wkt2geojson: Convert WKT to GeoJSON-like objects.

In ropensci/wellknown: Convert Between 'WKT' and 'GeoJSON'

Convert WKT to GeoJSON-like objects.

Description

Convert WKT to GeoJSON-like objects.

Usage

wkt2geojson(str, fmt = 16, feature = TRUE, numeric = TRUE, simplify = FALSE)

Arguments

str	A GeoJSON-like object representing a Point, LineString, Polygon, MultiPolygon, etc.
fmt	Format string which indicates the number of digits to display after the decimal point when formatting coordinates. Max: 20
feature	(logical) Make a feature geojson object. Default: TRUE
numeric	(logical) Give back values as numeric. Default: TRUE
simplify	(logical) Attempt to simplify from a multi- geometry type to a single type. Applies to multi features only. Default: FALSE

Details

Should be robust against a variety of typing errors, including extra spaces between coordinates, no space between WKT type and coordinates. However, some things won't pass, including lowercase WKT types, no spaces between coordinates.

WKT with a 3rd value and when Z is found will be left as is and assumed to be a altitude or similar value. WKT with a 3rd value and when M is found will be discarded as the GeoJSON spec says to do so. WKT with a 4th value as (presumably as a measurement) will also be discarded.

References

https://tools.ietf.org/html/rfc7946

See Also

geojson2wkt()

Examples

# point
str <- "POINT (-116.4000000000000057 45.2000000000000028)"
wkt2geojson(str)
wkt2geojson(str, feature=FALSE)
wkt2geojson(str, numeric=FALSE)
wkt2geojson("POINT (-116 45)")
wkt2geojson("POINT (-116 45 0)")
## 3D
wkt2geojson("POINT Z(100 3 35)")
wkt2geojson("POINT M(100 3 35)") # dropped if M
## 4D
wkt2geojson("POINT ZM(100 3 35 1.5)") # Z retained

# multipoint
str <- 'MULTIPOINT ((100.000 3.101), (101.000 2.100), (3.140 2.180))'
wkt2geojson(str, fmt = 2)
wkt2geojson(str, fmt = 2, feature=FALSE)
wkt2geojson(str, numeric=FALSE)
wkt2geojson("MULTIPOINT ((100 3), (101 2), (3 2))")
wkt2geojson("MULTIPOINT ((100 3 0), (101 2 0), (3 2 0))")
wkt2geojson("MULTIPOINT ((100 3 0 1), (101 2 0 1), (3 2 0 1))") 
## 3D
wkt2geojson("MULTIPOINT Z((100 3 35), (101 2 45), (3 2 89))")
wkt2geojson("MULTIPOINT M((100 3 1.3), (101 2 1.4), (3 2 1.9))")
## 4D
wkt2geojson("MULTIPOINT ZM((100 3 35 0), (101 2 45 0), (3 2 89 0))")

## simplify
wkt2geojson("MULTIPOINT ((100 3))", simplify = FALSE)
wkt2geojson("MULTIPOINT ((100 3))", simplify = TRUE)


# polygon
str <- "POLYGON ((100 0.1, 101.1 0.3, 101 0.5, 100 0.1),
   (103.2 0.2, 104.8 0.2, 100.8 0.8, 103.2 0.2))"
wkt2geojson(str)
wkt2geojson(str, feature=FALSE)
wkt2geojson(str, numeric=FALSE)
## 3D
str <- "POLYGON Z((100 0.1 3, 101.1 0.3 1, 101 0.5 5, 100 0.1 8),
   (103.2 0.2 3, 104.8 0.2 4, 100.8 0.8 5, 103.2 0.2 9))"
wkt2geojson(str)
## 4D
str <- "POLYGON ZM((100 0.1 3 0, 101.1 0.3 1 0, 101 0.5 5 0, 100 0.1 8 0),
   (103.2 0.2 3 0, 104.8 0.2 4 0, 100.8 0.8 5 0, 103.2 0.2 9 0))"
wkt2geojson(str)


# multipolygon
str <- "MULTIPOLYGON (((40 40, 20 45, 45 30, 40 40)),
 ((20 35, 45 20, 30 5, 10 10, 10 30, 20 35), (30 20, 20 25, 20 15, 30 20)))"
wkt2geojson(str)
wkt2geojson(str, feature=FALSE)
wkt2geojson(str, numeric=FALSE)
## 3D
str <- "MULTIPOLYGON Z(((40 40 1, 20 45 3, 45 30 10, 40 40 0)),
 ((20 35 5, 45 20 67, 30 5 890, 10 10 2, 10 30 0, 20 35 4), 
 (30 20 4, 20 25 54, 20 15 56, 30 20 89)))"
wkt2geojson(str)
## 4D
str <- "MULTIPOLYGON ZM(((40 40 1 0, 20 45 3 4, 45 30 10 45, 40 40 0 1)),
 ((20 35 5 8, 45 20 67 9, 30 5 890 89, 10 10 2 234, 10 30 0 5, 20 35 4 1), 
 (30 20 4 0, 20 25 54 5, 20 15 56 55, 30 20 89 78)))"
wkt2geojson(str)

# simplify multipolygon to polygon if possible
str <- "MULTIPOLYGON (((40 40, 20 45, 45 30, 40 40)))"
wkt2geojson(str, simplify = FALSE)
wkt2geojson(str, simplify = TRUE)


# linestring
str <- "LINESTRING (100.000 0.000, 101.000 1.000)"
wkt2geojson(str)
wkt2geojson(str, feature = FALSE)
wkt2geojson("LINESTRING (0 -1, -2 -3, -4 5)")
wkt2geojson("LINESTRING (0 1 2, 4 5 6)")
wkt2geojson(str, numeric = FALSE)
## 3D
wkt2geojson("LINESTRING Z(100.000 0.000 3, 101.000 1.000 5)")
wkt2geojson("LINESTRING M(100.000 0.000 10, 101.000 1.000 67)")
## 4D
wkt2geojson("LINESTRING ZM(100 0 1 4, 101 1 5 78)")


# multilinestring
str <- "MULTILINESTRING ((30 1, 40 30, 50 20)(10 0, 20 1))"
wkt2geojson(str)
wkt2geojson(str, numeric=FALSE)

str <- "MULTILINESTRING (
   (-105.0 39.5, -105.0 39.5, -105.0 39.5, -105.0 39.5,
     -105.0 39.5, -105.0 39.5),
   (-105.0 39.5, -105.0 39.5, -105.0 39.5),
   (-105.0 39.5, -105.0 39.5, -105.0 39.5, -105.0 39.5, -105.0 39.5),
   (-105.0 39.5, -105.0 39.5, -105.0 39.5, -105.0 39.5))"
wkt2geojson(str)
wkt2geojson(str, numeric=FALSE)

## 3D
str <- "MULTILINESTRING Z((30 1 0, 40 30 0, 50 20 0)(10 0 1, 20 1 1))"
wkt2geojson(str)
str <- "MULTILINESTRING M((30 1 0, 40 30 0, 50 20 0)(10 0 1, 20 1 1))"
wkt2geojson(str)
## 4D
str <- "MULTILINESTRING ZM((30 1 0 5, 40 30 0 7, 50 20 0 1)(10 0 1 1, 20 1 1 1))"
wkt2geojson(str)

# simplify multilinestring to linestring if possible
str <- "MULTILINESTRING ((30 1, 40 30, 50 20))"
wkt2geojson(str, simplify = FALSE)
wkt2geojson(str, simplify = TRUE)


# Geometrycollection
str <- "GEOMETRYCOLLECTION (
 POINT Z(0 1 4),
 LINESTRING (-100 0, -101 -1),
 POLYGON ((100.001 0.001, 101.1235 0.0010, 101.001 1.001, 100.001 0.001),
           (100.201 0.201, 100.801 0.201, 100.801 0.801, 100.201 0.201)),
 MULTIPOINT ((100.000 3.101), (101.0 2.1), (3.14 2.18)),
 MULTILINESTRING ((0 -1, -2 -3, -4 -5),
       (1.66 -31.50, 10.0 3.0, 10.9 1.1, 0.0 4.4)),
 MULTIPOLYGON (((100.001 0.001, 101.001 0.001, 101.001 1.001, 100.001 0.001),
               (100.201 0.201, 100.801 0.201, 100.801 0.801, 100.201 0.201)),
                 ((1 2 3, 5 6 7, 9 10 11, 1 2 3))))"
wkt2geojson(str)
wkt2geojson(str, numeric=FALSE)

# case doesn't matter
str <- "point (-116.4000000000000057 45.2000000000000028)"
wkt2geojson(str)

ropensci/wellknown documentation built on April 8, 2023, 11:54 p.m.