interval_nature: Properties of a 'datey_interval'

In datey: Exact Date and Duration Arithmetic on an Annual Grid

Properties of a datey_interval

Description

Test whether intervals, [a,b), are 'proper' or 'collapsed':

• A proper interval does not end before its start, i.e. a \le b.

• A collapsed interval does not start before its end, i.e. a \ge b.

An NA interval is treated as collapsed and improper.

These definitions imply the following:

• A collapsed interval could be empty or improper.

• To test for an empty interval, i.e. [a,a), test that it is both proper and collapsed.

These methods are guaranteed to return TRUE or FALSE, i.e. not NA (provided the argument is an interval).

Vector versions mapping each element of x to TRUE or FALSE:

is_proper(x) tests whether the elements of x are proper. is_collapsed(x) tests whether the elements of x are collapsed.

Scalar versions mapping x to a scalar TRUE or FALSE:

all_proper(x) tests whether all the elements of x are proper. all_collapsed(x) tests whether all the elements of x are collapsed. any_collapsed(x) tests whether at least one of the elements of x is collapsed.

(any_proper() is not implemented because there is no obvious use case.)

These are S3 generic functions.

Usage

is_proper(x)

## Default S3 method:
is_proper(x)

## S3 method for class 'datey_interval'
is_proper(x)

all_proper(x)

## Default S3 method:
all_proper(x)

## S3 method for class 'datey_interval'
all_proper(x)

is_collapsed(x)

## Default S3 method:
is_collapsed(x)

## S3 method for class 'datey_interval'
is_collapsed(x)

all_collapsed(x)

## Default S3 method:
all_collapsed(x)

## S3 method for class 'datey_interval'
all_collapsed(x)

any_collapsed(x)

## Default S3 method:
any_collapsed(x)

## S3 method for class 'datey_interval'
any_collapsed(x)

Arguments

x	The interval to test.

Value

• is_XXX functions return a logical vector corresponding the property.

• all_XXX and any_XXX functions return a logical scalar.

See Also

datey_interval, interval_properties, interval_includes

Examples

  non_empty   <- 1900 %to% 2000
  empty       <- 2000 %to% 2000
  improper    <- 2000 %to% 1900
  na          <- NA_datey_interval_

  is_collapsed(non_empty) # FALSE
  is_collapsed(empty)     # TRUE
  is_collapsed(improper)  # TRUE
  is_collapsed(na)        # TRUE

  is_proper(non_empty)    # TRUE
  is_proper(empty)        # TRUE
  is_proper(improper)     # FALSE
  is_proper(na)           # FALSE

datey documentation built on July 14, 2026, 5:06 p.m.