f.multi.weekly {tdata}

Create a Multi-Week Frequency

Description

Use this function to create a frequency for time-series data that occurs every 'k' weeks. The first day of the first week is used as the reference.

Usage

f.multi.weekly(date, k)

Arguments

date

The date, which can be a list with year, month, and day elements. It can also be an integer array with 3 elements for year, month, and day respectively, or an object that can be used as an argument for the base::as.Date function.

k

The number of weeks.

Details

To use the as.frequency function for this type of frequency, you need the following information:

• Character Format The first day of the first week in "YYYYMMDD" format.

• Class Id "w#" (the number is the value of k; e.g., w3 means every 3 weeks)

Value

An object of class ldtf, which is also a list with the following members:

class

The class of this frequency.

year

The year.

month

The month.

day

The day.

k

The value of k.

Examples

mw0 <- f.multi.weekly(c(2023, 1, 2), 3)
# This is 2/1/2023, which is Monday. The next observation belongs to 23/1/2023.

mw0_value_str <- as.character(mw0) # This will be '20230102'.
mw0_class_str <- get.class.id(mw0) # This will be 'w3'.

mw_new <- as.frequency("20230109", "w4") # This is 9/1/2023.

# Don't use invalid or unsupported dates:

mw_invalid <- try(as.frequency("1399109", "w4")) # this is a too old date and unsupported
mw_invalid <- try(as.frequency("20230132", "w5")) # invalid day in month
mw_invalid <- try(as.frequency("20231331", "w2")) # invalid month
mw_invalid <- try(as.frequency("20231012", "w0"))