dplyr 单独返回错误

Question

尝试将结果列从 df2 分成 2 个单独的列（"Winner"、"Loser" 并使用以下代码从每个新列中删除数字，但收到以下错误消息。发生了什么变化需要改正吗？

df2 <- data.frame(Year = c(2015:1903 ), Results = c("Winner", "Loser"))
df2 %>% separate(type, c("Winner", "Loser"), ",")

Error in if (!after) c(values, x) else if (after >= lengx) c(x, values) else c(x[1L:after],  :
argument is of length zero

df2

    Year                              Results                 MVP
1   2015                          Royals 4, Mets 1      Salvador Perez
2   2014                        Giants 4, Royals 3   Madison Bumgarner
3   2013                    Red Sox 4, Cardinals 2         David Ortiz
4   2012                        Giants 4, Tigers 0      Pablo Sandoval
5   2011                    Cardinals 4, Rangers 3        David Freese
.
.
125 1906       Chicago White Sox 4, Chicago Cubs 2                  --
126 1905           NY Giants 4, Philadelphia A's 1                  --
128 1903            Boston Red Sox 5, Pittsburgh 3                  --

Answer 1

这是 separate() 的一种解决方案。在您的代码中，separate() 中有 type。您可能需要仔细检查一下。在这里，我创建了一个名为 df2 的示例数据框并执行了以下操作。首先，我删除了 space 和 Results 中的数字。然后，我使用 separate().

分隔列

library(dplyr)
library(tidyr)

mutate(df2, Results = gsub(pattern = "\s|\d+", replacement = "", x = Results)) %>%
separate(col = "Results", into = c("Winner", "Loser"), sep = ",")

#  Year    Winner     Loser
#1 2000    Royals      Mets
#2 2001    Giants    Royals
#3 2002    RedSox Cardinals
#4 2003    Giants    Tigers
#5 2004 Cardinals   Rangers

数据

df2 <- structure(list(Year = 2000:2004, Results = c("Royals 4, Mets 1", 
"Giants 4, Royals 3", "Red Sox 4, Cardinals 2", "Giants 4, Tigers 0", 
"Cardinals 4, Rangers 3")), .Names = c("Year", "Results"), row.names = c(NA, 
-5L), class = "data.frame")

#  Year                Results
#1 2000       Royals 4, Mets 1
#2 2001     Giants 4, Royals 3
#3 2002 Red Sox 4, Cardinals 2
#4 2003     Giants 4, Tigers 0
#5 2004 Cardinals 4, Rangers 3

Answer 2

您也可以通过使用 tidyr::extract（使用@jazzurros 数据）

的单个调用来完成此操作

extract(df2, 
        "Results", c("Winner", "Loser"), 
        "([[:alpha:] ]+)\s+\d+,\s+([[:alpha:] ]+)\s+\d+")
#   Year    Winner     Loser
# 1 2000    Royals      Mets
# 2 2001    Giants    Royals
# 3 2002   Red Sox Cardinals
# 4 2003    Giants    Tigers
# 5 2004 Cardinals   Rangers

dplyr 单独返回错误

dplyr separate returning error

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