group_by 并总结没有错误的丢弃值

Question

I am using group_by and summarise to compute the sum of a column by a location variable in another column. The dataframe is formatted as follows:

Store  Sales
AB12   12
BD43   32
DC65   65
AB12   1
DC65   3
DC65   4

store_total <- store %>%
group_by(store) %>%
summarise(total_sales = sum(total_sales))

When I run this code, I get the results for AB12 and the rest are NA values. Is there something wrong with the code or should I be using a different function?

Answer 1

I use Microsoft R Open v 4.0

Take a look at my answer:

Loading library:

library(dplyr)

Reproducing your dataframe:

store = c("AB12",   12,
"BD43",   32,
"DC65",   65,
"AB12",   1,
"DC65",   3,
"DC65",   4)

store<-as.data.frame(matrix(store, ncol=2, byrow=T))
names(store)<-c("Store",  "Sales")
store$Store<-as.factor(store$Store)
store$Sales<-as.numeric(store$Sales)
store


> store
  Store Sales
1  AB12    12
2  BD43    32
3  DC65    65
4  AB12     1
5  DC65     3
6  DC65     4

Fixing group_by parameter ( Store instead of store ) and summarise ( Sales instead of total_sales )

store_total <- store %>%
    group_by(Store) %>%
    summarise(total_sales = sum(Sales))

To be honest I don't like tibbles that's why I go back to a normal dataframe.

This is the final result:

store_total <- as.data.frame(store_total)
store_total

> store_total
  Store total_sales
1  AB12          13
2  BD43          32
3  DC65          72