[R] automatic convert list to dataframe

Rui Barradas ru|pb@rr@d@@ @end|ng |rom @@po@pt
Mon Oct 3 21:08:57 CEST 2022


Hello,

If in each iteration i is a list, try removing the call to names().
Try, in the loop,


list2env(i, envir = .GlobalEnv)


The error message is telling that list2env's first argument must be a 
named list and names(i) is an unnamed vector, it's i that's the named 
list (you even changed its names in the previous instruction).

Hope this helps,

Rui Barradas

Às 18:38 de 03/10/2022, Kai Yang escreveu:
>   Hi Rui,
> list2env(file1, envir = .GlobalEnv) is worked very well. Thank you.
> 
> But when I tried to put the sample code  into for loop. I got error message:
> for(i in filenames){
>    assign(i, import_list(paste0(i, ".xlsx", sep="")))
>    names(i) <- paste(i, names(i), sep = "_")
>    list2env(names(i), envir = .GlobalEnv)
> }
> Error in list2env(names(i), envir = .GlobalEnv) :   first argument must be a named list
> 
> It seems I cannot put names(i) into for loop, Could you please help me to debug it?
> Thank you,Kai    On Monday, October 3, 2022 at 10:14:25 AM PDT, Rui Barradas <ruipbarradas using sapo.pt> wrote:
>   
>   Hello,
> 
> 
> list2env(file1, envir = .GlobalEnv)
> 
> 
> will create data.frames dx1, dx2, etc, in the global environment.
> If you really need the names file1_dx1, file1_dx2, etc, you can first
> change the names
> 
> 
> names(file1) <- paste("file1", names(file1), sep = "_")
> 
> 
> and then run list2env like above.
> 
> Hope this helps,
> 
> Rui Barradas
> 
> Às 16:51 de 03/10/2022, Kai Yang via R-help escreveu:
>> Hi R team,
>> I can use rio package to read excel file into R as a list. The excel file content multiple sheets (30 - 40 data sheets). I can convert each data elements into dataframe manually. I have multiple excel files with multiple data sheets. I need to load them into R and do the comparison for same sheet name from difference excel file. My current code is:
>>    library(rio)   setwd ("C:/temp")
>> filenames <- gsub("\\.xlsx$","", list.files(pattern="\\.xlsx$"))
>> for(i in filenames){
>>      assign(i, import_list(paste0(i, ".xlsx", sep="")))
>> }
>> file1_dx1     <-  file1[["dx1"]]
>>
>> file1_dx2     <-  file1[["dx2"]]
>>
>> file1_dx3     <-  file1[["dx3"]]
>>
>> file2_dx1     <-  file1[["dx1"]]
>>
>> file2_dx2     <-  file1[["dx2"]]
>> ......
>>
>> I hope the code can automatic converting the list (may have 30 - 40 lists) by adding file name (such as: filename_sheetname) and put it in for loop
>>
>>
>> Thank you,
>> Kai
>>
>>
>>
>>
>>      [[alternative HTML version deleted]]
>>
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>



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