Question

关注此问题R: from a vector, list all subsets of elements so their sum just passes a value

我试图找到一种方法来将print命令给出的值存储在矢量或矩阵中，但我找不到任何方法。代码是：

v<-c(1,2,3)
threshold <- 3 # My threshold value

recursive.subset <-function(x, index, current, threshold, result){
  for (i in index:length(x)){
    if (current + x[i] >= threshold){
      print(sum(c(result,x[i]))) 
    } else {
      recursive.subset(x, i + 1, current+x[i], threshold, c(result,x[i]))
    }
  }
}

非常感谢提前。

我尝试了这段代码，但我得到了最后一笔费用

recursive.subset <-function(x, index, current, threshold, result){
  for (i in index:length(x)){
    if (current + x[i] >= threshold){
      return(sum(c(result,x[i]))) 
    } else {
      m<-recursive.subset(x, i + 1, current+x[i], threshold, c(result,x[i]))
    c(m,m)
    }
  }
 }

感谢

Answer 1

试试这个：

v<-c(1,2,3)
threshold <- 3 # My threshold value


recursive.subset <-function(x, index, current, threshold, result){
  for (i in index:length(x)){
    if (current + x[i] >= threshold){
      store <<- append(store, sum(c(result,x[i])))
    } else {
      recursive.subset(x, i + 1, current+x[i], threshold, c(result,x[i]))
    }
  }
}

store <- list()
inivector <- vector(mode="numeric", length=0) #initializing empty vector    
recursive.subset (v, 1, 0, threshold, inivector)

Answer 2

您的解决方案中的问题是“返回”声明的位置。解决方案可能是：

recursive.subset2 <-function(x, index, current, threshold, result){
  m <- NULL
  for (i in index:length(x)){
    if (current + x[i] >= threshold){
      m <- c(m, sum(c(result,x[i]))) 
    } else {
      m <- c(m, recursive.subset2(x, i + 1, current+x[i], threshold, c(result,x[i])))
    }
  }
  return(m)
 }

如何在具有嵌套函数的向量中存储值

2 个答案: