function s = Output_string(k, t, fun, dt, norm_grad, max_dx)
% s = Output_string(k, t, fun, dt, norm_grad, max_dx)
% 
% Output_string creates the screen output for an optimization algorithm.
%
% See also: L_BFGS
%
% 2013-07-25 --------------------------------------------------------------
% 
% Matthias J. Ehrhardt
% CMIC, University College London, UK
% 
% matthias.ehrhardt.11@ucl.ac.uk
% 
% -------------------------------------------------------------------------
    
    s = sprintf('   step %2i: time=%5.1fs, fun=%5.3e, dt=%5.2e, |grad|=%3.1e, max|dx|=%3.1e', k, t, fun, dt, norm_grad, max_dx);
end