R / openxlsx /在Excel文件中查找第一个非空单元格

Question

I'm trying to write data to an existing Excel file from R, while preserving the formatting. I'm able to do so following the answer to this question ( Write from R into template in excel while preserving formatting ), except that my file includes empty columns at the beginning, and so I cannot just begin to write data at cell A1.

As a solution I was hoping to be able to find the first non-empty cell, then start writing from there. If I run read.xlsx(file="myfile.xlsx") using the openxlsx package, the empty columns and rows are automatically removed, and only the data is left, so this doesn't work for me.

So I thought I would first load the worksheet using wb <- loadWorkbook("file.xlsx") so I have access to getStyles(wb) (which works). However, the subsequent command getTables returns character(0) , and wb$tables returns NULL . I can't figure out why this is? Am I right in that these variables would tell me the first non-empty cell?

I've tried manually removing the empty columns and rows preceding the data, straight in the Excel file, but that doesn't change things. Am I on the right path here or is there a different solution?

Answer 1

As suggested by Stéphane Laurent , the package tidyxl offers the perfect solution here.

For instance, I can now search the Excel file for a character value, like my variable names of interest ("Item", "Score", and "Mean", which correspond to the names() of the data.frame I want to write to my Excel file):

require(tidyxl)
colnames <- c("Item","Score","Mean")
excelfile <- "FormattedSheet.xlsx"
x <- xlsx_cells(excelfile)

  # Find all cells with character values: return their address (i.e., Cell) and character (i.e., Value)
  chars <- x[x$data_type == "character", c("address", "character")]

  starting.positions <- unlist(
    chars[which(chars$character %in% colnames), "address"]
  )
     # returns: c(C6, D6, E6)