-1 ))

Ranks and identification of elements in r

2 Answers2