R中因子的总计数总和

I am very new to R and this is my first stack overflow question so I expect this may be a little rough. I have a data frame (from a .csv) in the following structure:

我是R的新手，这是我的第一个堆栈溢出问题所以我希望这可能有点粗糙。我在以下结构中有一个数据框（来自.csv）：

FeatureName     Uuid     Count 

ClickHeadline   ABC1     17 
ChangeSetting   ABC1     3  
ClickHeadline   CBA2     5 
ChangeSetting   CBA2     7 
SomethingElse   CBA2     5

I am trying to figure out how to make a new data frame in which the unique values of FeatureName, the factors ClickHeadline, ChangeSetting, SomethingElse are now variables summing over the Count for each Uuid. So the new data frame I want would be:

我试图弄清楚如何创建一个新的数据框，其中FeatureName的唯一值，因子ClickHeadline，ChangeSetting，SomethingElse现在是每个Uuid的Count的变量。所以我想要的新数据框将是：

Uuid    ClickHeadline    ChangeSetting    SomethingElse
ABC1    17               3                0
CBA2    5                7                5

I feel like I should be able to do this over the aggregate function, but I can't figure out how to tell it to look sum over the counts by a variable. I know I'm in way over my head but can anybody help me figure this out?

我觉得我应该能够在聚合函数上做到这一点，但是我无法弄清楚如何通过变量来判断它的总和。我知道我已经超越了我的头脑，但有人可以帮我解决这个问题吗？

1 个解决方案

#1

There are many possibilities

有很多种可能性

If you require a sum you could also use the reshape2 package dcast function

如果您需要总和，您还可以使用reshape2包dcast功能

df <- read.table(header=T, text='
                 FeatureName     Uuid     Count 

ClickHeadline   ABC1     17 
ChangeSetting   ABC1     3  
ClickHeadline   CBA2     5 
ChangeSetting   CBA2     7 
SomethingElse   CBA2     5
                 ')

library(reshape2)
dcast(df, Uuid ~ FeatureName, value.var="Count", sum)

  Uuid ChangeSetting ClickHeadline SomethingElse
1 ABC1             3            17             0
2 CBA2             7             5             5

If you dataset is limited to the scope you provided you just can use the base reshape function

如果数据集仅限于您提供的范围，则可以使用基本重塑功能

out <- reshape(df, idvar="Uuid", timevar="FeatureName", v.names="Count", direction="wide")
out[is.na(out)] = 0
out
  Uuid Count.ClickHeadline Count.ChangeSetting Count.SomethingElse
1 ABC1                  17                   3                   0
3 CBA2                   5                   7                   5

Another base R alternative is xtabs without need for removing NA

另一个基本R替代品是xtabs，无需移除NA

xtabs(Count ~ Uuid+FeatureName, df)
      FeatureName
Uuid   ChangeSetting ClickHeadline SomethingElse
  ABC1             3            17             0
  CBA2             7             5             5

tidyr package solution with spread

tidyr包装解决方案与传播

library(tidyr)
spread(df, key=FeatureName, value=Count, fill=0)
  Uuid ChangeSetting ClickHeadline SomethingElse
1 ABC1             3            17             0
2 CBA2             7             5             5

#1