chepol
======

Chebychev polynomial



Calling Sequence
~~~~~~~~~~~~~~~~


::

    [Tn]=chepol(n,var)




Arguments
~~~~~~~~~

:n integer : polynomial order
: :var string : polynomial variable
: :Tn polynomial in the variable `var`
:



Description
~~~~~~~~~~~

Recursive implementation of Chebychev polynomial.
`Tn=2*poly(0,var)*chepol(n-1,var)-chepol(n-2,var)` with `T0=1` and
`T1=poly(0,var)`.



Examples
~~~~~~~~


::

    chepol(4,'x')