diff chordtools/note2pitchclass.m @ 1:8973548174c1 tip

adding tools to repo

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/chordtools/note2pitchclass.m	Mon May 06 14:43:47 2013 +0100
@@ -0,0 +1,126 @@
+%
+%NOTE2PITCHCLASS convert a note to a pitchclass value w.r.t middle C
+% 
+% [pitchclass, success, errormessage] = note2pitchclass(note, {verbose})
+% 
+% Converts a note string to a pitch class (integer) with C as reference 
+% pitch class 0
+% 
+% Success = 1 if symbols parsed correctly, 0 otherwise.
+%
+% If optional argument 'verbose' is 1, function prints any errormessage to 
+% the screen.
+% 
+% returns:  pitchclass (integer)
+%           success (boolean)
+%           errormessage (string)
+%
+%
+% Author: Christopher Harte, March 2009
+% 
+% Copyright: Centre for Digital Music, Queen Mary University of London 2005 
+%
+% This file is part of the C4DM Chord Toolkit V2.0  
+%
+% The C4DM Chord Toolkit is free software; you can redistribute it and/or 
+% modify it under the terms of the GNU General Public License as published 
+% by the Free Software Foundation; either version 2 of the License, or
+% (at your option) any later version.
+%
+% The C4DM Chord Toolkit is distributed in the hope that it will be useful,
+% but WITHOUT ANY WARRANTY; without even the implied warranty of
+% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+% GNU General Public License for more details.
+%
+% You should have received a copy of the GNU General Public License
+% along with the C4DM Toolkit; if not, write to the Free Software
+% Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+%
+function [pitchclass, success, errormessage] = note2pitchclass(note, verbose)
+
+if nargin < 2
+    verbose = 0;
+end
+
+errormessage = '';
+
+ilength = length(note);
+
+index = 1;
+success = 1;
+
+
+% first char should be a natural name A-G
+switch note(index)
+
+    case 'C' % natural C
+            pitchclass = 0; 
+            index = index + 1;
+
+    case 'D' % natural D
+            pitchclass = 2; 
+            index = index + 1;
+    
+    case 'E' % natural E
+            pitchclass = 4; 
+            index = index + 1;
+    
+    case 'F' % natural F
+            pitchclass = 5; 
+            index = index + 1;
+    
+    case 'G' % natural G
+            pitchclass = 7; 
+            index = index + 1;
+    
+    case 'A' % natural A
+            pitchclass = 9; 
+            index = index + 1;
+    
+    case 'B' % natural B
+            pitchclass = 11; 
+            index = index + 1;
+            
+    otherwise %Unrecognised character
+            errormessage = sprintf(['Error in Note2PitchClass: Unrecognised note "' note '"\n']);
+            index = ilength + 1;
+            pitchclass=-1;
+            success = 0;
+         
+end
+
+% any other characters should be either flats or sharps
+while index <= ilength
+           
+    switch(note(index))
+        
+        case 'b' % FLAT
+            pitchclass = pitchclass - 1; %decrement pitchclass value
+            index = index + 1;
+            
+        case '#' % SHARP
+            pitchclass = pitchclass + 1; %increment pitchclass value
+            index = index + 1;
+        
+        otherwise % Unrecognised character
+            errormessage = sprintf(['Error in Note2PitchClass: Unrecognised note "' note '"\n']);
+            index = ilength + 1;
+            pitchclass=-1;
+            success = 0;
+    end        
+            
+end
+
+% Use modulo command to make sure that we are back within range 0-12
+if(success == 1)
+    
+    pitchclass = mod(pitchclass,12);
+    
+else
+   if(verbose == 1)
+      fprintf(1,errormessage); 
+   end
+end
+
+            
\ No newline at end of file