function freqplot(fdata, ydata, symbol, ttl, xlab, ylab)
% FREQPLOT - Plot a function of frequency:
%
%   freqplot(fdata[,ydata[,symbol[,title[,xlab[,ylab]]]]])
%
%   This version is most compatible with Octave.
%   In Matlab, the title and axis labels may be lost.
%   For Matlab compatibility, move the plot() command
%   before title() and axis label commands.

  if nargin<6, ylab=''; end
  if nargin<5, xlab='Frequency'; end
  if nargin<4, ttl=''; end
  if nargin<3, symbol=''; end
  if nargin<2, ydata=fdata; fdata=0:length(ydata)-1; end

  if ttl, title(ttl); end
  if length(ylab)>0, ylabel(ylab); end
  if length(xlab)>0, xlabel(xlab); end
  grid('on');
  plot(fdata,ydata,symbol);

function freqplot(fdata, ydata, symbol, ttl, xlab, ylab)
% FREQPLOT - Plot a function of time, Matlab version.

  if nargin<6, ylab=''; end
  if nargin<5, xlab='Frequency (Hz)'; end
  if nargin<4, ttl=''; end
  if nargin<3, symbol=''; end
  if nargin<2, fdata=0:length(ydata)-1; end

  plot(fdata,ydata,symbol); grid;
  if ttl, title(ttl); end
  if ylab, ylabel(ylab); end
  xlabel(xlab);