Get the date origin an xlsx file is using

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

convertToDate

Author

Alexander Walker

Examples

## create a file with some dates
if (FALSE) {
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)
}