adjust_periodDF         Function to adjust starts and ends for periods
                        in periodDF object
as.data.frame.timeDF    Convert timeDF object to a plain dataframe
as.periodDF             Function to construct periodDF object from
                        dataframe
as.timeDF               Function to construct timeDF object from
                        dataframe
condense_periodDF       Function to condense periods in periodDF object
convert_periodDF        Function to convert type of periodDF object
extract_with_periodDF   Extract time records from timeDF object within
                        periods of periodDF object
flag_with_periodDF      Flag time records from timeDF object within
                        periods of periodDF object
listTimeDF_to_timeDF    converts a list of timeDF objects into a timeDF
                        object
periodDF-class          periodDF S3 class
period_type             Function to obtain period type of periodDF
                        object
select_timeDF           Function to select columns in timeDF object
sort_periodDF           Function to sort periods in periodDF object
sort_timeDF             Function to sort records in timeDF object
split_timeDF_by_intervals
                        Function to split timeDF into a list by regular
                        intervals
summary.periodDF        Summarize periodDF S3 object
summary.timeDF          Summarize timeDF S3 object
timeDF-class            timeDF S3 class
timeDF-package          Subset and Flag Data Frames with Times by the
                        Use of Periods
time_vec                time vector and column name for times of timeDF
validate_listTimeDF     Checks whether the object is a list of timeDF
                        objects
validate_sorted_timeDF
                        Checks whether the object is a valid sorted
                        timeDF object
validate_timeDF         Checks whether the object is a valid timeDF
                        object
vec_to_periodDF         Function to construct periodDF object from
                        vector
