如果接受另外 3 列中的条件，则在同一列的下一行中用 NA 替换值

Question

如果第 3 列的条件与上一行相同，我需要将同一列的下一行中的数据替换为 NA。这个条件的代码怎么写？

例如我有这样的示例数据

store camp  var    value
 a     1     ax     200
 b     2     bx     100
 a     1     ax     200
 b     2     bx     100
 c     2     cx     100
 a     1     ax     200
 c     2     cx     100

变成这样

store camp  var    value
 a     1     ax     200
 b     2     bx     100
 a     1     ax     NA
 b     2     bx     NA
 c     2     cx     100
 a     1     ax     NA
 c     2     cx     NA

有没有办法做到这一点？提前谢谢

Answer 1

您可以使用重复的 - 这与您拥有的相匹配

 x <- data.frame( 
 store = c( "a","b","a","b","c","a","c"),
 camp = c(1,2,1,2,2,1,2),
 var = c( "ax","bx","ax","bx","cx","ax","cx"),
 value = c( 200,100,200,100,100,200,10))

 x[ duplicated( x[ , c( "store","camp","var")]) ,"value"] <- NA

如果接受另外 3 列中的条件，则在同一列的下一行中用 NA 替换值

Replace value with NA in next row on the same column if condition in another 3 columns are accepted

r

replace

conditional