Order data frame rows according to vector with specific order

Try match:

df <- data.frame(name=letters[1:4], value=c(rep(TRUE, 2), rep(FALSE, 2)))
target <- c("b", "c", "a", "d")
df[match(target, df$name),]

  name value
2    b  TRUE
3    c FALSE
1    a  TRUE
4    d FALSE

It will work as long as your target contains exactly the same elements as df$name, and neither contain duplicate values.

From ?match:

match returns a vector of the positions of (first) matches of its first argument 
in its second.

Therefore match finds the row numbers that matches target's elements, and then we return df in that order.