function [mag, phase, freq] = bode2(num,den,w);
%[mag, phase, freq] = bode2(num,den,w);
%
%'bode2' is similar to the built in 'bode' function, except
%that it always plots the magnitude and phase plots regardless
%of whether or not left hand (output) arguments are specified.
%Also, 'bode2' displays (1) frequency, (2) log10(frequency), 
%(3) magnitude, (4) log10(magnitude), and (5) phase, tabulated 
%together in 5 columns.  Again, this is shown regardless of the 
%specified output arguments.
%
%As with the 'bode' function, if no frequency vector 'w' is 
%specified, the frequency range will be selected automatically
%and the frequency vector will contain 20+ points spaced
%logarithmically within that range.  If a third left hand (output)
%argument (e.g. 'freq') is specified, this frequency vector will be 
%returned by 'bode2'.
%
%The maximum number of data points displayed is 50 (since 50 lines 
%will fit easily within a long MatLab window).  If numerical data is
%scrolling off the top of your MatLab window, increase the window
%size.  If your frequency vector is longer than 50 points, the 50 
%displayed points will be evenly spaced over the full frequency range.
% 
%EXAMPLES:
%
%    >>bode2(num,den)     :bode plot and bode data display, 
%                          frequencies selected automatically
%    >>bode2(num,den,w)   :bode plot and bode data display,
%                          user specified frequencies in 'w'
%    >>[mag,phase,w] = bode2(num,den)
%                         :bode plot and bode data display,
%                          frequencies selected automatically
%                          magnitude, phase, and frequency
%                          vectors returned in [mag, phase, w]
%    >>[mag,phase] = bode2(num,den,w)
%                         :bode plot and bode data display,
%                          user specified frequencies in 'w'
%                          magnitude and phase at frequencies
%                          'w' returned in [mag, phase]                        
%  
%
%See also BODE, FBODE, LOGSPACE, LOGLOG, SEMILOGX, MARGIN, NICHOLS,
%and NYQUIST.

%This script was written by Keoki Jackson in June 1994 for the use of
%6.302/16.060 students.  If you find it useful, great!  If you have 
%any problems, go bother the current TA.

disp_num = 50;  %number of points to display

if nargin==2
	[m,p,w] = bode(num,den);
	bode(num,den);
elseif nargin==3
	[m,p] = bode(num,den,w);
	bode(num,den,w);
else
	disp('Number of input arguments must be 2 or 3');
	error('Usage:  [mag,phase,freq] = bode2(num,den,w)');
end

n = size(w);
if n(2)>n(1)
	w = w';
end  %if

disp(' ')
disp('      Freq log(Freq)       Mag  log(Mag)     Phase')
n = length(w);
if n<disp_num
	disp_num=n;
end  %if
ind = round(linspace(1,n,disp_num));
[w(ind) log10(w(ind)) m(ind) log10(m(ind)) p(ind)]

if nargout>=2
	mag=m; phase=p;
end  %if

if nargout==3
	freq=w;
end  %if