% initialize  if strcmp(operation,'init') | ...     (strcmp(operation,'do') & strcmp(sNorm(i).status,'uninit')),     % case method = 'hist'    if strcmp(sNorm(i).method,'hist'),       inds = find(~isnan(x) & ~isinf(x));      if length(unique(x(inds)))>20, sNorm(i).method = 'histC';       else sNorm{i}.method = 'histD'; end    end    switch(sNorm(i).method),     case 'var',   params = norm_variance_init(x);    case 'range', params = norm_scale01_init(x);    case 'log',   params = norm_log_init(x);    case 'logistic', params = norm_logistic_init(x);    case 'histD', params = norm_histeqD_init(x);    case 'histC', params = norm_histeqC_init(x);    case 'eval',  params = sNorm(i).params;     otherwise,       error(['Unrecognized method: ' sNorm(i).method]);     end    sNorm(i).params = params;    sNorm(i).status = 'undone';  end  % do / undo  if strcmp(operation,'do'),     switch(sNorm(i).method),     case 'var',   x = norm_scale_do(x,sNorm(i).params);    case 'range', x = norm_scale_do(x,sNorm(i).params);    case 'log',   x = norm_log_do(x,sNorm(i).params);    case 'logistic', x = norm_logistic_do(x,sNorm(i).params);    case 'histD', x = norm_histeqD_do(x,sNorm(i).params);    case 'histC', x = norm_histeqC_do(x,sNorm(i).params);    case 'eval',  x = norm_eval_do(x,sNorm(i).params);    otherwise,       error(['Unrecognized method: ' sNorm(i).method]);    end    sNorm(i).status = 'done';  elseif strcmp(operation,'undo'),     if strcmp(sNorm(i).status,'uninit'),       warning('Could not undo: uninitialized normalization struct.')      break;    end    switch(sNorm(i).method),     case 'var',   x = norm_scale_undo(x,sNorm(i).params);    case 'range', x = norm_scale_undo(x,sNorm(i).params);    case 'log',   x = norm_log_undo(x,sNorm(i).params);        case 'logistic', x = norm_logistic_undo(x,sNorm(i).params);    case 'histD', x = norm_histeqD_undo(x,sNorm(i).params);    case 'histC', x = norm_histeqC_undo(x,sNorm(i).params);    case 'eval',  x = norm_eval_undo(x,sNorm(i).params);    otherwise,       error(['Unrecognized method: ' sNorm(i).method]);    end    sNorm(i).status = 'undone';  elseif ~strcmp(operation,'init'),    error(['Unrecognized operation: ' operation])  endend  return;%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% subfunctions% linear scalingfunction p = norm_variance_init(x)  inds = find(~isnan(x) & isfinite(x));  p = [mean(x(inds)), std(x(inds))];  if p(2) == 0, p(2) = 1; end  %end of norm_variance_initfunction p = norm_scale01_init(x)  inds = find(~isnan(x) & isfinite(x));  mi = min(x(inds));   ma = max(x(inds));  if mi == ma, p = [mi, 1]; else p = [mi, ma-mi]; end  %end of norm_scale01_init  function x = norm_scale_do(x,p)  x = (x - p(1)) / p(2);  % end of norm_scale_dofunction x = norm_scale_undo(x,p)  x = x * p(2) + p(1);  % end of norm_scale_undo% logarithmfunction p = norm_log_init(x)  inds = find(~isnan(x) & isfinite(x));  p = min(x(inds));  % end of norm_log_initfunction x = norm_log_do(x,p)  x = log(x - p +1);   % if any(~isreal(x)), ok = 0; end  % end of norm_log_do function x = norm_log_undo(x,p)  x = exp(x) -1 + p;   % end of norm_log_undo % logisticfunction p = norm_logistic_init(x)  inds = find(~isnan(x) & isfinite(x));  p = [mean(x(inds)), std(x(inds))];  if p(2)==0, p(2) = 1; end  % end of norm_logistic_initfunction x = norm_logistic_do(x,p)  x = (x-p(1))/p(2);  x = 1./(1+exp(-x));  % end of norm_logistic_dofunction x = norm_logistic_undo(x,p)  x = log(x./(1-x));  x = x*p(2)+p(1);  % end of norm_logistic_undo% histogram equalization for discrete valuesfunction p = norm_histeqD_init(x)  inds = find(~isnan(x) & ~isinf(x));  p = unique(x(inds));  % end of norm_histeqD_initfunction x = norm_histeqD_do(x,p)  bins = length(p);  inds = find(~isnan(x) & ~isinf(x))';  for i = inds,     [dummy ind] = min(abs(x(i) - p));    % data item closer to the left-hand bin wall is indexed after RH wall    if x(i) > p(ind) & ind < bins,       x(i) = ind + 1;      else       x(i) = ind;    end  end  x = (x-1)/(bins-1); % normalization between [0,1]  % end of norm_histeqD_do function x = norm_histeqD_undo(x,p)  bins = length(p);  x = round(x*(bins-1)+1);  inds = find(~isnan(x) & ~isinf(x));  x(inds) = p(x(inds));  % end of norm_histeqD_undo% histogram equalization with partially linear functionsfunction p = norm_histeqC_init(x)  % investigate x  inds = find(~isnan(x) & ~isinf(x));  samples = length(inds);  xs = unique(x(inds));  mi = xs(1);  ma = xs(end);  % decide number of limits  lims = ceil(sqrt(length(xs))); % 2->2,100->10,1000->32,10000->100  % decide limits  if lims==1,         p = [mi, mi+1];    lims = 2;   elseif lims==2,     p = [mi, ma];  else    p = zeros(lims,1);       p(1) = mi;     p(end) = ma;    binsize = zeros(lims-1,1); b = 1; avebinsize = samples/(lims-1);    for i=1:(length(xs)-1),       binsize(b) = binsize(b) + sum(x==xs(i));       if binsize(b) >= avebinsize,         b = b + 1;        p(b) = (xs(i)+xs(i+1))/2;      end      if b==(lims-1),         binsize(b) = samples-sum(binsize); break;      else        avebinsize = (samples-sum(binsize))/(lims-1-b);      end    end  end  % end of norm_histeqC_initfunction x = norm_histeqC_do(x,p)  xnew = x;   lims = length(p);  % handle values below minimum  r = p(2)-p(1);   inds = find(x<=p(1) & isfinite(x));   if any(inds), xnew(inds) = 0-(p(1)-x(inds))/r; end   % handle values above maximum  r = p(end)-p(end-1);   inds = find(x>p(end) & isfinite(x));   if any(inds), xnew(inds) = lims-1+(x(inds)-p(end))/r; end  % handle all other values  for i=1:(lims-1),     r0 = p(i); r1 = p(i+1); r = r1-r0;     inds = find(x>r0 & x<=r1);     if any(inds), xnew(inds) = i-1+(x(inds)-r0)/r; end  end  % scale so that minimum and maximum correspond to 0 and 1  x = xnew/(lims-1);  % end of norm_histeqC_dofunction x = norm_histeqC_undo(x,p)  xnew = x;   lims = length(p);   % scale so that 0 and 1 correspond to minimum and maximum  x = x*(lims-1);  % handle values below minimum  r = p(2)-p(1);   inds = find(x<=0 & isfinite(x));   if any(inds), xnew(inds) = x(inds)*r + p(1); end   % handle values above maximum  r = p(end)-p(end-1);   inds = find(x>lims-1 & isfinite(x));   if any(inds), xnew(inds) = (x(inds)-(lims-1))*r+p(end); end  % handle all other values  for i=1:(lims-1),     r0 = p(i); r1 = p(i+1); r = r1-r0;     inds = find(x>i-1 & x<=i);     if any(inds), xnew(inds) = (x(inds)-(i-1))*r + r0; end  end  x = xnew;  % end of norm_histeqC_undo% evalfunction p = norm_eval_init(method)  p = method;  %end of norm_eval_initfunction x = norm_eval_do(x,p)  x_tmp = eval(p{1});  if size(x_tmp,1)>=1 & size(x,1)>=1 & ...     size(x_tmp,2)==1 & size(x,2)==1,    x = x_tmp;  end  %end of norm_eval_dofunction x = norm_eval_undo(x,p)  x_tmp = eval(p{2});  if size(x_tmp,1)>=1 & size(x,1)>=1 & ...     size(x_tmp,2)==1 & size(x,2)==1,    x = x_tmp;  end  %end of norm_eval_undo%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%