christopherh@1: %
christopherh@1: % DEGREE2SEMITONE
christopherh@1: % 
christopherh@1: % [semitone, success, errormessage] = degree2semitone(degree, accidental, {verbose})
christopherh@1: % 
christopherh@1: % Convert a degree and accidentals pair to a semitone value
christopherh@1: % 
christopherh@1: % Success = 1 if degree converted correctly, 0 otherwise.
christopherh@1: % 
christopherh@1: % If optional argument 'verbose' is 1, function prints any errormessage to 
christopherh@1: % the screen.
christopherh@1: % 
christopherh@1: % returns:  semitone (string)
christopherh@1: %           success (boolean)
christopherh@1: %           errormessage (string)
christopherh@1: %
christopherh@1: % Author: Christopher Harte,  March 2009
christopherh@1: % 
christopherh@1: % Copyright: Centre for Digital Music, Queen Mary University of London 2005 
christopherh@1: %
christopherh@1: % This file is part of the C4DM Chord Toolkit V2.0  
christopherh@1: %
christopherh@1: % The C4DM Chord Toolkit is free software; you can redistribute it and/or 
christopherh@1: % modify it under the terms of the GNU General Public License as published 
christopherh@1: % by the Free Software Foundation; either version 2 of the License, or
christopherh@1: % (at your option) any later version.
christopherh@1: %
christopherh@1: % The C4DM Chord Toolkit is distributed in the hope that it will be useful,
christopherh@1: % but WITHOUT ANY WARRANTY; without even the implied warranty of
christopherh@1: % MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
christopherh@1: % GNU General Public License for more details.
christopherh@1: %
christopherh@1: % You should have received a copy of the GNU General Public License
christopherh@1: % along with the C4DM Toolkit; if not, write to the Free Software
christopherh@1: % Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
christopherh@1: 
christopherh@1: %		
christopherh@1: function [semitone, success, errormessage] = degree2semitone(degree, accidentals, verbose)
christopherh@1: 
christopherh@1: if nargin < 3 
christopherh@1:     % verbose defaults 0
christopherh@1:     verbose = 0;
christopherh@1: end
christopherh@1: 
christopherh@1: errormessage = '';
christopherh@1: 
christopherh@1: % semitone equivalents for degrees
christopherh@1: %             degree   1,2,3,4,5,6,7         
christopherh@1: %semitonetranslation = [0,2,4,5,7,9,11];
christopherh@1: 
christopherh@1: semitone = 0;
christopherh@1: 
christopherh@1: success = 1;
christopherh@1: 
christopherh@1: if (degree > 0) && (degree < 50)
christopherh@1: 
christopherh@1: % semitone value is the number of semitones equivalent to the degree
christopherh@1: % added to the number of accidentals (sharps are positive, flats are
christopherh@1: % negative) and the number of octaves above the reference note to
christopherh@1: % account for extensions 
christopherh@1: 
christopherh@1: %semitone = semitonetranslation(mod(degree,8) + fix(degree/8)) + accidentals + 12*fix(degree/8);
christopherh@1: 
christopherh@1: semitone = 2*mod(degree-1,7) - floor((mod(degree-1,7)+1)/4) + 12*floor((degree-1)/7)+ accidentals; 
christopherh@1: 
christopherh@1: else
christopherh@1:     success = 0;
christopherh@1:     
christopherh@1:     errormessage = sprintf('Error in degree2semitone: out of range degree "%d"\n', degree);
christopherh@1:     
christopherh@1:     if verbose == 1
christopherh@1:         fprintf(1,errormessage);
christopherh@1:     end
christopherh@1: end
christopherh@1: