Functions are conventionally defined in HyperMath with the function keyword as follows:

    function function_name (args)

    body

    end

The following example shows a simple function called "foo" that receives a single argument and returns twice its value (in the command window, it needs to defined on a single line as shown below):

      > function foo(n)

        return n*2

        end

      > print(foo(7))

      14

There is also a format similar to C-style:

  function function_name (args)

  {

  body

  }

Multiple input arguments are separated by commas, for example the function foo(n,m).  A variable number of arguments can also be passed.  See Variable Number  of Arguments for more information.  There is no need to specify the number of returns, however.