GeoZoomLevel
is an option for specifying the resolution at which to render a map.
Details
- GeoZoomLevel is an option for geo visualization functions like GeoGraphics, GeoImage, GeoListPlot or GeoHistogram, and for geo data functions like GeoElevationData, GeomagneticModelData or GeogravityModelData.
- GeoZoomLevel provides a base 2 logarithmic specification of map scale. An increase by 1 in geo zoom level corresponds to an increase in distance resolution by a factor of 2. A GeoZoomLevel value of 1 corresponds to data for the whole world.
- GeoZoomLevel values are used both to estimate map geo ranges around a given location and to decide the resolution of the geo image tiles or data tiles to download.
- Different geo background styles and data sources have different ranges of available zooms. For example, the "StreetMap" geo styling for Earth is available from zooms 1 to 18, while geo elevation data is available for zooms 1 to 12 for Earth, or zooms 1 to 7 for Mars.
Examples
open all close allBasic Examples (3)
Display a map of Canada with default GeoZoomLevel:
GeoGraphics[Entity["Country", "Canada"]]Explicitly specify GeoZoomLevel to obtain a lower-resolution map rendering:
GeoGraphics[Entity["Country", "Canada"], GeoZoomLevel -> 1]Display a map around New York City with default GeoZoomLevel:
GeoGraphics[Entity["City", {"NewYork", "NewYork", "UnitedStates"}]]Explicitly specify GeoZoomLevel to obtain a higher-resolution map rendering:
GeoGraphics[Entity["City", {"NewYork", "NewYork", "UnitedStates"}], GeoZoomLevel -> 12]Display a relief map rendering of the region surrounding New York state using default GeoZoomLevel:
GeoGraphics[Entity["AdministrativeDivision", {"NewYork", "UnitedStates"}], GeoBackground -> GeoStyling["ReliefMap"]]Explicitly specify the GeoZoomLevel to obtain a lower-resolution map rendering:
GeoGraphics[Entity["AdministrativeDivision", {"NewYork", "UnitedStates"}], GeoBackground -> GeoStyling["ReliefMap"], GeoZoomLevel -> 3]Scope (2)
Increase zoom around a given position, with automatic computation of ranges and preserving image resolution:
Table[GeoGraphics[Entity["Building", "Alhambra"], GeoZoomLevel -> n, GeoBackground -> "Plain"], {n, 18}]Increase zoom around a given position, with fixed geo range and automatic computation of image resolution:
Table[GeoGraphics[Entity["HistoricalSite", "CastelSantAngelo::q6839"], GeoZoomLevel -> n, GeoRange -> Quantity[100, "Meters"]], {n, 10, 18}]Properties & Relations (2)
Approximate distances for maps of the Earth of a given zoom at a given location:
loc = GeoPosition[Entity["HistoricalSite", "CastelSantAngelo::q6839"]]equator = 2Pi GeodesyData["ITRF00", "SemimajorAxis"]Table[{zoom, equator / 2 ^ zoom}, {zoom, 0, 18}]//GridThose distances correspond to the diameter of a circle inscribed on the map:
GeoGraphics[loc, GeoScaleBar -> "Metric", GeoZoomLevel -> 18]GeoGraphics[GeoCircle[loc, Quantity[152.874, "Meters"] / 2], GeoScaleBar -> "Metric"]For a given location, GeoZoomLevel specifies the scale of the map:
loc = GeoPosition[Entity["Building", "BrandenburgerTor::r5479"]]GeoImage[loc, GeoZoomLevel -> 18]GeoResolution specifies the distance between neighboring pixels:
GeoImage[loc, GeoResolution -> Quantity[35, "Centimeters"]]Possible Issues (3)
Very high zoom level may result in an excessive number of tiles requested:
GeoGraphics[Entity["Country", "Canada"], GeoZoomLevel -> 7]
Not every GeoZoomLevel is available for every location in GeoElevationData:
pos = GeoPosition[Entity["City", {"Kathmandu", "Kathmandu", "Nepal"}]]Table[GeoElevationData[pos, GeoZoomLevel -> n], {n, 15}]
Text annotations in certain geo styles are more easily readable at some size and zoom combinations than others:
With[{loc = Entity["Building", "TourEiffel"]}, GeoGraphics[{Red, PointSize[Large], Point[loc]}, GeoCenter -> loc, GeoRange -> Quantity[100, "Meters"], GeoZoomLevel -> #, GeoBackground -> "StreetMap"]]& /@ Range[13, 18]Text
Wolfram Research (2014), GeoZoomLevel, Wolfram Language function, https://reference.wolfram.com/language/ref/GeoZoomLevel.html.
CMS
Wolfram Language. 2014. "GeoZoomLevel." Wolfram Language & System Documentation Center. Wolfram Research. https://reference.wolfram.com/language/ref/GeoZoomLevel.html.
APA
Wolfram Language. (2014). GeoZoomLevel. Wolfram Language & System Documentation Center. Retrieved from https://reference.wolfram.com/language/ref/GeoZoomLevel.html