我有一张这样的 table ，
> head(dt2)
Weight Height Fitted interval limit value
1 65.6 174.0 71.91200 pred lwr 53.73165
2 80.7 193.5 91.63237 pred lwr 73.33198
3 72.6 186.5 84.55326 pred lwr 66.31751
4 78.8 187.2 85.26117 pred lwr 67.02004
5 74.8 181.5 79.49675 pred lwr 61.29244
6 86.4 184.0 82.02501 pred lwr 63.80652
我希望它有这样的，
> head(reshape2::dcast(dt2,
Weight + Height + Fitted + interval ~ limit,
fun.aggregate = mean))
Weight Height Fitted interval lwr upr
1 42.0 153.4 51.07920 conf 49.15463 53.00376
2 42.0 153.4 51.07920 pred 32.82122 69.33717
3 43.2 160.0 57.75378 conf 56.35240 59.15516
4 43.2 160.0 57.75378 pred 39.54352 75.96404
5 44.8 149.5 47.13512 conf 44.87642 49.39382
6 44.8 149.5 47.13512 pred 28.83891 65.43133
但是使用
tidyr::spread ， 我怎样才能做到这一点？我正在使用，
> tidyr::spread(dt2, limit, value)
但得到错误，
Error: Duplicate identifiers for rows (1052, 1056), (238, 242), (1209, 1218), (395, 404), (839, 1170), (25, 356), (1173, 1203, 1215), (359, 389, 401), (1001, 1200), (187, 386), (906, 907), (92, 93), (930, 1144), (116, 330), (958, 1171), (144, 357), (902, 1018), (88, 204), (960, 1008), (146, 194), (1459, 1463), (645, 649), (1616, 1625), (802, 811), (1246, 1577), (432, 763), (1580, 1610, 1622), (766, 796, 808), (1408, 1607), (594, 793), (1313, 1314), (499, 500), (1337, 1551), (523, 737), (1365, 1578), (551, 764), (1309, 1425), (495, 611), (1367, 1415), (553, 601)
随机 10 行::
> dt[sample(nrow(dt), 10), ]
Weight Height Fitted interval limit value
1253 52.2 162.5 60.28203 conf upr 61.51087
426 49.1 158.8 56.54022 pred upr 74.75756
1117 78.4 184.5 82.53066 conf lwr 80.98778
1171 85.9 166.4 64.22611 conf lwr 63.21254
948 61.4 177.8 75.75494 conf lwr 74.66393
384 90.9 172.7 70.59731 pred lwr 52.41828
289 75.9 172.7 70.59731 pred lwr 52.41828
3 44.8 149.5 47.13512 pred lwr 28.83891
774 87.3 182.9 80.91258 pred upr 99.12445
772 86.4 175.3 73.22669 pred upr 91.40919
最佳答案
假设您从如下所示的数据开始:
mydf
# Weight Height Fitted interval limit value
# 1 42 153.4 51.0792 conf lwr 49.15463
# 2 42 153.4 51.0792 pred lwr 32.82122
# 3 42 153.4 51.0792 conf upr 53.00376
# 4 42 153.4 51.0792 pred upr 69.33717
# 5 42 153.4 51.0792 conf lwr 60.00000
# 6 42 153.4 51.0792 pred lwr 90.00000
请注意分组列(1 到 5)的第 5 行和第 6 行中的重复项。这基本上就是“tidyr”告诉你的。第一行和第五行是重复的，第二行和第六行也是如此。
tidyr::spread(mydf, limit, value)
# Error: Duplicate identifiers for rows (1, 5), (2, 6)
正如@Jaap 所建议的，解决方案是首先“总结”数据。由于“tidyr”仅用于整形数据(与聚合和整形的“reshape2”不同)，您需要在更改数据形式之前使用“dplyr”执行聚合。在这里，我用
summarise 做到了。对于“值”列。如果您在
summarise 处停止执行一步，你会发现我们原来的 6 行数据集已经“缩小”到 4 行。现在，spread会按预期工作。mydf %>%
group_by(Weight, Height, Fitted, interval, limit) %>%
summarise(value = mean(value)) %>%
spread(limit, value)
# Source: local data frame [2 x 6]
#
# Weight Height Fitted interval lwr upr
# (dbl) (dbl) (dbl) (chr) (dbl) (dbl)
# 1 42 153.4 51.0792 conf 54.57731 53.00376
# 2 42 153.4 51.0792 pred 61.41061 69.33717
这与
dcast 的预期输出相匹配与 fun.aggregate = mean .reshape2::dcast(mydf, Weight + Height + Fitted + interval ~ limit, fun.aggregate = mean)
# Weight Height Fitted interval lwr upr
# 1 42 153.4 51.0792 conf 54.57731 53.00376
# 2 42 153.4 51.0792 pred 61.41061 69.33717
样本数据:
mydf <- structure(list(Weight = c(42, 42, 42, 42, 42, 42), Height = c(153.4,
153.4, 153.4, 153.4, 153.4, 153.4), Fitted = c(51.0792, 51.0792,
51.0792, 51.0792, 51.0792, 51.0792), interval = c("conf", "pred",
"conf", "pred", "conf", "pred"), limit = structure(c(1L, 1L,
2L, 2L, 1L, 1L), .Label = c("lwr", "upr"), class = "factor"),
value = c(49.15463, 32.82122, 53.00376, 69.33717, 60,
90)), .Names = c("Weight", "Height", "Fitted", "interval",
"limit", "value"), row.names = c(NA, 6L), class = "data.frame")
关于r - 传播与 dcast，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/35225052/