The library documents itself · Geo & cartography

stzGeoFeatures

32 own methods · 0 forms written with extensions, listed under their method

the source: base/geo/stzGeoFeatures.ring(opens in a new tab) · All classes · The area reference: Geo & cartography

Under each method, its extensions (Q CS XT Z ZZ IB W U): bold and ticked, it exists; struck, it does not. The extensions and what they mean

Examples: 0 come from the library's tests; 8 were composed from each method's signature and run for this page, on a fresh object, for example cJ = '{"type":"FeatureCollection","features":[{"type":"Feature","properties":{"name":"A"},"geometry":{"type":"Polygon","coordinates":[[[0,0],[4,0],[4,4],[0,4],[0,0]]]}}]}' o1 = StzGeoFeaturesFromJson(cJ). 24 methods have none yet. Examples run on 2026-10-03 20:51 inside the library at commit 0e72e2e2c.

Method

Explanation, as the source carries it

ReadGeoJson

readingno extension

ReadTopoJson

THE ARCS ARE SHARED AND THE NUMBERS ARE DELTAS. A TopoJSON stores each border once and every shape as the arcs that bound it; -1 means arc 0 walked backwards (the format writes ~i, which is -i-1). The positions inside an arc are cumulative sums on a quantised grid and become degrees through the transform.no extension

Count

what it holds

composed example

cJ = '{"type":"FeatureCollection","features":[{"type":"Feature","properties":{"name":"A"},"geometry":{"type":"Polygon","coordinates":[[[0,0],[4,0],[4,4],[0,4],[0,0]]]}}]}'
o1 = StzGeoFeaturesFromJson(cJ)
? o1.Count()
#--> 1

composed from the signature, run for this page

no extension

SkippedCount

how many geometries the reader could not use, counted rather than guessed at -- a record that drops counts what it dropped

composed example

cJ = '{"type":"FeatureCollection","features":[{"type":"Feature","properties":{"name":"A"},"geometry":{"type":"Polygon","coordinates":[[[0,0],[4,0],[4,4],[0,4],[0,0]]]}}]}'
o1 = StzGeoFeaturesFromJson(cJ)
? o1.SkippedCount()
#--> 0

composed from the signature, run for this page

no extension

KindOf

(no comment in the source: the name reads as a sentence) kind ofno extension

IdOf

(no comment in the source: the name reads as a sentence) id ofno extension

PropertiesOf

(no comment in the source: the name reads as a sentence) properties ofno extension

PropertyOf

(no comment in the source: the name reads as a sentence) property ofno extension

HasProperty

(no comment in the source: the name reads as a sentence) has propertyno extension

NameOf

what the file calls it: the first of the usual name keys it carries, or its id, or "" -- and the caller who knows better says so themselvesno extension

IndexOfName

(no comment in the source: the name reads as a sentence) index of name

composed example

cJ = '{"type":"FeatureCollection","features":[{"type":"Feature","properties":{"name":"A"},"geometry":{"type":"Polygon","coordinates":[[[0,0],[4,0],[4,4],[0,4],[0,0]]]}}]}'
o1 = StzGeoFeaturesFromJson(cJ)
? o1.IndexOfName("a")
#--> 1

composed from the signature, run for this page

no extension

PartsOf

(no comment in the source: the name reads as a sentence) parts ofno extension

PartCount

(no comment in the source: the name reads as a sentence) part countno extension

RingsOf

a part's rings: [1] is the outer edge, every one after it is a HOLEno extension

OuterRingOf

(no comment in the source: the name reads as a sentence) outer ring ofno extension

HoleCountOf

(no comment in the source: the name reads as a sentence) hole count ofno extension

PointsOf

every lon/lat this feature holds, flat -- what FitToPoints takesno extension

AllPoints

(no comment in the source: the name reads as a sentence) all points

composed example

cJ = '{"type":"FeatureCollection","features":[{"type":"Feature","properties":{"name":"A"},"geometry":{"type":"Polygon","coordinates":[[[0,0],[4,0],[4,4],[0,4],[0,0]]]}}]}'
o1 = StzGeoFeaturesFromJson(cJ)
? @@( o1.AllPoints() )
#--> [ 0, 0, 4, 0, 4, 4, 0, 4, 0, 0 ]

composed from the signature, run for this page

no extension

BoundsOf

[ lonMin, latMin, lonMax, latMax ]no extension

Bounds

(no comment in the source: the name reads as a sentence) bounds

composed example

cJ = '{"type":"FeatureCollection","features":[{"type":"Feature","properties":{"name":"A"},"geometry":{"type":"Polygon","coordinates":[[[0,0],[4,0],[4,4],[0,4],[0,0]]]}}]}'
o1 = StzGeoFeaturesFromJson(cJ)
? @@( o1.Bounds() )
#--> [ 0, 0, 4, 4 ]

composed from the signature, run for this page

no extension

AreaKm2Of

the biggest part by point count -- the mainland, and the only thing DN24b's reader ever kept A FEATURE'S AREA ON THE SPHERE, km2, with its holes taken out and all its parts added in. This lived in stzGeoMap.ValuesFromArea and moved here when the point patterns (GE7a) needed a window's area and the map's own copy would have been a second one -- duplicated logic diverges, and it diverges in cost first. THE AREA OF A FEATURE, km2, ON WGS84 SINCE GE8 -- outer rings added and holes taken out, which is what makes a country with a lake come out as the land and not as the outline.no extension

AreasKm2

every feature's area, in feature orderno extension

AreaKm2

the whole set's area: what a point pattern observed over all of it divides by

composed example

cJ = '{"type":"FeatureCollection","features":[{"type":"Feature","properties":{"name":"A"},"geometry":{"type":"Polygon","coordinates":[[[0,0],[4,0],[4,4],[0,4],[0,0]]]}}]}'
o1 = StzGeoFeaturesFromJson(cJ)
? o1.AreaKm2()
#--> 196869.60

composed from the signature, run for this page

no extension

LargestPartOf

(no comment in the source: the name reads as a sentence) largest part ofno extension

Contains

THE BOX FIRST. A ring test walks every edge; a box test is four comparisons, and for a point that is not in this region -- which is almost every pair a spatial join asks about -- the box is the whole answer.no extension

PartContains

is this place inside ONE PART of this feature? What a label placer asks: a name belongs in the part it was measured against, not merely somewhere in the country.no extension

IndexAt

which feature is at this place, or 0 -- what a click will ask

composed example

cJ = '{"type":"FeatureCollection","features":[{"type":"Feature","properties":{"name":"A"},"geometry":{"type":"Polygon","coordinates":[[[0,0],[4,0],[4,4],[0,4],[0,0]]]}}]}'
o1 = StzGeoFeaturesFromJson(cJ)
? o1.IndexAt(2, 5)
#--> 0

composed from the signature, run for this page

no extension

Subset

taking part of a file ------------------------------------------------ SOME OF THE FEATURES, as a feature set of their own. Everything else -- the map, the atlas, the rules -- takes a feature set, so a subset is a first-class thing and not a list of indices the caller has to carry around beside it.no extension

Adopt

(no comment in the source: the name reads as a sentence) adoptno extension

IndicesWithin

THE FEATURES WHOSE MIDDLE FALLS IN A BOX, by index. What "metropolitan France" means to a file that also carries Réunion and Guyane: not a political statement, a WINDOW -- the caller says which piece of the world they are drawing, and the file is unchanged.no extension

Within

(no comment in the source: the name reads as a sentence) withinno extension

AsRegions

the regions the choropleth builder takes, so a file read here can go straight into DN24's picture: [ name, value, flatOuterRing ] each, from the LARGEST part of every feature

composed example

cJ = '{"type":"FeatureCollection","features":[{"type":"Feature","properties":{"name":"A"},"geometry":{"type":"Polygon","coordinates":[[[0,0],[4,0],[4,4],[0,4],[0,0]]]}}]}'
o1 = StzGeoFeaturesFromJson(cJ)
? @@( o1.AsRegions("a") )
#--> [ [ "A", "", [ 0, 0, 4, 0, 4, 4, 0, 4, 0, 0 ] ] ]

composed from the signature, run for this page

no extension