%CONFMAT Construct confusion matrix % % [C,NE,LABLIST] = CONFMAT(LAB1,LAB2,METHOD,FID) % % INPUT % LAB1 Set of labels % LAB2 Set of labels % METHOD 'count' (default) to count number of co-occurences in % LAB1 and LAB2, 'disagreement' to count relative % non-co-occurrence. % FID Write text result to file % % OUTPUT % C Confusion matrix % NE Total number of errors (empty labels are neglected) % LABLIST Unique labels in LAB1 and LAB2 % % DESCRIPTION % Constructs a confusion matrix C between two sets of labels LAB1 % (corresponding to the rows in C) and LAB2 (the columns in C). The order of % the rows and columns is returned in LABLIST. NE is the total number of % errors (sum of non-diagonal elements in C). % % When METHOD = 'count' (default), co-occurences in LAB1 and LAB2 are counted % and returned in C. When METHOD = 'disagreement', the relative disagreement % is returned in NE, and is split over all combinations of labels in C % (such that the rows sum to 1). (The total disagreement for a class equals % one minus the sensitivity for that class as computed by TESTC). % % [C,NE,LABLIST] = CONFMAT(D,METHOD) % % If D is a classification result D = A*W, the labels LAB1 and LAB2 are % internally retrieved by CONFMAT before computing the confusion matrix. % % When no output argument is specified, or when FID is given, the % confusion matrix is displayed or written a to a text file. It is assumed % that LAB1 contains true labels and LAB2 stores estimated labels. % % EXAMPLE % Typical use of CONFMAT is the comparison of true and and estimated labels % of a testset A by application to a trained classifier W: % LAB1 = GETLABELS(A); LAB2 = A*W*LABELD. % More examples can be found in PREX_CONFMAT, PREX_MATCHLAB. % % SEE ALSO % MAPPINGS, DATASETS, GETLABELS, LABELD % Copyright: R.P.W. Duin, r.p.w.duin@prtools.org % Faculty EWI, Delft University of Technology % P.O. Box 5031, 2600 GA Delft, The Netherlands % $Id: confmat.m,v 1.7 2008/10/14 21:34:32 duin Exp $ function [CC,ne,lablist,lablist_true] = confmat_new (arg1,arg2,arg3,fid,lablist_true) prtrace(mfilename); % Check arguments. if nargin < 5, lablist_true = []; end if nargin < 4, fid = 1; end if nargin < 3 | isempty(arg3) if isdataset(arg1) lab1 = getlabels(arg1); lab2 = arg1*labeld; if nargin < 2| isempty(arg2) method = 'count'; prwarning(4,'no method supplied, assuming count'); else method = arg2; end else method = 'count'; prwarning(4,'no method supplied, assuming count'); lab1 = arg1; if (nargin < 2 | isempty(arg2)) error('prtools_addin','Second label list not supplied') end lab2 = arg2; end else lab1 = arg1; lab2 = arg2; method = arg3; end if nargin < 2 if ~isdataset(arg1) error('prtools_addin','two labellists or one dataset should be supplied') end end % Renumber LAB1 and LAB2 and find number of unique labels. m = size(lab1,1); if (m~=size(lab2,1)) error('prtools_addin','LAB1 and LAB2 have to have the same lengths.'); end if( isempty(lablist_true) ) [nlab1,nlab2,lablist] = renumlab(lab1,lab2); % n = max(nlab1); % n = max(nlab2); % n = max(n,n); n = size(lablist,1); else nlab1 = renumlab(lab1,lablist_true); nlab2 = renumlab(lab2,lablist_true); lablist = lablist_true; n = size(lablist,1); end % Construct matrix of co-occurences (confusion matrix). C = zeros(n+1,n+1); for i = 0:n K = find(nlab1==i); if (isempty(K)) C(i+1,:) = zeros(1,n+1); else for j = 0:n C(i+1,j+1) = length(find(nlab2(K)==j)); end end end % position rejects and unlabeled object at the end of the matrix D = C; D(1:end-1,1:end-1) = C(2:end,2:end); D(end,:) = [C(1,2:end) C(1,1)]; D(1:end-1,end) = C(2:end,1); C = D; D = D(1:end-1,1:end-1); DD = D(1:min(n,n),1:min(n,n)); % Calculate number of errors ('count') or disagreement ('disagreement'). % Neglect rejects if nargout > 1 J = find(nlab1~=0 & nlab2~=0); ne = nlabcmp(lab1(J,:),lab2(J,:)); end switch (method) case 'count' ne = sum(sum(D)) - sum(diag(DD)); % Diagonal entries are correctly % classified, so all off-diagonal % entries denote wrong ones. case 'disagreement' ne = (sum(sum(D)) - sum(diag(DD)))/m; % Relative sum of off-diagonal % entries. E = repmat(sum(D,2),1,n); % Disagreement = 1 - D = ones(n,n)-D./E; % relative co-occurence. D = D / (n-1); otherwise error('prtools_addin','unknown method'); end %Distinguish 'rejects / no_labels' from 'non_rejects / fully labeled' if (any(C(:,end) ~= 0) | any(C(end,:)~=0)) & strcmp(method,'count') n = n+1; n_real = n; labch = char(strlab(lablist),'reject'); labcv = char(strlab(lablist),'No'); else if( isempty(lablist_true) ) labcv = strlab(lablist); n_real = n; else labcv = lablist_true; n_real = size(lablist_true,1); end labch = strlab(lablist); %labcv = labch; C = D; end % If no output argument is specified, pretty-print C. if (nargout == 0) | nargin == 4 if nargin < 4, fid = 1; end % Make sure labels are stored in LABC as matrix of characters, % max. 6 per label. if (size(labch,2) > 6) labch = labch(:,1:6); %labcv = labcv(:,1:6); end if (size(labch,2) < 5) labch = [labch repmat(' ',n,ceil((5-size(labch,2))/2))]; % labcv = [labcv repmat(' ',n,ceil((5-size(labcv,2))/2))]; end %C = round(1000*C./repmat(sum(C,2),1,size(C,2))); nspace = max(size(labcv,2)-7,0); cspace = repmat(' ',1,nspace); %fprintf(fid,['\n' cspace ' | Estimated Labels']); fprintf(fid,['\n True ' cspace '| Estimated Labels']); fprintf(fid,['\n Labels ' cspace '|']); for j = 1:n, fprintf(fid,'%7s',labch(j,:)); end fprintf(fid,'|'); fprintf(fid,' Totals'); fprintf(fid,'\n '); fprintf(fid,repmat('-',1,8+nspace)); fprintf(fid,'|%s',repmat('-',1,7*n)); fprintf(fid,'|-------'); fprintf(fid,'\n '); for j = 1:min(n,n_real) fprintf(fid,' %-7s|',labcv(j,:)); switch (method) case 'count' fprintf(fid,'%5i ',C(j,:)'); fprintf(fid,'|'); fprintf(fid,'%5i',sum(C(j,:))); case 'disagreement' fprintf(fid,' %5.3f ',C(j,:)'); fprintf(fid,'|'); fprintf(fid,' %5.3f ',sum(C(j,:))); end fprintf(fid,'\n '); end fprintf(fid,repmat('-',1,8+nspace)); fprintf(fid,'|%s',repmat('-',1,7*n)); fprintf(fid,'|-------'); fprintf(fid,['\n Totals ' cspace '|']); switch (method) case 'count' fprintf(fid,'%5i ',sum(C)); fprintf(fid,'|'); fprintf(fid,'%5i',sum(C(:))); case 'disagreement' fprintf(fid,' %5.3f ',sum(C)); fprintf(fid,'|'); fprintf(fid,' %5.3f ',sum(C(:))); end fprintf(fid,'\n\n'); end if nargout > 0 CC = C; end return