Module: Geokit::Mappable::ClassMethods
- Defined in:
- lib/geokit/mappable.rb
Overview
:nodoc:
Instance Method Summary collapse
-
#decimal_to_dms(deg) ⇒ Object
Given a decimal degree like -87.660333 return a 3-element array like [ -87, 39, 37.198… ].
-
#distance_between(from, to, options = {}) ⇒ Object
Returns the distance between two points.
- #distance_between_flat(from, to, units) ⇒ Object
- #distance_between_sphere(from, to, units) ⇒ Object
-
#endpoint(start, heading, distance, options = {}) ⇒ Object
Given a start point, distance, and heading (in degrees), provides an endpoint.
-
#geocode(location, options = {}) ⇒ Object
Geocodes a location using the multi geocoder.
-
#heading_between(from, to) ⇒ Object
Returns heading in degrees (0 is north, 90 is east, 180 is south, etc) from the first point to the second point.
-
#math_error_classes ⇒ Object
Ruby 1.9 raises Math::DomainError, but it is not defined in Ruby 1.8.
-
#midpoint_between(from, to, options = {}) ⇒ Object
Returns the midpoint, given two points.
Instance Method Details
#decimal_to_dms(deg) ⇒ Object
Given a decimal degree like -87.660333 return a 3-element array like [ -87, 39, 37.198… ]
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# File 'lib/geokit/mappable.rb', line 132 def decimal_to_dms(deg) return false unless deg.is_a?(Numeric) # seconds is 0...3599.999, representing the entire fractional part. seconds = (deg.abs % 1.0) * 3600.0 [ deg.to_i, # degrees as positive or negative integer (seconds / 60).to_i, # minutes as positive integer (seconds % 60) # seconds as positive float ] end |
#distance_between(from, to, options = {}) ⇒ Object
Returns the distance between two points. The from and to parameters are required to have lat and lng attributes. Valid options are: :units - valid values are :miles, :kms, :nms (Geokit::default_units is the default) :formula - valid values are :flat or :sphere (Geokit::default_formula is the default)
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# File 'lib/geokit/mappable.rb', line 36 def distance_between(from, to, ={}) from=Geokit::LatLng.normalize(from) to=Geokit::LatLng.normalize(to) return 0.0 if from == to # fixes a "zero-distance" bug units = [:units] || Geokit::default_units formula = [:formula] || Geokit::default_formula case formula when :sphere then distance_between_sphere(from, to, units) when :flat then distance_between_flat(from, to, units) end end |
#distance_between_flat(from, to, units) ⇒ Object
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# File 'lib/geokit/mappable.rb', line 57 def distance_between_flat(from, to, units) lat_length = units_per_latitude_degree(units) * (from.lat - to.lat) lng_length = units_per_longitude_degree(from.lat, units) * (from.lng - to.lng) Math.sqrt(lat_length ** 2 + lng_length ** 2) end |
#distance_between_sphere(from, to, units) ⇒ Object
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# File 'lib/geokit/mappable.rb', line 48 def distance_between_sphere(from, to, units) lat_sin = Math.sin(deg2rad(from.lat)) * Math.sin(deg2rad(to.lat)) lat_cos = Math.cos(deg2rad(from.lat)) * Math.cos(deg2rad(to.lat)) lng_cos = Math.cos(deg2rad(to.lng) - deg2rad(from.lng)) units_sphere_multiplier(units) * Math.acos(lat_sin + lat_cos * lng_cos) rescue *math_error_classes 0.0 end |
#endpoint(start, heading, distance, options = {}) ⇒ Object
Given a start point, distance, and heading (in degrees), provides an endpoint. Returns a LatLng instance. Typically, the instance method will be used instead of this method.
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# File 'lib/geokit/mappable.rb', line 87 def endpoint(start,heading, distance, ={}) units = [:units] || Geokit::default_units ratio = distance.to_f / units_sphere_multiplier(units) start = Geokit::LatLng.normalize(start) lat = deg2rad(start.lat) lng = deg2rad(start.lng) heading = deg2rad(heading) sin_ratio = Math.sin(ratio) cos_ratio = Math.cos(ratio) sin_lat = Math.sin(lat) cos_lat = Math.cos(lat) end_lat = Math.asin(sin_lat * cos_ratio + cos_lat * sin_ratio * Math.cos(heading)) end_lng = lng + Math.atan2(Math.sin(heading) * sin_ratio * cos_lat, cos_ratio - sin_lat * Math.sin(end_lat)) LatLng.new(rad2deg(end_lat),rad2deg(end_lng)) end |
#geocode(location, options = {}) ⇒ Object
Geocodes a location using the multi geocoder.
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# File 'lib/geokit/mappable.rb', line 124 def geocode(location, = {}) res = Geocoders::MultiGeocoder.geocode(location, ) return res if res.success? raise Geokit::Geocoders::GeocodeError end |
#heading_between(from, to) ⇒ Object
Returns heading in degrees (0 is north, 90 is east, 180 is south, etc) from the first point to the second point. Typicaly, the instance methods will be used instead of this method.
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# File 'lib/geokit/mappable.rb', line 72 def heading_between(from,to) from=Geokit::LatLng.normalize(from) to=Geokit::LatLng.normalize(to) d_lng=deg2rad(to.lng-from.lng) from_lat=deg2rad(from.lat) to_lat=deg2rad(to.lat) y=Math.sin(d_lng) * Math.cos(to_lat) x=Math.cos(from_lat)*Math.sin(to_lat)-Math.sin(from_lat)*Math.cos(to_lat)*Math.cos(d_lng) heading=to_heading(Math.atan2(y,x)) end |
#math_error_classes ⇒ Object
Ruby 1.9 raises Math::DomainError, but it is not defined in Ruby 1.8
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# File 'lib/geokit/mappable.rb', line 64 def math_error_classes return [Errno::EDOM, Math::DomainError] if defined?(Math::DomainError) [Errno::EDOM] end |
#midpoint_between(from, to, options = {}) ⇒ Object
Returns the midpoint, given two points. Returns a LatLng. Typically, the instance method will be used instead of this method. Valid option:
:units - valid values are :miles, :kms, or :nms (:miles is the default)
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# File 'lib/geokit/mappable.rb', line 113 def midpoint_between(from,to,={}) from=Geokit::LatLng.normalize(from) units = [:units] || Geokit::default_units heading=from.heading_to(to) distance=from.distance_to(to,) midpoint=from.endpoint(heading,distance/2,) end |