matthiasm@8: %
matthiasm@8: % PARSEDEGREE
matthiasm@8: % 
matthiasm@8: % [interval, accidentals, success, errormessage] = parsedegree(degree, {verbose})
matthiasm@8: % 
matthiasm@8: % Parse a degree to an interval value and a number of accidentals
matthiasm@8: % if accidentals is positive it denotes number of sharps,
matthiasm@8: % if it is negative it denotes number of flats.
matthiasm@8: % If the omit degree character '*' is found then present is returned as 0 
matthiasm@8: % otherwise it is 1. 
matthiasm@8: %
matthiasm@8: % Success = 1 if symbols parsed correctly, 0 otherwise.
matthiasm@8: %
matthiasm@8: % If optional argument 'verbose' is 1, function prints any errormessage to 
matthiasm@8: % the screen.
matthiasm@8: % 
matthiasm@8: % returns:  interval    (integer)
matthiasm@8: %           accidentals (integer) 
matthiasm@8: %           present     (boolean)
matthiasm@8: %           success     (boolean)
matthiasm@8: %           errormessage (string)  
matthiasm@8: %
matthiasm@8: % Author: Christopher Harte,  August 2005
matthiasm@8: % 
matthiasm@8: % Copyright: Centre for Digital Music, Queen Mary University of London 2005 
matthiasm@8: %
matthiasm@8: % This file is part of the C4DM Chord Toolkit.  
matthiasm@8: %
matthiasm@8: % The C4DM Chord Toolkit is free software; you can redistribute it and/or 
matthiasm@8: % modify it under the terms of the GNU General Public License as published 
matthiasm@8: % by the Free Software Foundation; either version 2 of the License, or
matthiasm@8: % (at your option) any later version.
matthiasm@8: %
matthiasm@8: % The C4DM Chord Toolkit is distributed in the hope that it will be useful,
matthiasm@8: % but WITHOUT ANY WARRANTY; without even the implied warranty of
matthiasm@8: % MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
matthiasm@8: % GNU General Public License for more details.
matthiasm@8: %
matthiasm@8: % You should have received a copy of the GNU General Public License
matthiasm@8: % along with the C4DM Toolkit; if not, write to the Free Software
matthiasm@8: % Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
matthiasm@8: 
matthiasm@8: %
matthiasm@8: function [interval,accidentals,present,success, errormessage] = parsedegree(degree, verbose)
matthiasm@8: 
matthiasm@8: if nargin < 2
matthiasm@8:     verbose = 0;
matthiasm@8: end
matthiasm@8: 
matthiasm@8: ilength = length(degree);
matthiasm@8: 
matthiasm@8: errormessage = '';
matthiasm@8: accidentals = 0;
matthiasm@8: interval = 0;
matthiasm@8: success=1;
matthiasm@8: present = 1;
matthiasm@8: 
matthiasm@8: index = 1;
matthiasm@8:  
matthiasm@8: % if the input string is not empty   
matthiasm@8: if (isempty(degree) == 0)
matthiasm@8: 
matthiasm@8:     
matthiasm@8:     % check for omit degree '*'
matthiasm@8:     if degree(index) == '*' 
matthiasm@8:         present = 0;
matthiasm@8:         index = index +1;
matthiasm@8:     end
matthiasm@8: 
matthiasm@8: 
matthiasm@8:     tempstring = '';
matthiasm@8:     tempindex = 1;
matthiasm@8:     % parse the degree string
matthiasm@8:     while index <= ilength
matthiasm@8: 
matthiasm@8:         switch degree(index)
matthiasm@8: 
matthiasm@8:             case 'b' % FLAT
matthiasm@8:                 accidentals = accidentals - 1; %decrement accidental count
matthiasm@8:                 index = index + 1;
matthiasm@8: 
matthiasm@8:             case '#' % SHARP
matthiasm@8:                 accidentals = accidentals + 1; %increment accidental count
matthiasm@8:                 index = index + 1;
matthiasm@8:              
matthiasm@8:             case {'1','2','3','4','5','6','7','8','9'}
matthiasm@8:                 % if neither of the above then remaining string should be
matthiasm@8:                 % an integer interval value
matthiasm@8:                 tempstring(tempindex) = degree(index);
matthiasm@8:                 
matthiasm@8:                 tempindex = tempindex+1;
matthiasm@8:                 index = index+1;
matthiasm@8:                 
matthiasm@8:             otherwise
matthiasm@8:                 % unrecognised symbol
matthiasm@8:                 success=0;
matthiasm@8:                 index = ilength+1;
matthiasm@8:         end
matthiasm@8:     end
matthiasm@8: else
matthiasm@8:     success=0;
matthiasm@8: end
matthiasm@8: 
matthiasm@8: if success
matthiasm@8: 
matthiasm@8: % convert the interval string to an integer
matthiasm@8:     [interval, success] = str2num(tempstring); 
matthiasm@8: 
matthiasm@8:     % check it worked and that the interval is valid
matthiasm@8:     if isempty(interval) || (interval <= 0) 
matthiasm@8:         success = 0; 
matthiasm@8:     end
matthiasm@8: end            
matthiasm@8: 
matthiasm@8: if(success==0) % correct degree therefore return success = 1 
matthiasm@8:     % if not an integer then the degree string is incorrect
matthiasm@8:     errormessage = sprintf(['Error in parsedegree: Unrecognised degree "' degree '"\n']);
matthiasm@8:     interval = 0;
matthiasm@8:     if verbose == 1
matthiasm@8:         fprintf(1, errormessage);
matthiasm@8:     end
matthiasm@8:     
matthiasm@8: end