You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: iszero.m
    path of file: ./repos/chebfun/@chebtech
    
    the code of the file until where you have to start completion: function out = iszero(f)
%ISZERO    True for zero CHEBTECH objects.
%   ISZERO(F) returns logical TRUE is F.COEFFS has only zero entries and logical

    
function out = iszero(f)
%ISZERO    True for zero CHEBTECH objects.
%   ISZERO(F) returns logical TRUE is F.COEFFS has only zero entries and logical
%   FALSE otherwise.

% Copyright 2017 by The University of Oxford and The Chebfun Developers. 
% See http://www.chebfun.org/ for Chebfun information.

out = ~any(f.coeffs, 1);

if ( any(out) )
    % We need this as any(NaN) = 0, which will pass the test above.
    out = out & ~any(isnan(f.coeffs), 1);
    return
end