GeoWithinQ[reg,loc]
returns True if the location loc is contained within the region reg, and False otherwise.
GeoWithinQ[reg]
represents an operator form of GeoWithinQ that can be applied to a location.


GeoWithinQ

GeoWithinQ[reg,loc]
returns True if the location loc is contained within the region reg, and False otherwise.
GeoWithinQ[reg]
represents an operator form of GeoWithinQ that can be applied to a location.
Details and Options

- In GeoWithinQ[reg,loc], reg can be specified as an entity of a geo domain such as "City", "Country" or "HistoricalCountry"; a Dated[…] object; a GeoVariant[…] expression or an extended GeoGraphics primitive. The location loc can additionally be specified as a GeoPosition or related point-like location object.
- For time-dependent entities, GeoWithinQ[reg,loc] returns by default whether loc is contained in reg at some moment in their history. If the entities have different time spans, then GeoWithinQ returns False.
- Dated[entity,dates] can be used to restrict a time-dependent entity to a given date or interval of dates. GeoVariant[entity,"UnionArea"] can be used to make the computation ignore date information.
- GeoWithinQ accepts lists in both arguments, effectively calling Outer on the input lists.
- GeoWithinQ[reg][loc] is equivalent to GeoWithinQ[reg,loc].
- With the option setting "FullyContained"->True, GeoWithinQ[reg,loc] will return True only if loc is completely contained in reg.
Examples
open all close allBasic Examples (2)
Scope (8)
Geographic Data (5)
Test whether France is included in the following polygon:
Visualize France and the polygon:
Test whether several airports are inside the city of Chicago:
Test whether a particular location is inside several different regions:
Test several cities for membership in several regions simultaneously:
Each row is the result for all locations with respect to a single region:
Use GeoWithinQ as an operator form:
Historical Data (3)
The location of the battle of Zama was not yet in the Roman Republic when the battle took place:
The location of the battle of Zama was in the Roman Republic later in time:
The location of the city of Paris was not in the Roman Republic in year 250 BC:
It was included in the Roman Republic in year 50 BC:
The Republic of Venice was never in the Roman Empire because they did not overlap in time:
GeoVariant[entity,"UnionArea"] represents the union of all polygons of entity at all times in its history, making GeoWithinQ ignore temporal information:
Options (1)
"FullyContained" (1)
The United Kingdom is considered to be inside London, since the two entities overlap:
The option "FullyContained"->True excludes regions that extend outside the entity:
London is always considered to be inside the United Kingdom:
Applications (1)
Properties & Relations (2)
GeoWithinQ[list1,list2] is essentially equivalent to Outer[GeoWithinQ,list1,list2]:
GeoWithinQ could be implemented using a combination of GeoNearest and MemberQ:
GeoNearest allows radii to be specified:
Possible Issues (2)
With the default option value "FullyContained"False, GeoWithinQ checks for polygon intersection, which may lead to unexpected results:
GeoWithinQ uses by default the "PrincipalArea" geo variant of a country, which for Spain contains the Canary islands:
Use "FullyContained"True to check for actual containment:
Or use a geo variant that does not include the overlapping region:
GeoWithinQ[entity,loc] uses the polygon available for the given entity, which may not have enough resolution to resolve certain locations correctly, most importantly near the coast:
Therefore this restricted Interpreter call fails:
See Also
GeoIdentify GeoEntities GeoNearest MemberQ RegionMember GeoBounds GeoBoundingBox GeoVisibleRegion
Entity Types: Country City GeographicRegion
Related Guides
Text
Wolfram Research (2014), GeoWithinQ, Wolfram Language function, https://reference.wolfram.com/language/ref/GeoWithinQ.html (updated 2024).
CMS
Wolfram Language. 2014. "GeoWithinQ." Wolfram Language & System Documentation Center. Wolfram Research. Last Modified 2024. https://reference.wolfram.com/language/ref/GeoWithinQ.html.
APA
Wolfram Language. (2014). GeoWithinQ. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/GeoWithinQ.html
BibTeX
@misc{reference.wolfram_2025_geowithinq, author="Wolfram Research", title="{GeoWithinQ}", year="2024", howpublished="\url{https://reference.wolfram.com/language/ref/GeoWithinQ.html}", note=[Accessed: 11-August-2025]}
BibLaTeX
@online{reference.wolfram_2025_geowithinq, organization={Wolfram Research}, title={GeoWithinQ}, year={2024}, url={https://reference.wolfram.com/language/ref/GeoWithinQ.html}, note=[Accessed: 11-August-2025]}