Calculate final dates in time series created on general steps

Four functions for changing from time steps into dates. In general dates management for time series

The zip files contains four files for date management on a time series created based on general steps. It was a quite useful in my PhD for time series. The scripts allow for finding a final date in a time series knowing only the initial date and the number of days. Also for creating a list of date format and finding the number of days between two dates.