   initialize: (@opts={})->
     @ui_elements = @opts.ui_elements
 
+  # Number specifiers
   base10Digits: (opts={})->
     for num in [0..9]
       do (num)=>

      class: 'math-button other fraction'
    }, opts)

  lparen: (opts)->
    @button({
      value: '('
      class: 'math-button parentheses other'
    }, opts)

  rparen: (opts)->
    @button({
      value: ')'
      class: 'math-button parentheses other'
    }, opts)

  pi: (opts)->
    @button({
      value: 'pi'
      label: '&pi;'
      class: 'math-button pi other'
    }, opts)

  variables: (opts)->

        do (v)=>
          @button({
            value: "#{v.name}"
            class: 'math-button other variable'
            variable: v
          }, opts)
    variables
