resampling(on_off)

function resampling(on_off)
%RESAMPLING   CHEBFUN resample option
%
%   RESAMPLING ON forces the Chebfun constructor to sample a function at
%   all Chebyshev points as it adapts the number of nodes needed for an
%   accurate representation.  This option is recommended when working with
%   chebops or if the values of the function depend on the number of
%   points.
%
%   RESAMPLING OFF allows the constructor to sample only at new nodes
%   whenever the number of nodes is doubled. This option is recommended
%   when the evaluations are time consuming.
%
%   RESAMPLING is OFF by default, by itself, displays the current splitting
%   state,

%   Copyright 2011 by The University of Oxford and The Chebfun Developers. 
%   See http://www.maths.ox.ac.uk/chebfun/ for Chebfun information.

if nargin==0 
    switch chebfunpref('resampling')
        case 1 
            disp('RESAMPLING is currently ON')
        case 0
            disp('RESAMPLING is currently OFF')
    end
else
    if strcmpi(on_off, 'on')
        chebfunpref('resampling',true)
    elseif strcmpi(on_off, 'off') 
        chebfunpref('resampling',false)
    else
        error('CHEBFUN:resampling:UnknownOption',...
          'Unknown resampling option: only ON and OFF are valid options.')
    end
end