Decimal degrees
notation for angular measurements, typically for latitude and longitude
Decimal degrees (DD) is a notation for expressing latitude and longitude geographic coordinates as decimal fractions of a degree. DD are used in many geographic information systems (GIS), web mapping applications such as OpenStreetMap, and GPS devices. Decimal degrees are an alternative to using degrees-minutes-seconds (DMS) notation. As with latitude and longitude, the values are bounded by ±90° and ±180° respectively.
Positive latitudes are north of the equator, negative latitudes are south of the equator. Positive longitudes are east of the Prime Meridian; negative longitudes are west of the Prime Meridian. Latitude and longitude are usually expressed in that sequence, latitude before longitude. The abbreviation [dLL] has been used in the scientific literature with locations in texts being identified as a tuple within square brackets, for example [54.5798, -3.5820]. The appropriate decimal places are used, negative values are given using a hyphen-minus character. The designation of a location as, for example [54.1855, -2.9857] means that it is potentially computer searchable and that it can be located by a generally (open) referencing system such as Google Earth or OpenStreetMap.
The public source identifies “Decimal degrees” as notation for angular measurements, typically for latitude and longitude. This brief keeps that definition visible, then builds a research path around Decimal, degrees and notation.
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This entry incorporates text from “Decimal degrees” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.