示例

#I have a vector containing a sequence of numbers, with some duplicates and gaps, 
#and I want to use its start and end points to create an analogous consecutive sequence.

original_sequence <- c(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 
13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 
28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 
43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 
58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 
73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,
88, 89, 90, 91, 92, 93, 94, 95, 96, 98, 98, 99, 100, 101, 
102, 103, 104, 105, 106, 107, 108, 109, 110)

## unsuccessful attempt #1
original_sequence %>%
   range() %>% 
   seq()
[1] 1 2 ## this result is equivalent to the output of `seq(2)`, 
        ## but what I want is to compute `seq(1 ,110)`.


## unsuccessful attempt #2
original_sequence %>%
   range() %>% 
   seq(.[1]), .[2])

Error: unexpected ',' in:
"    range() %>% 
    seq(.[1]),"

## attempt #3: somewhat successful but I wonder whether there's a better way
original_sequence %>%
   range() %>% 
   sapply(., seq)

[[1]]
[1] 1

[[2]]
  [1]   1   2   3   4   5   6   7   8   9  10  11  12  13  14  15  16  17  18  19  20  21  22  23  24  25  26  27  28  29  30  31  32  33  34  35  36  37  38
 [39]  39  40  41  42  43  44  45  46  47  48  49  50  51  52  53  54  55  56  57  58  59  60  61  62  63  64  65  66  67  68  69  70  71  72  73  74  75  76
 [77]  77  78  79  80  81  82  83  84  85  86  87  88  89  90  91  92  93  94  95  96  97  98  99 100 101 102 103 104 105 106 107 108 109 110

底线-我能够用sapply做到这一点，但我希望本着第二次尝试的精神找出解决方案，因为知道一种通用的方法来挑选具体的方法更为方便您要传递给下一个函数的参数的向量元素。

Answer 1

一种方法是使用{}并将输入参数传递给seq

library(dplyr)

original_sequence %>%
  range() %>% 
  {seq(.[[1]], .[2])}

#[1]  1  2  3  4  5  6  7  8  9 10  11  12......

或者我们可以将其与基数R do.call

混合使用

original_sequence %>% range() %>% {do.call(seq, as.list(.))}

或者如@ Ozan147所述，如果您的序列始终以1开头，我们可以使用max

original_sequence %>% max %>% seq

Answer 2

我们可以使用reduce

library(tidyverse)
original_sequence %>% 
    range %>%
    reduce(seq)
#[1]   1   2   3   4   ...

R中的管道::馈入下一个函数的参数时传递特定的矢量元素

示例

2 个答案: