Class: Subtraction

Inherits:
Equation show all
Defined in:
lib/symcalc.rb

Overview

Implements the subtraction operation in SymCalc

Instance Method Summary collapse

Methods inherited from Equation

#*, #**, #+, #-, #/, #coerce, #derivative, #eval, #inspect, #simplify, #sub, #to_s

Constructor Details

#initialize(lside, rside) ⇒ Subtraction 



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# File 'lib/symcalc.rb', line 407

def initialize lside, rside
  @lside = lside
  @rside = rside
end

Instance Method Details

#__derivative__(variable: nil) ⇒ Object 



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# File 'lib/symcalc.rb', line 420

def __derivative__ variable: nil
  return @lside.derivative(variable: variable) - @rside.derivative(variable: variable)
end

#__eval__(var_hash) ⇒ Object 



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# File 'lib/symcalc.rb', line 416

def __eval__ var_hash
  return @lside.eval(var_hash) - @rside.eval(var_hash)
end

#__get_m_elements__(el_hash) ⇒ Object 



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# File 'lib/symcalc.rb', line 424

def __get_m_elements__ el_hash
  if el_hash.keys.include? self
    el_hash[self] += 1
  else
    el_hash[self] = 1
  end
  return el_hash
end

#__simplify__ ⇒ Object 



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# File 'lib/symcalc.rb', line 433

def __simplify__
  @lside = @lside.__simplify__
  @rside = @rside.__simplify__
  
  if (@lside.is_a? EquationValue) && (@rside.is_a? EquationValue)
    return EquationValue.new((@lside - @rside).eval(Hash.new))
  elsif @rside == EquationValue.new(0)
    return @lside
  elsif @lside == EquationValue.new(0)
    return -1 * @rside
  elsif @lside == @rside
    return EquationValue.new(0)
  else
    return self
  end
end

#__sub__(original, replacement) ⇒ Object 



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# File 'lib/symcalc.rb', line 454

def __sub__ original, replacement
  return to_equation(replacement) if self == to_equation(original)
  return @lside.__sub__(original, replacement) - @rside.__sub__(original, replacement)
end

#all_variables ⇒ Object 



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# File 'lib/symcalc.rb', line 450

def all_variables
  return (@lside.all_variables + @rside.all_variables).uniq
end

#display ⇒ Object 



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# File 'lib/symcalc.rb', line 412

def display
  return "(#{@lside.display}) - (#{@rside.display})"
end