%% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

%%            Output Info about this m-file

fprintf('\n***********************************************************\n');

fprintf('        <DSP using MATLAB> Problem 6.22 \n\n');

banner();

%% ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

%format long;

format short;

fprintf('\n FIR filter DIRECT-form:     \n');

h = [1, -4, 6.4, -5.12, 2.048, -0.32768]; 

b = h

a = 1.0

fprintf('\nConvert DIRECT-form to PARALLEL-form :     \n');

[C, Bp, Ap] = dir2par(b, a)

if size(C)==0

  C = 0;

end

fprintf('\nConvert DIRECT-form to CASCADE-form :     \n');

[b0, Bc, Ac] = dir2cas(b, a) 

fprintf('\nConvert TF-form to SOS-form :     \n');

[sos, g] = tf2sos(b, a)

fprintf('\nConvert DIRECT-form to FREQUENCY-SAMPLE-form 1 :     \n');

[Cfs, Bfs, Afs] = dir2fs(b) 

fprintf('\nConvert DIRECT-form to FREQUENCY-SAMPLE-form 2 :     \n');

r = 0.99;

[Cfs_r, Bfs_r, Afs_r, rM] = dir2fs_r(b, r) 

% ----------------------------------------------------------

% NOTE: linear-phase can not use LATTICE-form

% ----------------------------------------------------------

fprintf('\nConvert DIRECT-form to All-Zero LATTICE-form :     \n');

[Klc] = dir2latc(b) 

% -----------------------------------------

%     START check

% -----------------------------------------

n = [0:7];

delta = impseq(0, 0, 7)

%format long

format  short

hcas = casfiltr(b0, Bc, Ac, delta)

hltc = latcfilt(Klc, delta)

%hladr = ladrfilt(Klr, Clr, delta)

hdir = filter(b, a, delta)

% -------------------------------------------

%       END check

% -------------------------------------------

% +++++++++++++++++++++++++++++++++++++++++++++++++

%             5 1st-order section CASCADE-form

% +++++++++++++++++++++++++++++++++++++++++++++++++

broots = roots(b)

L = length(broots)

B1 = ones(L, 2);

fprintf('\nConvert DIRECT-form to %d 1st-order section :     \n', L);

for i = 1:1:L

	B1(i,:) = poly( broots(i) );

end

B1

% +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

%      CASCADE-form of 1 1st-order section and 2 2nd-order section

% +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

fprintf('\nConvert DIRECT-form to One 1st-order and Two 2nd-order section:     \n');

B2 = poly( [broots(1), broots(2)] )

B3 = poly( [broots(3), broots(4)] )

B4 = poly( broots(5) )

% +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

%      CASCADE-form of 1 2nd-order section and 1 3rd-order section

% +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

fprintf('\nConvert DIRECT-form to One 2nd-order and One 3rd-order section:     \n');

B5 = poly( [broots(1), broots(2)] )

B6 = poly( [broots(3), broots(4), broots(5)] )