Return the date origin used internally by an xlsx or xlsm file

getDateOrigin(xlsxFile)

Arguments

xlsxFile

An xlsx or xlsm file.

Value

One of "1900-01-01" or "1904-01-01".

Details

Excel stores dates as the number of days from either 1904-01-01 or 1900-01-01. This function checks the date origin being used in an Excel file and returns is so it can be used in convertToDate()

See also

Author

Alexander Walker

Examples


## create a file with some dates
if (FALSE) { # \dontrun{
write.xlsx(as.Date("2015-01-10") - (0:4), file = "getDateOriginExample.xlsx")
m <- read.xlsx("getDateOriginExample.xlsx")

## convert to dates
do <- getDateOrigin(system.file("extdata", "readTest.xlsx", package = "openxlsx"))
convertToDate(m[[1]], do)
} # }