Replacing elements of a vector

Question

I have the following string:

string <- c("100 this is 100 test 100 string")

I would like to replace the 100's in the above string with elements of another vector:

replacement <- c(1000,2000,3000)

The first 100 of string should be replace by 1000, second 100 by 2000 and so on. The resulting string should look as follows:

result <- c("1000 this is 2000 test 3000 string")

Is there an efficient way to do this in R?

Thank you.

Ravi

Answer 1

one way:

> cs <- strsplit(string," ")[[1]]
> cs[cs == "100"] <- replacement
> cat(cs)
1000 this is 2000 test 3000 string

Answer 2

Not very elegant, but this should do..

string <- c("100 this is 100 test 100 string")
temp <- unlist(strsplit(string, split = "\\s+"))
replacement <- c(1000, 2000, 3000)
temp[temp == "100"] <- replacement
result <- paste(temp, collapse = " ")

result
## [1] "1000 this is 2000 test 3000 string"