Function Repository Resource:

GeoGraphicsCases

Source Notebook

Select parts of a GeoGraphics object using geo feature type

Contributed by: Jon McLoone

ResourceFunction["GeoGraphicsCases"][gr,form]

returns a GeoGraphics containing only features that match patt.

ResourceFunction["GeoGraphicsCases"][gr,{form1,form2,…}]

returns a GeoGraphics containing only features that match any of the formi.

ResourceFunction["GeoGraphicsCases"][gr,Except[form]]

returns a GeoGraphics removing features that match form.

ResourceFunction["GeoGraphicsCases"][gr]

returns a list of feature types appropriate for form_i present in GeoGraphics gr.

Details and Options

ResourceFunction["GeoGraphicsCases"] can only be applied to maps with vector backgrounds.

Examples

Basic Examples (3)

Find the feature types present in a map of the Colosseum:

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Show only the "landcover" elements:

In[3]:=

$ResourceFunction["GeoGraphicsCases"][gr, {__, "landcover"}]$

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Show land cover and the buildings:

In[4]:=

$ResourceFunction[ "GeoGraphicsCases"][gr, {{__, "landcover"}, {_, "building", _}}]$

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Scope (3)

Wrapping the pattern or list of patterns with Except, removes those features and returns all others:

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In[6]:=

$ResourceFunction["GeoGraphicsCases"][gr, Except[{"fill", __}]]$

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Remove labels:

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$ResourceFunction["GeoGraphicsCases"][gr, Except[{"symbol", __}]]$

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Remove filled regions and labels:

In[8]:=

$ResourceFunction["GeoGraphicsCases"][gr, Except[{{"fill", __}, {_, "building", _}}]]$

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Options (2)

Some GeoGraphics also contain textured backgrounds. For example, selecting the transportation network for the UK also displays a landtype bitmap background:

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$ResourceFunction["GeoGraphicsCases"][uk, {__, "transportation"}]$

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The option "RemoveTextures" can be used to remove bitmap textured polygons:

In[11]:=

$ResourceFunction["GeoGraphicsCases"][uk, {__, "transportation"}, "RemoveTextures" -> True]$

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Possible Issues (3)

GeoGraphicsCases works only on GeoGraphics with vector backgrounds:

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Sometimes GeoGraphics elements are only visible because they are expected to have contrasting elements behind them:

In[13]:=

$ResourceFunction["GeoGraphicsCases"][ GeoGraphics[Entity["Building", "Colosseum::pq39x"], GeoRange -> Quantity[500, "Feet"]], {_, "path_area_cycleway", "transportation"}]$

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You may need to replace colors to make them visible:

In[14]:=

$ResourceFunction["GeoGraphicsCases"][ GeoGraphics[Entity["Building", "Colosseum::pq39x"], GeoRange -> Quantity[500, "Feet"]], {_, "path_area_cycleway", "transportation"}] /. RGBColor[1., 1., 1.] -> Gray$