r - apply formula for certain columns using other columns -

i have data frame

  dat = data.frame(type = c("a","a","b","b","c","c","d"), nexttype = c("a", "b","b", "c","c","d",na),                   = c(rep(0,7)),                   b = rep(0,7),                   c = rep(0,7) ,                   d = rep(0,7),                  stringsasfactors = f) dat   type nexttype b c d 1           0 0 0 0 2           b 0 0 0 0 3    b        b 0 0 0 0 4    b        c 0 0 0 0 5    c        c 0 0 0 0 6    c        d 0 0 0 0 7    d     <na> 0 0 0 0 

what's best way populate columns a, b , c , d 1 if column name (a, b, c, d etc...) = type = nexttype

so

column 1,0,0,0,0,0,0 column b 0,0,1,0,0,0,0 column c 0,0,0,0,1,0,0 column d 0,0,0,0,0,0,0 

note -- has dynamic. have 4 columns above a, b , c , d there can 10, 20 or number of columns.

use dplyr , tidyr:

library(dplyr); library(tidyr);  dat %>%      select(type, nexttype) %>%      mutate(key = if_else(type == nexttype & !is.na(type) & !is.na(nexttype), type, "other"),             val = 1) %>%      spread(key, val, fill = 0) %>%      select(-other)  #  type nexttype b c #1           1 0 0 #2           b 0 0 0 #3    b        b 0 1 0 #4    b        c 0 0 0 #5    c        c 0 0 1 #6    c     <na> 0 0 0 

data:

dat = data.frame(type = c("a","a","b","b","c","c"), nexttype = c("a", "b","b", "c","c",na), = c(rep(0,6)), b = rep(0,6), c = rep(0,6) , stringsasfactors = f)