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// Scilab ( http://www.scilab.org/ ) - This file is part of Scilab
// Copyright (C) INRIA - F.D
//
// This file must be used under the terms of the CeCILL.
// This source file is licensed as described in the file COPYING, which
// you should have received as part of this distribution.  The terms
// are also available at
// http://www.cecill.info/licences/Licence_CeCILL_V2.1-en.txt

function Tn=chepol(n,var)
    //Chebychev polynomial
    //  n   :Polynomial order
    //  var :Polynomial variable (character string)
    //  Tn  :Polynomial in var
    //
    //!
    if n==0 then
        Tn=poly(1,var,"coeff"),
    elseif n==1 then
        Tn=poly(0,var);
    else
        T0=poly(1,var,"coeff");
        T1=poly(0,var)
        for k=2:n
            Tn=2*poly(0,var)*T1-T0
            [T1,T0]=(Tn,T1);
        end
    end

endfunction