function [Wout, Vout] = dwtjm(Vin, h, g, j)% dwtjm -- Calculate jth level DWT coefficients (MATLAB implementation).%%****f* wmtsa.dwt/dwtjm%% NAME%   dwtjm -- Calculate jth level DWT coefficients (MATLAB implementation).%% USAGE%   [Wout, Vout] = dwtjm(Vin, h, g, j)%% INPUTS%   * Vin         -- Input series for j-1 level (i.e. DWT scaling coefficients) %   * h           -- DWT wavelet filter coefficients.%   * g           -- DWT scaling filter coefficients.%   * j           -- level (index) of scale.%% OUTPUTS%   * Wout        -- DWT wavelet coefficients for jth scale.%   * Vout        -- DWT scaling coefficients for jth scale.%%% SIDE EFFECTS%%% DESCRIPTION%   dwtjm is an implementation in MATLAB code of the DWT transform for %   the jth level, and is included in the toolkit for illustrative purposes %   to demonstrate the pyramid algothrim.%%   For speed considerations, the dwt function uses the C implementation of %   the DWT transform, modwtj, which linked in as a MEX function.%% EXAMPLE%   X = wmtsa_data('ecg');%   wtf = dwt_filter('haar');%   % Compute the j = 1 level coefficients for ECG time series.%   j = 1;%   [Wout, Vout] = dwtjm(X, h, g, j);%% NOTES%%% BUGS%%% TODO%%% ALGORITHM%   See page 100-101 of WMTSA for DWT pyramid algorithm.%% REFERENCES%%% SEE ALSO%   dwtj, dwt, dwt_filter%% TOOLBOX%   wmtsa%% CATEGORY%   dwt%% AUTHOR%   Charlie Cornish%% CREATION DATE%   2005-Sep-03%% COPYRIGHT%   (c) 2005 Charles R. Cornish%% MATLAB VERSION%   7.0%% CREDITS%%% REVISION%   $Revision: 612 $%%***%   $Id: dwtjm.m 612 2005-10-28 21:42:24Z ccornish $%% Set Defaults  usage_str = ['[Wout, Vout] = ', mfilename, '(Vin, h, g, j)'];  %% Check arguments.error(nargerr(mfilename, nargin, [4:4], nargout, [0:3], 1, usage_str, 'struct'));M = length(Vin);L = length(h);Wout = repmat(NaN, [M/2, 1]);Vout = repmat(NaN, [M/2, 1]);for (t = 1:M/2)  u = 2*t;  Wout(t) = h(1) * Vin(u);  Vout(t) = g(1) * Vin(u);  for (n = 2:L)    u = u - 1;    if (u < 1)      u = M;    end    Wout(t) = Wout(t) + h(n) * Vin(u);    Vout(t) = Vout(t) + g(n) * Vin(u);  endendreturn