Class: RGeo::CoordSys::CS::CoordinateSystem

Inherits:
Info
  • Object
show all
Defined in:
lib/rgeo/coord_sys/cs/entities.rb

Overview

OGC spec description

Base interface for all coordinate systems.

A coordinate system is a mathematical space, where the elements of the space are called positions. Each position is described by a list of numbers. The length of the list corresponds to the dimension of the coordinate system. So in a 2D coordinate system each position is described by a list containing 2 numbers.

However, in a coordinate system, not all lists of numbers correspond to a position – some lists may be outside the domain of the coordinate system. For example, in a 2D Lat/Lon coordinate system, the list (91,91) does not correspond to a position.

Some coordinate systems also have a mapping from the mathematical space into locations in the real world. So in a Lat/Lon coordinate system, the mathematical position (lat, long) corresponds to a location on the surface of the Earth. This mapping from the mathematical space into real-world locations is called a Datum.

Notes

This is a non-instantiable abstract class. You must instantiate one of the subclasses GeocentricCoordinateSystem, GeographicCoordinateSystem, ProjectedCoordinateSystem, VerticalCoordinateSystem, LocalCoordinateSystem, or CompoundCoordinateSystem.

Instance Attribute Summary collapse

Attributes inherited from Info

#abbreviation, #alias, #authority, #authority_code, #name, #remarks

Instance Method Summary collapse

Methods inherited from Info

#extension

Methods inherited from Base

#_to_wkt, #encode_with, #eql?, #hash, #init_with, #inspect, #marshal_dump, #marshal_load, #to_s, #to_wkt

Constructor Details

#initialize(name_, dimension_, *optional_) ⇒ CoordinateSystem

:nodoc:



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# File 'lib/rgeo/coord_sys/cs/entities.rb', line 894

def initialize(name_, dimension_, *optional_) # :nodoc:
  super(name_, *optional_)
  @dimension = dimension_.to_i
end

Instance Attribute Details

#dimension ⇒ Object (readonly)

Dimension of the coordinate system



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# File 'lib/rgeo/coord_sys/cs/entities.rb', line 900

def dimension
  @dimension
end

Instance Method Details

#get_axis(_dimension_) ⇒ Object

Gets axis details for dimension within coordinate system. Each dimension in the coordinate system has a corresponding axis.



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# File 'lib/rgeo/coord_sys/cs/entities.rb', line 905

def get_axis(_dimension_)
  nil
end

#get_units(_dimension_) ⇒ Object

Gets units for dimension within coordinate system. Each dimension in the coordinate system has corresponding units.



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# File 'lib/rgeo/coord_sys/cs/entities.rb', line 912

def get_units(_dimension_)
  nil
end