Class: Quantity::Calculator
- Inherits:
-
Object
- Object
- Quantity::Calculator
- Includes:
- Quantifiable, Unit::SymbolConverter
- Defined in:
- lib/unitmanager/calculator.rb
Instance Attribute Summary collapse
-
#conversions ⇒ Object
readonly
Returns the value of attribute conversions.
-
#units ⇒ Object
readonly
Returns the value of attribute units.
Instance Method Summary collapse
- #add_conversion(params) ⇒ Object
- #add_unit(params) ⇒ Object
- #exp(return_as = nil) ⇒ Object
-
#initialize(units = {}, conversions = []) ⇒ Calculator
constructor
A new instance of Calculator.
- #perform_operation(first_operand, second_operand, operation) ⇒ Object
- #quantity(value, unit_sym) ⇒ Object
Methods included from Unit::SymbolConverter
Methods included from Quantifiable
Constructor Details
#initialize(units = {}, conversions = []) ⇒ Calculator
Returns a new instance of Calculator.
9 10 11 12 13 |
# File 'lib/unitmanager/calculator.rb', line 9 def initialize(units = {}, conversions = []) @units = units @parser ||= Unit::Parser.new(@units) @conversions ||= conversions end |
Instance Attribute Details
#conversions ⇒ Object (readonly)
Returns the value of attribute conversions.
7 8 9 |
# File 'lib/unitmanager/calculator.rb', line 7 def conversions @conversions end |
#units ⇒ Object (readonly)
Returns the value of attribute units.
7 8 9 |
# File 'lib/unitmanager/calculator.rb', line 7 def units @units end |
Instance Method Details
#add_conversion(params) ⇒ Object
57 58 59 60 61 62 63 64 65 66 |
# File 'lib/unitmanager/calculator.rb', line 57 def add_conversion(params) params.each {|source, target| begin @conversions << exp { target / source } @conversions << exp { source / target } rescue raise "Unit must be defined before used in conversion" end } end |
#add_unit(params) ⇒ Object
40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 |
# File 'lib/unitmanager/calculator.rb', line 40 def add_unit(params) raise "Unit symbol is required" unless (unit_sym = params[:unit]) raise "Unit with symbol: #{unit_sym.to_s} already defined" if @units[unit_sym] if (based_on_sym = params[:based_on]) raise "Invalid configuration. " + "Based_on unit must be defined before used." unless (based_on = @units[based_on_sym]) end @units[unit_sym] = Unit::SimpleUnit.new({ :unit => unit_sym, :based_on => based_on, :coefficient => params[:coefficient] || 1.0 }) end |
#exp(return_as = nil) ⇒ Object
31 32 33 34 35 36 37 38 |
# File 'lib/unitmanager/calculator.rb', line 31 def exp (return_as = nil) operand = yield self raise "Operand is not Quantifiable" unless quantifiable?(operand) convert_to(operand.to_quantity(self), result_unit(return_as)) end |
#perform_operation(first_operand, second_operand, operation) ⇒ Object
19 20 21 22 23 24 25 26 27 28 29 |
# File 'lib/unitmanager/calculator.rb', line 19 def perform_operation(first_operand, second_operand, operation) result = case operation when :+ then add(first_operand, second_operand) when :- then subtract(first_operand, second_operand) when :* then multiply(first_operand, second_operand) when :/ then divide(first_operand, second_operand) else raise "Operation #{operation.to_s} is not supported" end return result end |