function t=atk(tk)
% atk	- Converts a given temperature given in K to the unit Tdeg
% function t=atk(tk)
% Argument List: tk is the temp. in K.
% The function returns the temp in Tdeg.
% See also AT
% Ex. Tdeg='C';
%     atk(298.15)
%    will give 25.
%revised help by TYLC

global Tdeg
if Tdeg=='K'
    t=tk;
elseif Tdeg=='C'
    t=tk-273.15;
elseif Tdeg=='F'
    t=(1.8*tk)-459.67;
elseif Tdeg=='R'
    t=1.8*tk;
else
    disp('Error in Tdeg. Should be K, C, F or R.')
end
