Add a useful package (from Source forge) for octave

[CreaPhase.git] / octave_packages / signal-1.1.3 / tfestimate.m

diff --git a/octave_packages/signal-1.1.3/tfestimate.m b/octave_packages/signal-1.1.3/tfestimate.m
new file mode 100644 (file)
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+++ b/octave_packages/signal-1.1.3/tfestimate.m
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+%% Copyright (C) 2006 Peter V. Lanspeary <pvl@mecheng.adelaide.edu.au>
+%%
+%% This program is free software; you can redistribute it and/or modify it under
+%% the terms of the GNU General Public License as published by the Free Software
+%% Foundation; either version 3 of the License, or (at your option) any later
+%% version.
+%%
+%% This program is distributed in the hope that it will be useful, but WITHOUT
+%% ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+%% FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
+%% details.
+%%
+%% You should have received a copy of the GNU General Public License along with
+%% this program; if not, see <http://www.gnu.org/licenses/>.
+
+%% Usage:
+%%   [Pxx,freq]=tfestimate(x,y,Nfft,Fs,window,overlap,range,plot_type,detrend)
+%%
+%%     Estimate transfer function of system with input "x" and output "y".
+%%     Use the Welch (1967) periodogram/FFT method.
+%%     See "help pwelch" for description of arguments, hints and references.
+
+function [varargout] = tfestimate(varargin)
+  %%
+  %% Check fixed argument
+  if ( nargin<2 )
+    error( 'tfestimate: Need at least 2 args. Use help tfestimate' );
+  end
+  nvarargin = length(varargin);
+  %% remove any pwelch RESULT args and add 'cross'
+  for iarg=1:nvarargin
+    arg = varargin{iarg};
+    if ( ~isempty(arg) && ischar(arg) && ( strcmp(arg,'power') || ...
+           strcmp(arg,'cross') || strcmp(arg,'trans') || ...
+           strcmp(arg,'coher') || strcmp(arg,'ypower') ))
+      varargin{iarg} = [];
+    end
+  end
+  varargin{nvarargin+1} = 'trans';
+  %%
+  if ( nargout==0 )
+    pwelch(varargin{:});
+  elseif ( nargout==1 )
+    Pxx = pwelch(varargin{:});
+    varargout{1} = Pxx;
+  elseif ( nargout>=2 )
+    [Pxx,f] = pwelch(varargin{:});
+    varargout{1} = Pxx;
+    varargout{2} = f;
+  end
+end