#### 1.3.5.1 A Sample Function Description

In a function description, the name of the function being described appears first. It is followed on the same line by a list of parameters. The names used for the parameters are also used in the body of the description.

After all of the calling forms have been enumerated, the next line is a concise one-sentence summary of the function.

After the summary there may be documentation on the inputs and outputs, examples of function usage, notes about the algorithm used, and references to related functions.

Here is a description of an imaginary function `foo`:

foo (x)
foo (x, y)
foo (x, y, …)

  Subtract x from y, then add any remaining arguments to the result.

  The input x must be a numeric scalar, vector, or array.

  The optional input y defaults to 19 if it is not supplied.

  Example:

      foo (1, [3, 5], 3, 9)
           ⇒ [ 14, 16 ]
      foo (5)
           ⇒ 14

  More generally,

      foo (w, x, y, …)
      ≡
      x - w + y + …

  See also: bar

Any parameter whose name contains the name of a type (e.g., integer or matrix) is expected to be of that type. Parameters named object may be of any type. Parameters with other sorts of names (e.g., new_file) are discussed specifically in the description of the function. In some sections, features common to parameters of several functions are described at the beginning.