Class: Proj::Unit

Inherits:
Object
  • Object
show all
Defined in:
lib/proj/unit.rb

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(auth_name, code, name, category, conv_factor, proj_short_name, deprecated) ⇒ Unit

Create a new Unit

Parameters:

  • auth_name (String) —

    Authority name

  • code (String) —

    Object code

  • name (String) —

    Object name. For example “metre”, “US survey foot”, etc

  • category (String) —

    Category of the unit: one of “linear”, “linear_per_time”, “angular”, “angular_per_time”, “scale”, “scale_per_time” or “time”

  • conv_factor (String) —

    Conversion factor to apply to transform from that unit to the corresponding SI unit (metre for “linear”, radian for “angular”, etc.). It might be 0 in some cases to indicate no known conversion factor

  • proj_short_name (String) —

    PROJ short name, like “m”, “ft”, “us-ft”, etc… Might be nil

  • deprecated (Boolean) —

    Whether the object is deprecated



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# File 'lib/proj/unit.rb', line 63

def initialize(auth_name, code, name, category, conv_factor, proj_short_name, deprecated)
  @auth_name = auth_name
  @code = code
  @name = name
  @category = category
  @conv_factor = conv_factor
  @proj_short_name = proj_short_name
  @deprecated = deprecated
end

Instance Attribute Details

#auth_name ⇒ String (readonly)

Returns Authority name.

Returns:

  • (String) —

    Authority name



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# File 'lib/proj/unit.rb', line 17

def auth_name
  @auth_name
end

#category ⇒ String (readonly)

Returns Category of the unit: one of “linear”, “linear_per_time”, “angular”, “angular_per_time”, “scale”, “scale_per_time” or “time”.

Returns:

  • (String) —

    Category of the unit: one of “linear”, “linear_per_time”, “angular”, “angular_per_time”, “scale”, “scale_per_time” or “time”



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# File 'lib/proj/unit.rb', line 17

attr_reader :auth_name, :code, :name, :category, :conv_factor, :proj_short_name, :deprecated

#code ⇒ String (readonly)

Returns Object code.

Returns:

  • (String) —

    Object code



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# File 'lib/proj/unit.rb', line 17

attr_reader :auth_name, :code, :name, :category, :conv_factor, :proj_short_name, :deprecated

#conv_factor ⇒ String (readonly)

Returns Conversion factor to apply to transform from that unit to the corresponding SI unit (metre for “linear”, radian for “angular”, etc.). It might be 0 in some cases to indicate no known conversion factor.

Returns:

  • (String) —

    Conversion factor to apply to transform from that unit to the corresponding SI unit (metre for “linear”, radian for “angular”, etc.). It might be 0 in some cases to indicate no known conversion factor



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# File 'lib/proj/unit.rb', line 17

attr_reader :auth_name, :code, :name, :category, :conv_factor, :proj_short_name, :deprecated

#deprecated ⇒ Object (readonly)

Returns the value of attribute deprecated.



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# File 'lib/proj/unit.rb', line 17

attr_reader :auth_name, :code, :name, :category, :conv_factor, :proj_short_name, :deprecated

#name ⇒ String (readonly)

Returns Object name. For example “metre”, “US survey foot”, etc.

Returns:

  • (String) —

    Object name. For example “metre”, “US survey foot”, etc



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# File 'lib/proj/unit.rb', line 17

attr_reader :auth_name, :code, :name, :category, :conv_factor, :proj_short_name, :deprecated

#proj_short_name ⇒ String (readonly)

Returns PROJ short name, like “m”, “ft”, “us-ft”, etc… Might be nil.

Returns:

  • (String) —

    PROJ short name, like “m”, “ft”, “us-ft”, etc… Might be nil



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# File 'lib/proj/unit.rb', line 17

attr_reader :auth_name, :code, :name, :category, :conv_factor, :proj_short_name, :deprecated

Class Method Details

.built_in(auth_name: nil, category: nil, allow_deprecated: false) ⇒ Object

Returns a list of built in Units. This is deprecated. Use Database#units instead



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# File 'lib/proj/unit.rb', line 20

def self.built_in(auth_name: nil, category: nil, allow_deprecated: false)
  # First get linear units
  pointer_to_array = FFI::Pointer.new(Api::PJ_UNITS, Api.proj_list_units)
  result = Array.new
  0.step do |i|
    unit_info = Api::PJ_UNITS.new(pointer_to_array[i])
    break if unit_info[:id].nil?
    result << self.new('PROJ', unit_info[:id], unit_info[:name],
                       'length', unit_info[:factor], unit_info[:id], false)
  end

  # Now get angular linear units
  if Api.method_defined?(:proj_list_angular_units)
    pointer_to_array = FFI::Pointer.new(Api::PJ_UNITS, Api.proj_list_angular_units)
    0.step do |i|
      unit_info = Api::PJ_UNITS.new(pointer_to_array[i])
      break result if unit_info[:id].nil?
      result << self.new('PROJ', unit_info[:id], unit_info[:name],
                         'angular', unit_info[:factor], unit_info[:id], false)
    end
  end

  if auth_name
    result = result.find_all {|unit_info| unit_info.auth_name == auth_name}
  end

  if category
    result = result.find_all {|unit_info| unit_info.category == category}
  end
  result
end

Instance Method Details

#<=>(other) ⇒ Object 



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# File 'lib/proj/unit.rb', line 73

def <=>(other)
  self.name <=> other.name
end

#==(other) ⇒ Object 



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# File 'lib/proj/unit.rb', line 77

def ==(other)
  self.auth_name == other.auth_name &&
  self.code == other.code
end

#inspect ⇒ Object 



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# File 'lib/proj/unit.rb', line 105

def inspect
  "#<#{self.class} authority=\"#{auth_name}\", code=\"#{code}\", name=\"#{name}\">"
end

#to_s ⇒ Object 



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# File 'lib/proj/unit.rb', line 101

def to_s
  self.name
end

#unit_type ⇒ Object 



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# File 'lib/proj/unit.rb', line 82

def unit_type
  case self.category
  when "linear"
    :PJ_UT_LINEAR
  when "linear_per_time"
    :PJ_UT_LINEAR
  when "angular"
    :PJ_UT_ANGULAR
  when "angular_per_time"
    :PJ_UT_ANGULAR
  when "scale"
    :PJ_UT_SCALE
  when "scale_per_time"
    :PJ_UT_SCALE
  when "time"
    :PJ_UT_TIME
  end
end