openxlsx::write.xlsx 改写现有工作表 append

Question

The openxlsx::write.xlsx function is overwriting spreadsheet instead of adding another tab.

I tried do follow some orientations of Stackoverflow, but without sucess.

dt.escrita <- format(Sys.time(), '%Y%m%d%H%M%S')

write.xlsx( tbl.messages
           ,file = paste('.\\2_Datasets\\messages_',dt.escrita,'.xlsx')
           ,sheetName = format(Sys.time(), '%d-%m-%y')
           ,append = FALSE)

write.xlsx( tbl.dic.dados
            ,file = paste('.\\2_Datasets\\messages_',dt.escrita,'.xlsx')
            ,sheetName = 'Dicionario_Dados'
            ,append = TRUE)

A spreadsheet with two tabs named: 30-07-19 and Dicionario_Dados.

Answer 1

Not sure if I understand correctly, you want to create one xlsx file with two tabs/sheets? Then I usually first create the sheets and then write into each sheet seperatly (This is different from adding data to the same sheet by appending it).

library("openxlsx")
mtcars1 <- mtcars %>% filter(cyl == 4)
mtcars2 <- mtcars %>% filter(cyl == 6)

wb <- createWorkbook()
addWorksheet(wb, "mtcars1")
addWorksheet(wb, "mtcars2")

writeData(wb, "mtcars1", mtcars1, startRow = 1, startCol = 1)
writeData(wb, "mtcars2", mtcars2, startRow = 1, startCol = 1)

saveWorkbook(wb, file = "excel_test.xlsx", overwrite = TRUE)

: Just wondering why I never used the append argument in openxlsx (which is my standard package for read/writing excel). It seems like there is no such argument to neither of the three functions write.xlsx() , writeData() , writeDataTable() . At least it's not in the documentation.

The function does not seem to throw an error when called with unknown arguments, for example the call below has a non-existing somearg , but returns no error.

write.xlsx(mtcars2,
           file = "excel_test.xlsx",
           sheetName = "mtcars1",
           somearg = TRUE)

To append data to an existing table you could read in the number of rows of the existing worksheet, add +1 and use this values as startRow:

wb2 <- loadWorkbook(file = "excel_test.xlsx")

writeData(wb2,
          "mtcars1",
          mtcars2,
          colNames = FALSE,
          startRow = nrow(readWorkbook("excel_test.xlsx"))+1)
#Fixed the call to nrow, instead of ncol.

saveWorkbook(wb2, file = "excel_test.xlsx", overwrite = TRUE)

Answer 2

Write different dataframes to different sheets.

library(xlsx)
write.xlsx(dataframe1, file="filename.xlsx", sheetName="sheet1")
write.xlsx(dataframe2, file="filename.xlsx", sheetName="sheet2", append=TRUE)

Answer 3

You can simply use a named list of dataframes:

library(openxlsx)

df_lst <- setNames(list(tbl.messages, tbl.dic.dados), as.list(c(format(Sys.time(), '%d-%m-%y'), 'Dicionario_Dados')))

write.xlsx( df_lst, file = paste0('.\\2_Datasets\\messages_',dt.escrita,'.xlsx') )

Answer 4

The write.xlsx function of the xlsx package does have an append argument