R Extract Data Frame from List Without Prefixes in Column Names
I Place a Data Frame Inside the List. Then When Try to Extract It Back - I Get All Column Names Prefixed with List Key for This Data Frame, Is There a Way to...
I place a data frame inside the list. Then when try to extract it back - I get all column names prefixed with list key for this data frame, is there a way to extract data frame exactly as it was passed initially?
cols<-c("column1", "Column2", "Column3")
df1<-data.frame(matrix(ncol = 3, nrow = 1))
colnames(df1)<-cols
df1
result<-list()
result['df1']<-list(df1)
newdf1<-as.data.frame(result['df1'])
newdf1
Get as a result (column names are prefixed with df1):
> cols<-c("column1", "Column2", "Column3")
> df1<-data.frame(matrix(ncol = 3, nrow = 1))
> colnames(df1)<-cols
> df1
column1 Column2 Column3
1 NA NA NA
>
> result<-list()
> result['df1']<-list(df1)
>
> newdf1<-as.data.frame(result['df1'])
> newdf1
df1.column1 df1.Column2 df1.Column3
1 NA NA NA
Of course, I can remove the prefixes manually, but probably there is a proper way to do this. Thanks!
1 Answer
Extract using [[ rather than [:
> newdf1 <- as.data.frame(result[['df1']])
> newdf1
column1 Column2 Column3
1 NA NA NA
The difference is that [ extracts a list containing the requested component(s). [[ extracts the requested component directly (i.e. it retrieves the contents of that component of the list, not a list containing that component).
But as df1 already is a data frame, why not just do:
newdf1 <- result[['df1']]
? You don't need the as.data.frame() part.
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