CODEWITHSUNDEEP
rubygeometrygeos
Charles Duporge
Charles Duporge

Reputation: 672

Geos ruby - Create point

I'm struggling using the GEOS library for Ruby, I just want to create a simple point with IRB. require geos return true so the install works. But the I don't really understand the documentation and nothing helps on the github page.

I tried Geos::Point.new('POINT(0 0)') but it returns a TypeError: allocator undefined for Geos::Point

Upvotes: 2

Views: 410

Answers (1)

Eric Duminil
Eric Duminil

Reputation: 54223

GEOS is a C++ library. It doesn't help much to look at the documentation there to learn the required Ruby syntax.

You'd need this rgeo gem.

Here's a good tutorial : "Geo-Rails Part 3: Spatial Data Types with RGeo"

As an example :

# gem install rgeo
require 'rgeo'

factory = RGeo::Cartesian.factory

point = factory.point(0, 0)
puts point
# POINT (0.0 0.0)

square = factory.parse_wkt("POLYGON((1 0, 0 1, -1 0, 0 -1, 1 0))")
puts square
# POLYGON ((1.0 0.0, 0.0 1.0, -1.0 0.0, 0.0 -1.0, 1.0 0.0))

puts square.contains?(point)
# true

Upvotes: 5

Related Questions