%PLOTE Plot error curves
%
% H = PLOTE(E,LINEWIDTH,S,FONTSIZE,OPTIONS)
%
% INPUT
% E Structure containing error curves (see e.g. CLEVAL)
% LINEWIDTH Line width, < 5 (default 2)
% S Plot strings
% FONTSIZE Font size, >= 5 (default 16)
% OPTIONS Character strings:
% 'nolegend' suppresses the legend plot
% 'errorbar' add errorbars to the plot
% 'noapperror' suppresses the apparent error plot
%
% OUTPUT
% H Array of graphics handles
%
% DESCRIPTION
% Various evaluation routines like CLEVAL return an error curves packed in a
% structure E. PLOTE uses the information stored in E to plot the curves. The
% remaining parameters may be given in an arbitrary order.
%
% E may contain the following fields (E.ERROR is obligatory):
% E.ERROR C x N matrix of error values for C methods at N points
% (typically errors estimated on an independent test set)
% E.XVALUES C x N matrix of measurement points; if 1 x N, it is used for
% all C curves
% E.TITLE the title of the plot
% E.XLABEL the label for the x-axis
% E.YLABEL the label for the y-axis
% E.NAMES a string array of C names used for creating a LEGEND
% E.PLOT the plot command in a string: 'plot', 'semilogx', 'semilogy'
% or 'loglog'
% E.STD C x N matrix with standard deviations of the mean error values
% which are plotted if ERRBAR == 1
% Note that this is the st. dev. in the estimate of the mean
% and not the std. dev. of the error itself.
% E.APPERROR C x N matrix of error values for C methods at N points
% (typically errors estimated on the training set)
% E.APPSTD C x N matrix with standard deviations of the mean
% APPERROR values which are plotted if ERRBAR == 1
%
% These fields are automatically set by a series of commands like CLEVAL,
% CLEVALF, PRROC and REJECT.
%
% The legend generated by PLOTE can be removed by LEGEND OFF. A new legend
% may be created by the LEGEND command using the handles stored in H.
%
% E may be a cell array of structures. These structures are combined
% vertically, assuming multiple runs of the same method and
% horizontally, assuming different methods.
%
% EXAMPLES
% See PREX_CLEVAL
%
% SEE ALSO (<a href="http://37steps.com/prtools">PRTools Guide</a>)
% CLEVAL, CLEVALF, PRROC, REJECT
% Copyright: R.P.W. Duin, r.p.w.duin@37steps.com
% Faculty EWI, Delft University of Technology
% P.O. Box 5031, 2600 GA Delft, The Netherlands
% $Id: plote.m,v 1.5 2009/11/26 10:45:43 davidt Exp $
function handle = plote(varargin)
% Set default parameter values.
e = [];
s = [];
linewidth = 2;
nolegend = 0;
fontsize = 16;
errbar = 1;
noapperror = 0;
ss = char('k-','r-','b-','m-','k--','r--','b--','m--');
ss = char(ss,'k-.','r-.','b-.','m-.','k:','r:','b:','m:');
ss_app = char('k--','r--','b--','m--','k:','r:','b:','m:');
ss_app = char(ss_app,'k--','r--','b--','m--','k-','r-','b-','m-');
% The input is so flexible, that we have to do a lot of work...
for j = 1:nargin
p = varargin{j};
if (isstruct(p)) | iscell(p)
e = p;
elseif (isstr(p)) & (strcmp(p,'errorbar') | strcmp(p,'ERRORBAR'))
errbar = 1;
elseif (isstr(p)) & (strcmp(p,'nolegend') | strcmp(p,'NOLEGEND'))
nolegend = 1;
elseif (isstr(p)) & (strcmp(p,'noapperror') | strcmp(p,'NOAPPERROR'))
noapperror = 1;
elseif (isstr(p))
ss = p;
elseif (length(p) == 1) & (p < 5)
linewidth = p;
elseif (length(p) == 1) & (p >= 5)
fontsize = p;
end
end
if iscell(e)
if min(size(e)) > 1
ee = cell(1,size(e,2));
for j=1:size(e,2)
ee{j} = vertcomb(e(:,j));
end
e = horzcomb(ee);
elseif size(e,1) > 1
for j=1:size(e,1)
if j>1, figure; end
plote(e{j});
end
showfigs
return
%e = vertcomb(e);
elseif size(e,2) > 1
e = horzcomb(e);
else
e = e{1};
end
end
% Handle multiple plots
if length(e) > 1
names = [];
hold_stat = ishold;
h = [];
ymax = 0;
xmax = 0;
for j = 1:length(e)
if errbar & isfield(e,'std')
if noapperror
hh = plote(e(j),linewidth,ss(j,:),'nolegend','errorbar','noapperror');
else
hh = plote(e(j),linewidth,ss(j,:),'nolegend','errorbar');
end
else
if noapperror
hh = plote(e(j),linewidth,ss(j,:),'nolegend','noapperror');
else
hh = plote(e(j),linewidth,ss(j,:),'nolegend');
end
end
V = axis;
ymax = max(ymax,V(4));
xmax = max(xmax,V(2));
hold on
if ~isfield(e(j),'names')
e(j).names = ' ';
end
names = correct_(char(names,e(j).names));
h = [h(:); hh(:)];
end
names(1,:) = [];
V(4) = ymax;
V(2) = xmax;
axis(V);
if ~nolegend
legend(h,correct_(names),0);
end
if ~hold_stat, hold off; end
if nargout > 0, handle = h; end
return
end
% Check if we have the required data and data fields.
if (isempty(e))
error('Error structure not specified.')
end
if (~isfield(e,'error'))
error('Input structure should contain the ''error''-field.');
end
n = size(e.error,1);
if (~isfield(e,'xvalues'))
e.xvalues = [1:length(e.error)];
end
if (size(e.xvalues,1) == 1)
e.xvalues = repmat(e.xvalues,n,1);
end
if (isempty(s))
if n > size(ss,1)
nn = ceil(n/size(ss,1));
ss = repmat(ss,nn,1);
ss_app = repmat(ss_app,nn,1);
end
s = ss(1:n,:);
s_app = ss_app(1:n,:);
end
if (size(s,1) == 1) & (n > 1)
s = repmat(s,n,1);
s_app = repmat(s_app,n,1);
end
if (size(s,1) < n)
error('Insufficient number of plot strings.')
end
if (~isfield(e,'plot'))
e.plot = 'plot';
end
if errbar & isfield(e,'std')
ploterrorbar = 1;
else
ploterrorbar = 0;
end
plotapperror = (~noapperror && isfield(e,'apperror'));
% We can now start making the plot.
if ~ishold
clf;
end
h = []; ha = []; % handles for true and apparent error
for j = 1:n
L = find(e.error(j,:) ~= NaN);
if ploterrorbar
hh = feval('errorbar',e.xvalues(j,L),e.error(j,L),e.std(j,L),deblank(s(j,:)));
else
hh = feval(e.plot,e.xvalues(j,L),e.error(j,L),deblank(s(j,:)));
end
set(hh,'linewidth',linewidth); hold on; h = [h hh(end)];
% and the apparent error
if plotapperror
hh = errorbar(e.xvalues(j,L),e.apperror(j,L),e.appstd(j,L),...
deblank(s_app(j,:)));
ha = [ha hh(end)];
end
end
% That was basically it, now we only have to beautify it.
errmax = max(e.error(:));
set(gca,'fontsize',fontsize);
if (isfield(e,'xlabel')), xlabel(correct_(e.xlabel)); end
if (isfield(e,'ylabel')), ylabel(correct_(e.ylabel)); end
if (isfield(e,'title')), title(correct_(e.title)); end
if (isfield(e,'names')) & (~isempty(e.names) & (~nolegend))
if plotapperror % take care for the legend in this case
nrn = size(e.names,1);
e.names = correct_(e.names);
names = {};
for j=1:nrn
names{j} = ['\epsilon ' e.names(j,:)];
%names{j} = ['true error ' e.names(j,:)];
end
for j=1:nrn
names{nrn+j} = ['\epsilon_A ' e.names(j,:)];
%names{nrn+j} = ['apparent error ' e.names(j,:)];
end
legend([h ha],strvcat(names),0);
else
legend(h,correct_(e.names),0);
end
end
% A lot of work to make the scaling of the y-axis nice.
if (errmax > 0.6)
errmax = ceil(errmax*5)/5;
yticks = [0:0.2:errmax];
elseif (errmax > 0.3)
errmax = ceil(errmax*10)/10;
yticks = [0:0.1:errmax];
elseif (errmax > 0.2)
errmax = ceil(errmax*20)/20;
yticks = [0:0.05:errmax];
elseif (errmax > 0.1)
errmax = ceil(errmax*30)/30;
yticks = [0:0.03:errmax];
elseif (errmax > 0.06)
errmax = ceil(errmax*50)/50;
yticks = [0:0.02:errmax];
elseif (errmax > 0.03)
errmax = ceil(errmax*100)/100;
yticks = [0:0.01:errmax];
else
yticks = [0:errmax/3:errmax];
end
% atttempt to beautify plot
if (e.xvalues(end) >= 2)
%DXD
%axis([e.xvalues(1)-1,e.xvalues(end)+1,0,errmax]);
axis([min(min(e.xvalues)),max(max(e.xvalues)),0,errmax]);
elseif (e.xvalues(1) == 0)
axis([-0.003,e.xvalues(end),0,errmax]);
end
set(gca,'ytick',yticks);
hold off; if (nargout > 0), handle = h; end;
return
function e = vertcomb(e) % combine cell array
e1 = e{1};
for j=2:length(e);
e2 = e{j};
v = e1.n*(e1.n*(e1.std.^2) + e1.error.^2);
v = v + e2.n*(e2.n*(e2.std.^2) + e2.error.^2);
n = e1.n + e2.n;
e1.error = (e1.n*e1.error + e2.n*e2.error)/n;
e1.std = sqrt((v/n - e1.error.^2)/n);
e1.n = n;
end
e = e1;
return
function ee = horzcomb(e) % combine cell array
isx = false;
isy = false;
isd = false;
for j=1:length(e)
isx = (isx || strcmp(e{j}.plot,'semilogx'));
isy = (isy || strcmp(e{j}.plot,'semilogy'));
isd = (isd || strcmp(e{j}.plot,'loglog'));
end
if isx && isy, isd = true; end
for j=1:length(e)
if isd
e{j}.plot = 'loglog';
elseif isx
e{j}.plot = 'semilogx';
elseif isy
e{j}.plot = 'semilogy';
else
e{j}.plot = 'plot';
end
ee(j) = e{j};
end
function s = correct_(s) %correct string for underscores
if size(s,1) > 1
ss = cell(1,size(s,1));
for j=1:size(s,1)
ss{j} = correct_(s(j,:));
end
s = char(ss);
return
end
J = find(s=='_');
if ~isempty(J)
J = fliplr(J(:)');
for j=1:length(J)
if s(J(j)-1) ~= '\'
s = [s(1:J(j)-1) '\' s(J(j):end)];
end
end
end
return