我问这个问题是因为，作为 R 的新手，我很好奇为什么我写的一段代码可以正常工作，然后同一行代码在下次运行时会产生错误。
这是我正在使用的表的示例。
输入：
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 | 8L, 8L, 8L, 8L, 8L, 8L, 3L, 4L, 4L, 8L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 8L, 8L, 8L, 8L, 8L, 8L, 4L, 8L, 8L, 8L, 3L, 8L, 8L, 8L, 12L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 8L, 3L, 3L, 3L, 4L, 4L, 4L, 4L, 4L, 3L, 4L, 3L, 6L, 3L, 4L, 4L, 3L, 3L, 6L, 6L, 3L, 3L, 3L, 3L, 3L, 3L, 6L, 3L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 8L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 1L, 4L, 3L, 3L, 3L, 4L, 3L, 3L, 3L, 3L, 4L, 4L, 4L, 3L, 4L, 8L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 3L, 12L, 12L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 13L, 4L, 4L, 4L, 6L, 4L, 3L, 12L, 14L, 6L, 3L, 3L, 4L, 4L, 10L, 4L, 3L, 3L, 3L, 3L, 10L, 4L, 4L, 4L, 4L, 12L, 4L, 4L, 3L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 3L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 3L, 3L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 6L, 5L, 4L, 10L, 12L, 4L, 4L, 3L, 6L, 4L, 3L, 4L), .Label = c("coustani","demeilloni","funestus","gambiae", "garnhami","indetermine","marshallii","pharoensis","pretoriensis", "rufipes","salbaii","squamosus","tenebrosus","ziemani"), class ="factor"), Vila = c("Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Motaze","Motaze","Motaze", "Motaze","Motaze","Motaze","Chicutso","Chicutso","Chicutso", "Chicutso","Chicutso","Chicutso","Chicutso","Chicutso", "Chicutso","Chicutso","Chicutso","Chicutso","Chicutso", "Chicutso","Chicutso","Chicutso","Chicutso","Chicutso", "Chicutso","Chicutso","Chicutso","Chicutso","Chicutso", "Chicutso","Chicutso","Chicutso","Chicutso","Chicutso", "Chicutso","Chicutso","Chicutso","Chicutso","Chicutso", "Chicutso","Chicutso","Chicutso","Chicutso","Chicutso", "Chicutso","Chicutso","Chicutso","Chicutso","Chicutso", "Chicutso","Chicutso","Chicutso","Chicutso","Chicutso", "Chicutso","Chicutso","Chicutso","Chicutso","Chicutso", "Chicutso","Chicutso","Chicutso","Chicutso","Chicutso", "Chicutso","Chicutso","Chicutso","Chicutso","Chicutso", "Chicutso","Chicutso","Panjane","Panjane","Panjane", "Panjane","Panjane","Panjane","Panjane","Panjane","Panjane", "Panjane","Panjane","Panjane","Panjane","Panjane","Magude", "Magude","Magude","Magude","Magude","Magude","Magude", "Magude","Magude","Magude","Magude","Magude","Magude", "Magude", NA, NA,"Muginge","Muginge","Muginge","Muginge", "Muginge","Muginge","Muginge","Muginge","Muginge","Muginge", "Muginge","Muginge","Muginge","Muginge","Muginge","Muginge", "Muginge","Muginge","Muginge","Muginge","Muginge","Muginge", "Muginge","Muginge","Muginge","Muginge","Muginge","Muginge", "Muginge","Muginge","Muginge","Muginge","Muginge","Muginge", "Muginge","Muginge","Muginge","Muginge","Muginge","Muginge", "Muginge","Muginge","Muginge","Muginge","Muginge","Muginge", "Muginge","Muginge","Muginge","Muginge","Muginge","Muginge", "Muginge","Muginge","Muginge","Muginge","Muginge","Muginge", "Muginge","Muginge","Muginge","Muginge","Muginge","Muginge", "Muginge","Muginge","Muginge","Muginge","Muginge","Muginge", "Muginge","Muginge","Muginge","Muginge","Muginge","Muginge", "Muginge","Muginge","Muginge","Muginge", NA, NA,"Muginge", "Muginge","Muginge","Muginge","Muginge","Muginge","Muginge", "Muginge","Muginge","Muginge","Mapulanguene","Mapulanguene", "Mapulanguene","Mapulanguene","Mapulanguene","Mapulanguene", "Mapulanguene","Mapulanguene","Mapulanguene","Mapulanguene", "Mapulanguene","Mapulanguene")), class = c("tbl_df","tbl", "data.frame"), row.names = c(NA, -321L), .Names = c("a5species", "Vila")) |
我用这个代码来组织 Vila 的物种：
使用此代码生成了我想要的表，但下次我尝试运行代码时它停止工作并产生错误：
2 | object 'Vila' not found |
我意识到这与此处发布的问题类似：
如果在使用 data.table dplyr
时在函数中定义，则找不到 R 对象
但我正在使用 dplyr_0.4.3，这个问题表明他们遇到的问题现在已经解决了，而且我的代码也确实在某个时候工作过。此外，关于这篇文章的讨论非常技术性，它超出了我的想象。
知道为什么我的代码突然停止工作了吗？
谢谢。
这发生在我们从带有
2 3 4 | group_by(Vila) %>% filter(a5species=="gambiae") %>% summarise(n=n()) |
OP的代码
2 | ^^ ^^ |
Error in group_by_(.data, .dots = lazyeval::lazy_dots(...), add = add)
: object 'Vila' not found
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