plotroc.m

数据挖掘的工具箱,最新版的,希望对做这方面研究的人有用

function h = plotroc(e,varargin)
%PLOTROC Draw an ROC curve
%
%     H = PLOTROC(E)
%
% Plot the roc curve of E according to the 'traditional' way: on the x
% axis we put the false positive (outliers accepted) and on the y axis
% we put the true positive (targets accepted).
%
%     H = PLOTROC(E,LINESTYLE)
%
% When required, a second argument can be given, indicating the color,
% LINESTYLE and markers of the plot. See 'plot' for the possibilities.
%
% See also dd_error, dd_roc, dd_auc

% Copyright: D.M.J. Tax, R.P.W. Duin, [e-mail]
% Faculty of Applied Physics, Delft University of Technology
% P.O. Box 5046, 2600 GA Delft, The Netherlands

% default settings:
mrk = 'b-';
fs = 16;
lw = 2;
oldplot=0;

% Be a bit flexible, and try to detect when one wants to use the
% old/nonstandard ROC curve:
if ~isempty(varargin)
	if length(varargin)>1 %Both color and oldplot are given
		if ~isempty(varargin{1})
			oldplot = 1;
		end
		mrk = varargin{end};
	else                  %Only color or oldplot is given
		if ischar(varargin{1})
			mrk = varargin{1};
		else
			oldplot = 1;
		end
	end
end

% transpose e if required:
if size(e,1)==2
	e = e';
end

% and here we plot:
if oldplot>0
	h = plot(e(:,1), e(:,2),mrk);
	xlabel('targets rejected (FN)','fontsize',fs);
	ylabel('outliers accepted (FP)','fontsize',fs);
else
	h = plot(e(:,2), 1-e(:,1),mrk);
	xlabel('outliers accepted (FP)','fontsize',fs);
	ylabel('targets accepted (TP)','fontsize',fs);
end
set(h,'linewidth',lw);

% Want this in most cases:
axis([0 1 0 1]);
hold on;

% If no handles are requested, remove them:
if nargout==0
  clear h;
end

return