传播行的重复标识符

Question

已经有关于这个主题的问题之前这儿,但我仍然有传播这种挣扎.我希望每个state人都有自己的温度值列.

这是dput()我的一个数据.我会叫它df

structure(list(date = c("2018-01-21", "2018-01-21", "2018-01-20", 
"2018-01-20", "2018-01-19", "2018-01-19", "2018-01-18", "2018-01-18", 
"2018-01-17", "2018-01-17", "2018-01-16", "2018-01-16", "2018-01-15", 
"2018-01-15", "2018-01-14", "2018-01-14", "2018-01-12", "2018-01-12", 
"2018-01-11", "2018-01-11", "2018-01-10", "2018-01-10", "2018-01-09", 
"2018-01-09", "2018-01-08", "2018-01-08", "2018-01-07", "2018-01-07", 
"2018-01-06", "2018-01-06", "2018-01-05", "2018-01-05", "2018-01-04", 
"2018-01-04", "2018-01-03", "2018-01-03", "2018-01-03", "2018-01-03", 
"2018-01-02", "2018-01-02"), tmin = c(24, 31, 31, 29, 44, 17, 
32, 7, 31, 7, 31, 6, 30, 13, 30, 1, 43, 20, 33, 52, 42, 29, 30, 
29, 26, 32, 33, -2, 29, 0, 23, 3, 19, 11, NA, -3, 22, -3, 24, 
-4), state = c("UT", "OH", "UT", "OH", "UT", "OH", "UT", "OH", 
"UT", "OH", "UT", "OH", "UT", "OH", "UT", "OH", "UT", "OH", "UT", 
"OH", "UT", "OH", "UT", "OH", "UT", "OH", "UT", "OH", "UT", "OH", 
"UT", "OH", "UT", "OH", "UT", "OH", "UT", "OH", "UT", "OH")), class = "data.frame", row.names = c(NA, 
-40L), .Names = c("date", "tmin", "state"))

我运行的代码是

df %>% spread(state,tmin)

我期望给我以下格式

date UT  OH
... ... ...

但我收到错误信息

错误:行的重复标识符(36,38),(35,37)

我尝试了一些不同的东西.我试过的一件事是按日期分组.我当时认为同一天的行导致了问题spread.我还尝试使用add_rownames()然后使用新行spread(state,tmin),但这也未能解决问题.

Answer 1

为了spread按预期工作,结果数据框必须具有唯一标识的行和列.对于您的数据,"日期"列是传播后唯一的唯一标识符.但是,第36行和第38行是相同的:

         date tmin state
36 2018-01-03   -3    OH
38 2018-01-03   -3    OH

这使得tidyr处于尝试将两个数据点解析为同一行和列的不可能的位置.此外,第35行和第37行都具有相同的日期和状态,再次创建了将两个不同值放入新数据框中相同位置的不可能情况:

         date tmin state
35 2018-01-03   NA    UT
37 2018-01-03   22    UT

以下数据清理将使传播成为可能:

df %>% 
  filter(!is.na(tmin)) %>% # remove NA values
  unique %>% # remove duplicated rows
  spread(state, tmin)

         date OH UT
1  2018-01-02 -4 24
2  2018-01-03 -3 22
3  2018-01-04 11 19
4  2018-01-05  3 23
5  2018-01-06  0 29
...