## COS Trigonometric Cosine Function

Section: Mathematical Functions

### Usage

Computes the`cos`

function for its argument. The general
syntax for its use is
y = cos(x)

where `x`

is an `n`

-dimensional array of numerical type.
Integer types are promoted to the `double`

type prior to
calculation of the `cos`

function. Output `y`

is of the
same size and type as the input `x`

, (unless `x`

is an
integer, in which case `y`

is a `double`

type).

### Function Internals

Mathematically, the`cos`

function is defined for all real
valued arguments `x`

by the infinite summation

For complex valued arguments `z`

, the cosine is computed via

### Example

The following piece of code plots the real-valued`cos(2 pi x)`

function over one period of `[0,1]`

:
--> x = linspace(0,1); --> plot(x,cos(2*pi*x))