function [dp] = dict( dp, state )
% function [dp] = dict( dp, state )
%
% Part of my kernel dictionary implementation.  state is a column
% vector, which may or may not be added to the dictionary, based on
% whether or not its features are almost-linearly-dependent of
% other points in the dictionary.
%
% INPUT:
%   dp - data structure representing problem setup, returned from
%        dict_init or subsequent calls to this function.
%   state - a new data point
%
% OUTPUT:
%   dp - an updated data structure.
%
%

  m = size( dp.Dict, 2 ); % number of entries

  ktt = feval( dp.kfunc, state, state, dp.kparam );

  ktwid = feval( dp.kfunc, dp.Dict, state, dp.kparam );

  at = dp.Kinv * ktwid;
  dt = ktt - ktwid' * at;

  dp.addedFlag = 0;   

  if ( dt > dp.thresh )
    % Not ALD; add to dictionary
    dp.Dict = [ dp.Dict , state ];
    dp.K = [ dp.K, ktwid; ktwid', ktt ];
    dp.Kinv = (1/dt) * [ dt*(dp.Kinv) + at*at', -at; -at', 1 ];

    dp.addedFlag = 1;
  end;

  dp.at = at;
  dp.dt = dt;
  dp.ktwid = ktwid;
  kp.ktt = ktt;

return;