line source
+ − % TOMFIR approximates a pole/zero model with an FIR filter.
+ − %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+ − %
+ − % DESCRIPTION: TOMFIR approximates a pole/zero model with an FIR filter.
+ − % The response of the pzmodel is computed using pzmodel/resp with
+ − % the additional input parameter of param('f1', 0). The final
+ − % frequency in the response is set automatically from the
+ − % pzmodel/resp function if not specified as an input. This upper
+ − % frequency is then taken as the Nyquist frequency and the
+ − % sample rate of the corresponding fsdata AO is set accordingly.
+ − % The function then calls mfir() with the new fsdata AO as input.
+ − % The result is an FIR filter designed to have a magnitude response
+ − % equal to the magnitude response of the pole/zero model. The filter
+ − % has linear phase and the phase of the pzmodel is ignored.
+ − %
+ − % CALL: f = tomfir(pzm)
+ − % f = tomfir(pzm, plist)
+ − %
+ − % <a href="matlab:utils.helper.displayMethodInfo('pzmodel', 'tomfir')">Parameters Description</a>
+ − %
+ − % VERSION: $Id: tomfir.m,v 1.18 2011/04/08 08:56:32 hewitson Exp $
+ − %
+ − %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+ −
+ − function varargout = tomfir(varargin)
+ −
+ − %%% Check if this is a call for parameters
+ − if utils.helper.isinfocall(varargin{:})
+ − varargout{1} = getInfo(varargin{3});
+ − return
+ − end
+ −
+ − % Check output arguments number
+ − if nargout == 0
+ − error('### pzmodel/tomfir cannot be used as a modifier. Please give an output variable.');
+ − end
+ −
+ − % Collect input variable names
+ − in_names = cell(size(varargin));
+ − for ii = 1:nargin,in_names{ii} = inputname(ii);end
+ −
+ − % Collect all AOs
+ − [pzms, pzm_invars] = utils.helper.collect_objects(varargin(:), 'pzmodel', in_names);
+ − pls = utils.helper.collect_objects(varargin(:), 'plist');
+ −
+ − % Store inhists to suppress intermediate history steps
+ − inhists = [pzms(:).hist];
+ −
+ − % Get default parameters
+ − pl = parse(pls, getDefaultPlist);
+ −
+ − % Decide on a deep copy or a modify
+ − pzms = copy(pzms, nargout);
+ −
+ − % check design parameters
+ − fs = find(pl, 'fs');
+ − f1 = find(pl, 'f1');
+ − f2 = find(pl, 'f2');
+ − nf = find(pl, 'nf');
+ − f2 = fs/2;
+ −
+ − r = resp(pzms, plist('f1', f1, 'f2', f2, 'nf', nf, 'scale', 'lin'));
+ −
+ − % Set fs
+ − r.setFs(fs);
+ −
+ − % compute filter
+ − for kk = 1:numel(r)
+ − % throws a warning if the model has a delay
+ − if(pzms(kk).delay~=0)
+ − disp('!!! PZmodel delay is not used in the discretization')
+ − end
+ − % Compute mfir filter
+ − f(kk) = mfir(r(kk));
+ − f(kk).addHistory(getInfo, pl, pzm_invars(kk), inhists(kk));
+ − end
+ −
+ − % Reshape the output to the shape of the input
+ − f = reshape(f, size(r));
+ −
+ − % Set output
+ − if nargout == numel(f)
+ − % List of outputs
+ − for ii = 1:numel(f)
+ − varargout{ii} = f(ii);
+ − end
+ − else
+ − % Single output
+ − varargout{1} = f;
+ − end
+ −
+ − end
+ −
+ − %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+ − % Local Functions %
+ − %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+ −
+ − %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+ − %
+ − % FUNCTION: getInfo
+ − %
+ − % DESCRIPTION: Get Info Object
+ − %
+ − % HISTORY: 11-07-07 M Hewitson
+ − % Creation.
+ − %
+ − %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+ −
+ − function ii = getInfo(varargin)
+ − if nargin == 1 && strcmpi(varargin{1}, 'None')
+ − sets = {};
+ − pl = [];
+ − else
+ − sets = {'Default'};
+ − pl = getDefaultPlist;
+ − end
+ − % Build info object
+ − ii = minfo(mfilename, 'pzmodel', 'ltpda', utils.const.categories.op, '$Id: tomfir.m,v 1.18 2011/04/08 08:56:32 hewitson Exp $', sets, pl);
+ − ii.setModifier(false);
+ − end
+ −
+ − %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+ − %
+ − % FUNCTION: getDefaultPlist
+ − %
+ − % DESCRIPTION: Get Default Plist
+ − %
+ − % HISTORY: 11-07-07 M Hewitson
+ − % Creation.
+ − %
+ − %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+ −
+ − function plout = getDefaultPlist()
+ − persistent pl;
+ − if exist('pl', 'var')==0 || isempty(pl)
+ − pl = buildplist();
+ − end
+ − plout = pl;
+ − end
+ −
+ − function plo = buildplist()
+ − fs = 10;
+ − f2 = fs/2;
+ −
+ − plo = plist();
+ −
+ − % FS
+ − p = param({'fs', 'Frequency of the fir filter.'}, paramValue.DOUBLE_VALUE(fs));
+ − plo.append(p);
+ −
+ − % F1
+ − p = param({'f1','Start frequency.'}, paramValue.DOUBLE_VALUE(0));
+ − plo.append(p);
+ −
+ − % F2
+ − p = param({'f2','Stop frequency.'}, paramValue.DOUBLE_VALUE(f2));
+ − plo.append(p);
+ −
+ − % Nf
+ − p = param({'nf','Number of evaluation frequencies.'}, paramValue.DOUBLE_VALUE(1000));
+ − plo.append(p);
+ −
+ − % Scale
+ − p = param({'scale',['Spacing of frequencies:<ul>', ...
+ − '<li>''lin'' - Linear scale.</li>', ...
+ − '<li>''log'' - Logarithmic scale.</li></ul>']}, {1, {'lin', 'log'} paramValue.SINGLE});
+ − plo.append(p);
+ −
+ − end
+ −