Class: Alchemist::CompoundMeasurement

Inherits:
Object
  • Object
show all
Defined in:
lib/alchemist/compound_measurement.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(numerator) ⇒ CompoundMeasurement

Returns a new instance of CompoundMeasurement.



5
6
7
8
9
 
# File 'lib/alchemist/compound_measurement.rb', line 5

def initialize(numerator)
  @coefficient = 1
  @numerators = [numerator]
  @denominators = []
end

Dynamic Method Handling

This class handles dynamic methods through the method_missing method

#method_missing(method, *attrs, &block) ⇒ Object 



58
59
60
61
62
63
 
# File 'lib/alchemist/compound_measurement.rb', line 58

def method_missing(method, *attrs, &block)
  if Alchemist.library.measurement_for(method)
    @denominators << Alchemist.measure(1, method)
    consolidate
  end
end

Instance Attribute Details

#denominators ⇒ Object

Returns the value of attribute denominators.



3
4
5
 
# File 'lib/alchemist/compound_measurement.rb', line 3

def denominators
  @denominators
end

#numerators ⇒ Object

Returns the value of attribute numerators.



3
4
5
 
# File 'lib/alchemist/compound_measurement.rb', line 3

def numerators
  @numerators
end

Instance Method Details

#*(value) ⇒ Object 



11
12
13
14
15
16
17
18
19
20
 
# File 'lib/alchemist/compound_measurement.rb', line 11

def *(value)
  case value
  when Numeric
     @coefficient *= value
     self
  when Alchemist::Measurement
    @numerators << value
    return consolidate
  end
end

#compress_units ⇒ Object 



27
28
29
30
31
32
33
 
# File 'lib/alchemist/compound_measurement.rb', line 27

def compress_units
  @numerators.each_with_index do |numerator, n|
    @denominators.each_with_index do |denominator, d|
      remove_excess_units(numerator, n, denominator, d)
    end
  end
end

#consolidate ⇒ Object 



22
23
24
25
 
# File 'lib/alchemist/compound_measurement.rb', line 22

def consolidate
  compress_units
  set_coefficients
end

#remove_excess_units(numerator, n, denominator, d) ⇒ Object 



35
36
37
38
39
40
41
 
# File 'lib/alchemist/compound_measurement.rb', line 35

def remove_excess_units numerator, n, denominator, d
  if should_remove_units? numerator, denominator
    @numerators.delete_at(n)
    @denominators.delete_at(d)
    @coefficient *= (numerator / denominator)
  end
end

#set_coefficients ⇒ Object 



48
49
50
51
52
53
54
55
56
 
# File 'lib/alchemist/compound_measurement.rb', line 48

def set_coefficients
  if @denominators.length == 0 && @numerators.length == 1
    @numerators[0] * @coefficient
  elsif @denominators.length == 0 && @numerators.length == 0
    @coefficient
  else
    self
  end
end

#should_remove_units?(numerator, denominator) ⇒ Boolean

Returns:

  • (Boolean) 


43
44
45
46
 
# File 'lib/alchemist/compound_measurement.rb', line 43

def should_remove_units? numerator, denominator
  return false if numerator.is_a?(Numeric) || denominator.is_a?(Numeric)
  (Alchemist.library.measurement_for(numerator.unit_name) & Alchemist.library.measurement_for(denominator.unit_name)).length > 0
end