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−% PPPLOT makes probability-probability plot
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−%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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−% 
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−% h = ppplot(y1,[],ops) Plot a probability-probability plot comparing with
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−% theoretical model.
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−% 
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−% h = cdfplot(y1,y2,ops) Plot a probability-probability plot comparing two
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−% empirical cdfs.
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−% 
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−% ops is a cell aray of options
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−%   - 'ProbDist' -> theoretical distribution. Available distributions are:
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−%     - 'Fdist' -> F cumulative distribution function. In this case the
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−%     parameter 'params' should be a vector with distribution degrees of
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−%     freedoms [dof1 dof2]
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−%     - 'Normdist' -> Normal cumulative distribution function. In this case
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−%     the parameter 'params' should be a vector with distribution mean and
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−%     standard deviation [mu sigma]
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−%     - 'Chi2dist' -> Chi square cumulative distribution function. In this
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−%     case the parameter 'params' should be a number indicating
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−%     distribution degrees of freedom
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−%   - 'params' -> Probability distribution parameters
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−%   - 'conflevel' -> requiered confidence for confidence bounds evaluation.
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−%   Default 0.95 (95%)
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−%   - 'FontSize' -> Font size for axis. Default 22
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−%   - 'LineWidth' -> line width. Default 2
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−%   - 'axis' -> set axis properties of the plot. refer to help axis for
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−%   further details
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−% 
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−% Luigi Ferraioli 11-02-2011
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−% 
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−% % $Id: ppplot.m,v 1.5 2011/03/15 17:16:27 luigi Exp $
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−%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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−function h = ppplot(y1,y2,ops)
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−  
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−  %%% check and set imput options
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−  % Default input struct
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−  defaultparams = struct('ProbDist','Fdist',...
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−    'params',[1 1],...
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−    'conflevel',0.95,...
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−    'FontSize',22,...
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−    'LineWidth',2,...
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−    'axis',[]);
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−  
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−  names = {'ProbDist','params','conflevel','FontSize','LineWidth','axis'};
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−  
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−  % collecting input and default params
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−  if nargin == 3
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−    if ~isempty(ops)
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−      for jj=1:length(names)
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−        if isfield(ops, names(jj))
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−          defaultparams.(names{1,jj}) = ops.(names{1,jj});
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−        end
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−      end
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−    end
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−  end
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−  
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−  pdist = defaultparams.ProbDist; % check theoretical distribution
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−  dof = defaultparams.params; % distribution parameters
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−  conf = defaultparams.conflevel; % confidence level for confidence bounds calculation
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−  if conf>1
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−    conf = conf/100;
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−  end
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−  fontsize = defaultparams.FontSize;
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−  lwidth = defaultparams.LineWidth;
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−  axvect = defaultparams.axis;
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−
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−  
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−  %%% check data input
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−  if isempty(y2) % do theoretical comparison
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−    % get empirical distribution for input data
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−    [ep,ex]=utils.math.ecdf(y1);
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−    % switch between input theoretical distributions
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−    switch lower(pdist)
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−      case 'fdist'
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−        % get theoretical probabilities corresponding to empirical quantiles
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−        tp = utils.math.Fcdf(ex,dof(1),dof(2));
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−      case 'normdist'
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−        tp = utils.math.Normcdf(ex,dof(1),dof(2));
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−      case 'chi2dist'
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−        tp = utils.math.Chi2cdf(ex,dof(1));
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−    end
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−    % get confidence levels with Kolmogorow - Smirnov test
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−    alp = (1-conf)/2;
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−    cVal = utils.math.SKcriticalvalues(numel(ex),numel(ex),alp);
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−    % get upper and lower bounds for x
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−    pup = CD+cVal;
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−    plw = CD-cVal;
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−    
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−    figure
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−    h1 = plot(tp,ep);
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−    grid on
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−    hold on
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−    lnx = [min(tp) max(tp(1:end-1))];
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−    lny = [min(tp) max(tp(1:end-1))];
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−    h2 = line(lnx,lny,'Color','k');
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−    h3 = plot(tp,pup,'b--');
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−    h4 = plot(tp,plw,'b--');
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−    xlabel('Theoretical Probability','FontSize',fontsize);
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−    ylabel('Sample Probability','FontSize',fontsize);
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−    set(h1(1), 'Color','r', 'LineStyle','-','LineWidth',lwidth);
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−    set(h2(1), 'Color','k', 'LineStyle','--','LineWidth',lwidth);
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−    set(h3(1), 'Color','b', 'LineStyle',':','LineWidth',lwidth);
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−    set(h4(1), 'Color','b', 'LineStyle',':','LineWidth',lwidth);
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−    legend([h1(1),h2(1),h3(1)],{'Sample Probability','Reference','Conf. Bounds'},'Location','SouthEast')
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−    if ~isempty(axvect)
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−      axis(axvect);
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−    else
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−      axis([0 0.99 0 0.99])
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−    end
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−    h = [h1;h2;h3;h4];
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−    
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−  else % do empirical comparison
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−    % get empirical distribution for input data
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−    [eCD1,ex1]=utils.math.ecdf(y1);
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−    [eCD2,ex2]=utils.math.ecdf(y2);
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−    
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−    % get confidence levels with Kolmogorow - Smirnov test
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−    alp = (1-conf)/2;
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−    cVal = utils.math.SKcriticalvalues(numel(ex1),numel(ex2),alp);
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−    % get confidence levels
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−    CDu = eCD2+cVal;
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−    CDl = eCD2-cVal;
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−    
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−    % get probabilities corresponding for second distribution to first empirical
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−    % probabilities
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−    tp = interp1(ex2,eCD2,ex1);
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−
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−    % get upper and lower bounds for p
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−    pup = interp1(ex2,CDu,ex1);
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−    plw = interp1(ex2,CDl,ex1);
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−
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−    % empirical probabilities
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−    ep = eCD1;
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−
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−    figure
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−    h1 = plot(tp,ep);
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−    grid on
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−    hold on
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−    lnx = [min(tp) max(tp(1:end-1))];
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−    lny = [min(tp) max(tp(1:end-1))];
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−    h2 = line(lnx,lny,'Color','k');
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−    h3 = plot(tp,pup,'b--');
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−    h4 = plot(tp,plw,'b--');
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−    xlabel('Y2 Probability','FontSize',fontsize);
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−    ylabel('Y1 Probability','FontSize',fontsize);
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−    set(h1(1), 'Color','r', 'LineStyle','-','LineWidth',lwidth);
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−    set(h2(1), 'Color','k', 'LineStyle','--','LineWidth',lwidth);
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−    set(h3(1), 'Color','b', 'LineStyle',':','LineWidth',lwidth);
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−    set(h4(1), 'Color','b', 'LineStyle',':','LineWidth',lwidth);
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−    legend([h1(1),h2(1),h3(1)],{'Sample Probability','Reference','Conf. Bounds'},'Location','SouthEast')
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−    if ~isempty(axvect)
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−      axis(axvect);
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−    else
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−      axis([0 0.99 0 0.99])
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−    end
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−    h = [h1;h2;h3;h4];
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−  end
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−  
+
−end