Area, a standard type

An area: 12sqm or 2ha.

Use it for floor space or land. A Length times a Length gives one. For a drawn shape on a map, use Polygon, which geo.area measures.

Shape

One value, with no fields to fill in. As text it reads 10000 sqm.

Example

example

Area(12sqm)

text.parse(raw, as: Area) reads one from text that comes from outside. Text that isn't one at all fails malformed, such as 5, 1.2.3 or five.

These operations give one: geo.area, units.of and units.sum.

Good to know

It is held in square metres to 6 places.
== tells you whether two are the same, and < and list.sort_by compare and sort them.

In JSON

An object of its parts, in a request, a response or json.write:

json

{"value":"0.5","unit":"sqm"}{"value":"12","unit":"sqm"}{"value":"10000","unit":"sqm"}

Details

Text form, storage, how it is shown, and operations

Area is in the group Physical quantities, and has been in Jadpo since 0.1.0.

Text form

text.from writes one standard text form, the same form text.parse reads back: 0.5 sqm, 12 sqm and 10000 sqm.

How it is stored

It is stored in one column named for the field, of type numeric(38, 6), holding the area in square metres (m²). 12 sqm is stored as 12.

How it is shown to people

text.format(value, locale:) shows it to people in their locale. A call may also give unit:.

With locale: Locale.en_gb:

Value	Shown
`0.5 sqm`	`0.5 m²`
`12 sqm`	`12 m²`
`10000 sqm`	`10,000 m²`

Operations

geo.area(shape: T) -> Area: A Polygon's or MultiPolygon's area on the ellipsoid, each edge a geodesic and each ring the smaller of the two sides it bounds, holes taken away, rounded half to even to the square millimetre.
units.in(value: Quantity, unit: QuantityUnit, scale: Int, rounding: Rounding) -> Decimal: value in unit, a unit of its kind, as a Decimal of scale places rounded by rounding: units.in(5km, LengthUnit.mile, scale: 2, rounding: Rounding.half_even) is 3.11.
units.of(value: Number, unit: QuantityUnit) -> Quantity: value of unit, an Int or a Decimal, as the quantity of unit's kind, converted exactly to the base unit and rounded half to even to the kind's scale: units.of(5, LengthUnit.mile).
units.sum(items: List<Quantity>) -> Quantity: The items added up, all of one kind; nothing for no items. A Temperature or a SoundLevel doesn't add to itself, so neither is summed.

It also takes text.parse, text.from, text.format, json.read, json.write and ==. How every standard type behaves says how they work.