This function is to transform a period of time in date to millisecond according to the origin date and the format of date.
dateTOmillisecond(date, origin = "1970-01-01", format = "%Y-%m-%d",
interval = TRUE)A character vector represent a period of time from date[1] to date[2].
A point of time which set to be zero in millisecond.
A format for date and origin arguments.
A logical argument which equals to TRUE by default when the function transfer an period of dates to millisecond. When interval=FALSE, the function returns the last minute of every elements of date to millisecons.
A vector of size two represent a period of time. The start date of the period will be transform to the first millisecond of the date and the end of the period to the last millisecond.