Class: Variable

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

Overview

Implements the Variable class

Instance Method Summary collapse

Methods inherited from Equation

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

Constructor Details

#initialize(name, fixed_value = nil) ⇒ Variable

Create a new symbolic variable with a custom display name, and an optional fixed value Accepts the display name and an optional fixed_value Fixed_value works in the cases of evaluating the function

Example: x = Variable.new “x”, 5 fx = x ** 2 fx.eval # => 25



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# File 'lib/symcalc.rb', line 304

def initialize name, fixed_value = nil
  @name = name
  @fixed_value = fixed_value
end

Instance Method Details

#__derivative__(variable: nil) ⇒ Object 



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# File 'lib/symcalc.rb', line 324

def __derivative__ variable: nil
  if variable == nil || variable == self
    return EquationValue.new 1
  else
    return to_equation(0)
  end
end

#__eval__(var_hash) ⇒ Object 



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# File 'lib/symcalc.rb', line 313

def __eval__ var_hash
  if @fixed_value
    return @fixed_value
  elsif var_hash.keys.include?(@name.to_sym) or var_hash.keys.include?(@name.to_s)
    return (var_hash[@name.to_sym] or var_hash[@name.to_s])
  else
    raise "No value provided for #{@name.to_s} in eval"
    # return nil
  end
end

#__get_m_elements__(var_hash) ⇒ Object 



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# File 'lib/symcalc.rb', line 332

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

#all_variables ⇒ Object 



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# File 'lib/symcalc.rb', line 341

def all_variables
  return [self]
end

#display ⇒ Object 



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# File 'lib/symcalc.rb', line 309

def display
  return @name
end