Expression

Mathematical expression calculator. Use this gem as a calculator.

Installation

Add this line to your application’s Gemfile:

gem 'Expression'

And then execute:

$ bundle

Or install it yourself as:

$ gem install Expression

Usage

Initialize a variable:

expr = MathExpression.new

and then it is just:

expr.eval(Your_expression)

supported functions:

• Basic arithmetics

• exponentiation

  expr.eval('6^3')
  

• factorial

  expr.eval('5!')
  

• modulo operation:

  expr.eval('9 % 5')
  

• floating numbers

• trigonometric identities (cos, sin, tan, cosh, sinh, tanh) and their inverses (by prefixing any of them by ‘arc’ e.g: arccos)

• exponential: (exp(x) return e to the power of x)

  expr.eval('exp(2)')
  

• logarithm:

  • General: you can use log{base}(number) e.g:

    expr.eval('log2(12)')
    

returns the result of calling log of base 2 for the number 12.

expr.eval('log20(123)')

etc

• when you omit the base, the default is base 10 i.e:

  expr.eval('log(23)')
  

is the same as

expr.eval('log10(23)')

• for base ‘e’ you can use natural logarithm:

  expr.eval('ln(21)')
  

• root functions:

  • square root:

    expr.eval('sqrt(21)')
    

  • for other bases use root{base}(number):

    expr.eval('root3(12)')
    

Contributing

1. Fork it

2. Create your feature branch (‘git checkout -b my-new-feature`)

3. Commit your changes (‘git commit -am ’Add some feature’‘)

4. Push to the branch (‘git push origin my-new-feature`)

5. Create new Pull Request