# Checks if a date/time vector is regular

`calendar-isRegular.Rd`

Checks if a date/time vector is regular. i.e. if it is a daily, a monthly, or a quarterly date/time vector. If the date/time vector is regular the frequency can determined calling the function frequency.

## Usage

```
# S4 method for timeDate
isDaily(x)
# S4 method for timeDate
isMonthly(x)
# S4 method for timeDate
isQuarterly(x)
# S4 method for timeDate
isRegular(x)
# S4 method for timeDate
frequency(x, ...)
```

## Details

A date/time vector is defined as daily if the vector has not more than one date/time stamp per day.

A date/time vector is defined as monthly if the vector has not more than one date/time stamp per month.

A date/time vector is defined as quarterly if the vector has not more than one date/time stamp per quarter.

A monthly date/time vector is also a daily vector, a quarterly date/time vector is also a monthly vector.

A regular date/time vector is either a monthly or a quarterly vector.

NOT yet implemented is the case of weekly vectors.