Mercurial > hg > ltpda
diff m-toolbox/classes/@ao/mcmc_td.m @ 0:f0afece42f48
Import.
author | Daniele Nicolodi <nicolodi@science.unitn.it> |
---|---|
date | Wed, 23 Nov 2011 19:22:13 +0100 |
parents | |
children |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/m-toolbox/classes/@ao/mcmc_td.m Wed Nov 23 19:22:13 2011 +0100 @@ -0,0 +1,275 @@ +% MCMC_TD estimates paramters using a Monte Carlo Markov Chain. +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +% +% DESCRIPTION: MCMC estimate the parameters of a given model given +% inputs, outputs and noise using a Metropolis algorithm. +% +% +% CALL: b = mcmc(out,pl) +% +% INPUTS: +% out - analysis objects with measured outputs +% pl - parameter list +% +% OUTPUTS: b - pest object contatining estimate information +% +% <a href="matlab:utils.helper.displayMethodInfo('ao', 'mcmc_td')">Parameters Description</a> +% +% VERSION: $Id: mcmc_td.m,v 1.6 2011/04/08 08:56:12 hewitson Exp $ +% +% References: "Catching supermassive black holes binaries without a net" +% N.J. Cornish, E.K. Porter, Phys.Rev.D 75, 021301, 2007 +% +% TODO: multiple chain option not implemented yet +% metropolis/hastings not implemented +% empty initial values not implemented +% +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% + +function varargout = mcmc_td(varargin) + + % Check if this is a call for parameters + if utils.helper.isinfocall(varargin{:}) + varargout{1} = getInfo(varargin{3}); + return + end + + import utils.const.* + utils.helper.msg(msg.PROC3, 'running %s/%s', mfilename('class'), mfilename); + + % Method can not be used as a modifier + if nargout == 0 + error('### metropolis2D 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 smodels and plists + [as, ao_invars] = utils.helper.collect_objects(varargin(:), 'ao', in_names); + pl = utils.helper.collect_objects(varargin(:), 'plist', in_names); + + % Decide on a deep copy or a modify + bs = copy(as, nargout); + + out = bs; + + + % Combine plists + pl = parse(pl, getDefaultPlist); + + + % Get parameters + N = find(pl, 'N'); + Tc = find(pl,'Tc'); + xi = find(pl,'heat'); + cvar = find(pl, 'cov'); + rng = find(pl,'range'); + search = find(pl,'search'); + simplex = find(pl,'simplex'); + x0 = find(pl,'x0'); + mdl = find(pl,'model'); + %nse = find(pl,'noise'); + jumps = find(pl,'jumps'); + parplot = find(pl,'plot'); + debug = find(pl,'debug'); + + in = find(pl,'Input'); + inNames = find(pl,'inNames'); + outNames = find(pl,'outNames'); + Noise = find(pl,'Noise'); + parnames = find(pl,'parnames'); + cutbefore = find(pl,'cutbefore'); + cutafter = find(pl,'cutafter'); + + % Check input parameters + if isempty(rng) + error('### Please define a search range ''range'''); + end + + if isempty(parnames) + error('### Please define the parameters ''parnames'''); + end + nparam = numel(parnames); + + + % Get range for parameters + for i = 1:nparam + range(:,i) = rng{i}; + end + + + + % do simplex + if simplex + if isempty(x0) + error('### Simplex needs a starting guess. Please input a ''x0''.'); + else + switch class(mdl) + case 'smodel' + %xo = fminsearch(@(x) utils.math.loglikehood(x,in,out,nse,mdl,param),xo,optimset('Display','iter')); + case 'ssm' + x0 = fminsearch(@(x)utils.math.loglikehood_ssm_td(x,in,out,parnames,mdl,inNames,outNames,Noise,'cutbefore',cutbefore,'cutafter',cutafter),x0,optimset('Display','iter')); + otherwise + error('### Model must be either from the ''smodel'' or the ''ssm'' class. Please check the inputs') + end + + for i = 1:numel(parnames) + fprintf('### Simplex estimate: %s = %d \n',parnames{i},x0(i)) + %save('parameters_simplex.txt','x0','-ASCII') + end + end + end + + % sample distribution + smpl = utils.math.mhsample_td(mdl,in,out,cvar,N,range,parnames,Tc,xi,x0,search,jumps,parplot,debug,inNames,outNames,Noise,cutbefore,cutafter); + + % statistics of the chain + if isempty(Tc) + initial =1; + else + initial = Tc(2)+1; + end + + mn = mean(smpl(initial:end,:)); + cv = cov(smpl(initial:end,:)); + + cr = utils.math.cov2corr(cv); + + % compute pdf + for i = 1:nparam + [count,bin] = hist(smpl(initial:end,i)); + end + + % create pest output + p = pest(mn); + p.setName('metropolis2D'); + p.setNames(parnames{:}); + % add statistical info + p.setCov(cv); + p.setCorr(cr); + p.setDy(sqrt(diag(cv))); % need to change if non-gaussian + p.setPdf([reshape(bin, 1, []), reshape(count, 1, [])]); % not yet able to store bins + p.setChain(smpl); + p.setModels(mdl); + % set history + p.addHistory(getInfo('None'), pl, [ao_invars(:)], [bs(:).hist mdl(:).hist]); + + % Set output + varargout{1} = p; + +end + + + +%-------------------------------------------------------------------------- +% Get Info Object +%-------------------------------------------------------------------------- +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, 'ao', 'ltpda', utils.const.categories.sigproc, '$Id: mcmc_td.m,v 1.6 2011/04/08 08:56:12 hewitson Exp $', sets, pl); +end + +%-------------------------------------------------------------------------- +% Get Default Plist +%-------------------------------------------------------------------------- +function plout = getDefaultPlist() + persistent pl; + if exist('pl', 'var')==0 || isempty(pl) + pl = buildplist(); + end + plout = pl; +end + +function pl = buildplist() + pl = plist(); + + % N + p = param({'N','number of samples of the chain.'}, paramValue.DOUBLE_VALUE(1000)); + pl.append(p); + + % Sigma + p = param({'cov','covariance of the gaussian jumping distribution.'}, paramValue.DOUBLE_VALUE(1e-4)); + pl.append(p); + + % Param + p = param({'parnames','A cell array of evaluated parameters.'}, paramValue.EMPTY_CELL); + pl.append(p); + + + % Model + p = param({'model','The model for the system, at the moment only ssm is supported'}, paramValue.EMPTY_STRING); + pl.append(p); + + % Search + p = param({'search','Set to true to use bigger jumps in parameter space during annealing and cool down.'}, paramValue.TRUE_FALSE); + pl.append(p); + + % Simplex + p = param({'simplex','Set to true to perform a simplex search to find the starting parameters of the MCMC chain.'}, paramValue.TRUE_FALSE); + pl.append(p); + + % heat + p = param({'heat','The heat index flattening likelihood surface during annealing.'}, paramValue.DOUBLE_VALUE(1)); + pl.append(p); + + % Tc + p = param({'Tc','An array of two values setting the initial and final value for the cooling down.'}, paramValue.EMPTY_STRING); + pl.append(p); + + % x0 + p = param({'x0','The proposed initial values.'}, paramValue.EMPTY_DOUBLE); + pl.append(p); + + % jumps + p = param({'jumps','An array of four numbers setting the rescaling of the covariance matrix during the search phase.',... + 'The first value is the one applied by default, the following thhree apply just when the chain sample is',... + 'mod(10), mod(25) and mod(100) respectively.'}, paramValue.EMPTY_DOUBLE); + pl.append(p); + + % plot + p = param({'plot','Select indexes of the parameters to be plotted.'}, paramValue.EMPTY_DOUBLE); + pl.append(p); + + % debug + p = param({'debug','Set to true to get debug information of the MCMC process.'}, paramValue.FALSE_TRUE); + pl.append(p); + + % Input + p = param({'Input','An array of analysis object containing the input signals'},paramValue.EMPTY_DOUBLE); + pl.append(p); + + % inNames + p = param({'inNames','Cell array of input port names'}, paramValue.EMPTY_CELL); + pl.append(p); + + % outNames + p = param({'outNames','Cell array of output port names'}, paramValue.EMPTY_CELL); + pl.append(p); + + + % Noise + p = param({'Noise','An array of analysis objects containg noise series'}, paramValue.EMPTY_DOUBLE); + pl.append(p); + + % cutbefore + p = param({'cutbefore','the data samples to cut at the starting of the series'}, paramValue.EMPTY_DOUBLE); + pl.append(p); + + % cutafter + p = param({'cutafter','the data samples to cut at the ending of the series'}, paramValue.EMPTY_DOUBLE); + pl.append(p); + + +end + + +