r - 使用 spread 使用 tidyr 创建两个值列

Question

我有一个看起来像这样的数据框(见链接)。我想采用下面产生的输出，并通过将色调变量扩展到 n 和平均变量来更进一步。似乎这个主题可能与此有关，但我无法让它发挥作用:
Is it possible to use spread on multiple columns in tidyr similar to dcast?

我希望最终表格将源变量放在一列中，然后将tone-n 和tone-avg 变量放在列中。所以我希望列标题是“源” - “For - n” - “Against - n” “For -Avg” - “Against - Avg”。这是为了发表，不是为了进一步计算，所以它是关于呈现数据的。以这种方式呈现数据对我来说似乎更直观。谢谢你。

#variable1
Politician.For<-sample(seq(0,4,1),50, replace=TRUE)
#variable2
Politician.Against<-sample(seq(0,4,1),50, replace=TRUE)
#Variable3
Activist.For<-sample(seq(0,4,1),50,replace=TRUE)
#variable4
Activist.Against<-sample(seq(0,4,1),50,replace=TRUE)
#dataframe
df<-data.frame(Politician.For, Politician.Against, Activist.For,Activist.Against)

#tidyr
df %>%
 #Gather all columns 
 gather(df) %>%
 #separate by the period character 
 #(default separation character is non-alpha numeric characterr) 
 separate(col=df, into=c('source', 'tone')) %>%
 #group by both source and tone  
 group_by(source,tone) %>%
 #summarise to create counts and average
 summarise(n=sum(value), avg=mean(value)) %>%
 #try to spread
 spread(tone, c('n', 'value'))

Answer 1

我认为你想要的是另一个聚集来将计数和平均值作为单独的观察结果，gather(type, val, -source, -tone)以下。

gather(df, who, value) %>%
    separate(who, into=c('source', 'tone')) %>%
    group_by(source, tone) %>%
    summarise(n=sum(value), avg=mean(value)) %>%
    gather(type, val, -source, -tone) %>%
    unite(stat, c(tone, type)) %>%
    spread(stat, val)

产量

Source: local data frame [2 x 5]

      source Against_avg Against_n For_avg For_n
1   Activist        1.82        91    1.84    92
2 Politician        1.94        97    1.70    85