%% This reads a problem (in svmlight format) and% return label vector and features in sparse matrix.%function [svm_lbl, svm_data] = read_sparse(fname); fid = fopen(fname); line = 0; elements = 0;svm_lbl = []; svm_data = []; while 1 	tline = fgetl(fid); 	if ~ischar(tline), break, end 	line = line + 1; 	[lbl, data] = strtok(tline); 	svm_lbl(line, 1) = sscanf(lbl, '%g'); 	[c, v] = strread(data, '%d:%f'); 	elements = elements + length(c);endfrewind(fid);row = zeros(elements,1);col = zeros(elements,1);value = zeros(elements,1);elements = 1;for i = 1:line	tline = fgetl(fid); 	if ~ischar(tline), break, end 	[lbl, data] = strtok(tline); 	svm_lbl(i, 1) = sscanf(lbl, '%g'); 	[c, v] = strread(data, '%d:%f'); 	s = elements;	e = elements + length(c) - 1;		row(s:e, 1) = i * ones(length(c), 1);	col(s:e, 1) = c;	value(s:e, 1) = v;	elements = elements + length(c);endsvm_data = sparse(row, col, value); fclose(fid);