File: node1.html

package info (click to toggle)
mma 16.06-2
  • links: PTS, VCS
  • area: main
  • in suites: buster
  • size: 45,212 kB
  • sloc: python: 14,894; sh: 26; makefile: 13; perl: 12
file content (812 lines) | stat: -rw-r--r-- 24,649 bytes parent folder | download | duplicates (2)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">

<!--Converted with LaTeX2HTML 2008 (1.71)
original version by:  Nikos Drakos, CBLU, University of Leeds
* revised and updated by:  Marcus Hennecke, Ross Moore, Herb Swan
* with significant contributions from:
  Jens Lippmann, Marek Rouchal, Martin Wilck and others -->
<HTML>
<HEAD>
<TITLE>Overview and Introduction</TITLE>
<META NAME="description" CONTENT="Overview and Introduction">
<META NAME="keywords" CONTENT="mma">
<META NAME="resource-type" CONTENT="document">
<META NAME="distribution" CONTENT="global">

<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=utf-8">
<META NAME="Generator" CONTENT="LaTeX2HTML v2008">
<META HTTP-EQUIV="Content-Style-Type" CONTENT="text/css">

<LINK REL="STYLESHEET" HREF="mma.css">

<LINK REL="next" HREF="node2.html">
<LINK REL="previous" HREF="mma.html">
<LINK REL="up" HREF="mma.html">
<LINK REL="next" HREF="node2.html">
</HEAD>

<BODY  bgcolor="#ffffff">

<DIV CLASS="navigation"><!--Navigation Panel-->
<A NAME="tex2html458"
  HREF="node2.html">
<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next.png"></A> 
<A NAME="tex2html456"
  HREF="mma.html">
<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up.png"></A> 
<A NAME="tex2html450"
  HREF="mma.html">
<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="prev.png"></A>   
<BR>
<B> Next:</B> <A NAME="tex2html459"
  HREF="node2.html">Running</A>
<B> Up:</B> <A NAME="tex2html457"
  HREF="mma.html">Reference Manual</A>
<B> Previous:</B> <A NAME="tex2html451"
  HREF="mma.html">Reference Manual</A>
<BR>
<BR></DIV>
<!--End of Navigation Panel-->
<!--Table of Child-Links-->
<A NAME="CHILD_LINKS"><STRONG>Subsections</STRONG></A>

<UL CLASS="ChildLinks">
<LI><A NAME="tex2html460"
  HREF="node1.html#SECTION00110000000000000000">License, Version and Legalities</A>
<LI><A NAME="tex2html461"
  HREF="node1.html#SECTION00120000000000000000">About this Manual</A>
<UL>
<LI><A NAME="tex2html462"
  HREF="node1.html#SECTION00121000000000000000">Typographic Conventions</A>
<LI><A NAME="tex2html463"
  HREF="node1.html#SECTION00122000000000000000"><SPAN CLASS="logo,LaTeX">L<SUP><SMALL>A</SMALL></SUP>T<SMALL>E</SMALL>X</SPAN> and HTML</A>
<LI><A NAME="tex2html464"
  HREF="node1.html#SECTION00123000000000000000">Other Documentation</A>
<LI><A NAME="tex2html465"
  HREF="node1.html#SECTION00124000000000000000">Music Notation</A>
</UL>
<BR>
<LI><A NAME="tex2html466"
  HREF="node1.html#SECTION00130000000000000000">Installing 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT> </A>
<LI><A NAME="tex2html467"
  HREF="node1.html#SECTION00140000000000000000">Running 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT> </A>
<LI><A NAME="tex2html468"
  HREF="node1.html#SECTION00150000000000000000">Comments</A>
<LI><A NAME="tex2html469"
  HREF="node1.html#SECTION00160000000000000000">Theory Of Operation</A>
<LI><A NAME="tex2html470"
  HREF="node1.html#SECTION00170000000000000000">Case Sensitivity</A>
</UL>
<!--End of Table of Child-Links-->
<HR>

<H1><A NAME="SECTION00100000000000000000">
Overview and Introduction</A>
</H1>

<P>
<SPAN  CLASS="textit">Musical MIDI Accompaniment</SPAN>, 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT> ,<A NAME="tex2html1"
  HREF="#foot223"><SUP><SPAN CLASS="arabic">1</SPAN>.<SPAN CLASS="arabic">1</SPAN></SUP></A> generates standard
MIDI<A NAME="tex2html2"
  HREF="#foot213"><SUP><SPAN CLASS="arabic">1</SPAN>.<SPAN CLASS="arabic">2</SPAN></SUP></A> files which can be used as a backup track for a soloist.
It was written especially for me--I am an aspiring saxophonist and
wanted a program to ``play'' the piano and drums so I could practice
my jazz solos. With 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  I can create a track based on the chords in
a song, transpose it to the correct key for my instrument, and play my
very bad improvisations until they get a bit better.

<P>
I also lead a small combo group which is always missing at least one
player. With 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  generated tracks the group can practice and
perform even if a rhythm player is missing. This all works much better
than I expected when I started to write the program ... so much
better that I have used 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  generated tracks for live performances
with great success.

<P>
Around the world musicians are using 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  for practice, performance
and in their studios. Much more than ever imagined when this project
was started!

<P>

<H1><A NAME="SECTION00110000000000000000">
License, Version and Legalities</A>
</H1>

<P>
The program 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  was written by and is copyright Robert van der
Poel, 2003--2015.

<P>
This program, the accompanying documentation, and library files can be
freely distributed according to the terms of the GNU General Public
License (see the distributed file ``COPYING'').

<P>
If you enjoy the program, make enhancements, find bugs, etc. send a
note to me at 
    
      <A HREF="mailto:bob@mellowood.ca"> Bob van der Poel </A>; or a postcard (or even money) to PO Box 57,
Wynndel, BC, Canada V0B 2N0.

<P>
The current version of this package is maintained at: <TT><A NAME="tex2html3"
  HREF="http://www.mellowood.ca/mma/">http://www.mellowood.ca/mma/</A></TT>.

<P>
This document reflects version 16.06
 of 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT> .

		<Table CellSpacing=0 Width="80%" Align="Center" CellPadding=10 BGColor="#dddddd" Border=3>
           <tr> <td>
	       <BR><SPAN  CLASS="textit"> I have done everything I can
    to ensure that the program functions as advertised, but I assume
    no responsibility for <SPAN  CLASS="textbf">anything</SPAN> it does to your computer
    or data.</SPAN>

<P>
<BR>
  <DIV ALIGN="CENTER">
Sorry for this disclaimer, but we live in paranoid times.
  
</DIV>
  <BR>

<P>
This manual most likely has lots of errors. Spelling, grammar, and
  probably a number of the examples need fixing. Please give me a hand
  and report anything ... it'll make it much easier for me to
  generate a really good product for all of us to enjoy.

<P>
<BR> 
	
           </td></tr>
        </Table>

<P>

<H1><A NAME="SECTION00120000000000000000">
About this Manual</A>
</H1>

<P>
This manual was written by the program author--and this is always a
very bad idea. But, having no volunteers, the choice is no manual at
all or my bad perspectives.<A NAME="tex2html4"
  HREF="#foot259"><SUP><SPAN CLASS="arabic">1</SPAN>.<SPAN CLASS="arabic">3</SPAN></SUP></A>
<P>

<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  is a large and complex program. It really does need a manual;
and users really need to refer to the manual to get the most out of
the program. Even the author frequently refers to the manual. Really.

<P>
I have tried to present the various commands in a logical and useful
order. The table of contents should point you quickly to the relevant
sections.

<P>

<H2><A NAME="SECTION00121000000000000000">
Typographic Conventions</A>
</H2>

<P>

<UL>
<LI>The name of the program is always set in the special logo type:
  
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT> .

<P>
</LI>
<LI>
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  commands and directives are set in small caps:
  D<SMALL>IRECTIVE</SMALL>.

<P>
</LI>
<LI>Important stuff is emphasized: <SPAN  CLASS="textit">important</SPAN>.

<P>
</LI>
<LI>Websites look like this:
  <TT><A NAME="tex2html5"
  HREF="http://www.mellowood.ca/mma/index.html">http://www.mellowood.ca/mma/index.html</A></TT>
<P>
</LI>
<LI>Filenames are set in bold typewriter font: <TT><SPAN  CLASS="textbf">filename.mma</SPAN></TT>

<P>
</LI>
<LI>Lines extracted from a 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  input file are set on individual
  lines:

<P>

      <Table Hspace="40%" CellSpacing=0 CellPadding=10 BGColor="OldLace" Border=3>
        <tr><td>
    <B>A command from a file  </B> 
   
	    </td></tr>
      </Table>

<P>
</LI>
<LI>Commands you should type from a shell prompt (or other operating
  system interface) have a leading <TT>$</TT> (to indicate a shell
  prompt) and are shown on separate lines:

<P>

      <Table Hspace="40%" CellSpacing=0 CellPadding=10 BGColor="OldLace" Border=3>
        <tr><td>
    <B>$ enter this  </B> 
   
	    </td></tr>
      </Table>

<P>
</LI>
</UL>

<P>

<H2><A NAME="SECTION00122000000000000000">
<SPAN CLASS="logo,LaTeX">L<SUP><SMALL>A</SMALL></SUP>T<SMALL>E</SMALL>X</SPAN> and HTML</A>
</H2>

<P>
The manual has been prepared with the <SPAN CLASS="logo,LaTeX">L<SUP><SMALL>A</SMALL></SUP>T<SMALL>E</SMALL>X</SPAN> typesetting system.
Currently, there are two versions available: the primary version is a
PDF file intended for printing or on-screen display (generated with
<TT>dvipdf</TT>); the secondary version is in HTML (transformed with
<SPAN CLASS="logo,LaTeX2HTML">L<SUP><SMALL>A</SMALL></SUP>T<SMALL>E</SMALL>X2<TT>HTML</TT></SPAN>) for electronic viewing. If other formats are needed
... please offer to volunteer.

<P>

<H2><A NAME="SECTION00123000000000000000">
Other Documentation</A>
</H2>

<P>
In addition to this document the following other items are recommended
reading:

<P>

<UL>
<LI>The standard library documentation supplied with this document
  in PDF and HTML formats.

<P>
</LI>
<LI>The 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  tutorial supplied with this document in PDF and HTML
  formats.

<P>
</LI>
<LI>A short reference on writing P<SMALL>LUGIN</SMALL>s is available in both
  PDF and HTML formats.

<P>
</LI>
<LI>Various <TT><SPAN  CLASS="textbf">README</SPAN></TT> files in the distribution.

<P>
</LI>
<LI>The Python source files.

<P>
</LI>
</UL>

<P>

<H2><A NAME="SECTION00124000000000000000">
Music Notation</A>
</H2>

<P>
The various snippets of standard music notation in this manual have
been prepared with the MUP program. I highly recommend this program
and use it for most of my notation tasks. MUP is available from Arkkra
Enterprises, <TT><A NAME="tex2html6"
  HREF="http://www.Arkkra.com/">http://www.Arkkra.com/</A></TT>.

<P>

<H1><A NAME="SECTION00130000000000000000">
Installing 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT> </A>
</H1>

<P>

<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  is a Python program developed with version 2.7 of Python. At
the very least you will need this version (or later) of Python or any
of the 3.x versions.

<P>
To play the MIDI files you'll need a MIDI player. aplaymidi, tse3play,
and many others are available for Linux systems. For Windows and Mac
systems I'm sure there are many, many choices.

<P>
You'll need a text editor like <SPAN  CLASS="textit">vi</SPAN>, <SPAN  CLASS="textit">emacs</SPAN>, etc. to
create input files. Don't use a word processor!

<P>

<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  consists of a variety of bits and pieces:

<P>

<UL>
<LI>The executable Python script, <TT>mma</TT>,<A NAME="tex2html7"
  HREF="#foot404"><SUP><SPAN CLASS="arabic">1</SPAN>.<SPAN CLASS="arabic">4</SPAN></SUP></A> must somewhere in your
  path. For users running Windows or Mac, please check 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  website
  for details on how to install on these systems. As distributed the
  file ``mma.py'' (and, when installed) ``mma'' are executable scripts
  with the correct permissions already set (this has no effect for
  Windows).

<P>
</LI>
<LI>A number of Python modules (all are files ending in ``.py'').
  These should all be installed under the directory
  <TT><SPAN  CLASS="textbf">/usr/local/share/mma/MMA</SPAN></TT>. See the enclosed file
  <TT><SPAN  CLASS="textbf">INSTALL</SPAN></TT> for some additional commentary.

<P>
</LI>
<LI>A number of library files defining standard rhythms. These
  should all be installed under the directory
  <TT><SPAN  CLASS="textbf">/usr/local/share/mma/lib/stdlib</SPAN></TT>. In addition, the library
  files depend on files in <TT><SPAN  CLASS="textbf">/usr/local/share/mma/includes</SPAN></TT>.

<P>
</LI>
</UL>

<P>
The scripts <TT><SPAN  CLASS="textbf">cp-install</SPAN></TT> or <TT><SPAN  CLASS="textbf">ln-install</SPAN></TT> will install 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT> 
properly on most Linux systems. Both scripts assume that main script
is to be installed in <TT><SPAN  CLASS="textbf">/usr/local/bin</SPAN></TT> and the support files in
<TT><SPAN  CLASS="textbf">/usr/local/share/mma</SPAN></TT>. If you want an alternate location, you
can edit the paths in the script. The only supported alternate to use
is <TT><SPAN  CLASS="textbf">/usr/share/mma</SPAN></TT>.

<P>
The difference between the two scripts is that <TT><SPAN  CLASS="textbf">ln-install</SPAN></TT>
creates symbolic links to the current location; <TT><SPAN  CLASS="textbf">cp-install</SPAN></TT>
copies the files. Which to use it up to you, but if you have unpacked
the distribution in a stable location it is probably easier to use the
link version.

<P>
In addition, you <SPAN  CLASS="textit">can</SPAN> run 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  from the directory created by
the untar. This is not recommended, but will show some of 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT> 's
stuff. In this case you'll have to execute the program file
<TT>mma.py</TT>.

<P>
To run either install script, you should be ``root'' (or at least, you
need write permissions in <TT>/usr/local/</TT>). Use the ``su'' or
``sudo'' command for this.

<P>
If you want to install 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  on a platform other than Linux, please
get the latest updates from our website at <TT><A NAME="tex2html8"
  HREF="www.mellowood.ca/mma">www.mellowood.ca/mma</A></TT>.

<P>

<H1><A NAME="SECTION00140000000000000000">
Running 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT> </A>
</H1>

<P>
For details on the command line operations in 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT> ,
<A HREF="node2.html#sec-running">see the "running" section</A>.

<P>
To create a MIDI file you need to:

<P>

<OL>
<LI>Create a text file (also referred to as the ``input file'') with
  instructions which 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  understands. This includes the chord
  structure of the song, the rhythm to use, the tempo, etc. The file
  can be created with any suitable text editor.<A NAME="tex2html9"
  HREF="#foot405"><SUP><SPAN CLASS="arabic">1</SPAN>.<SPAN CLASS="arabic">5</SPAN></SUP></A>
<P>
</LI>
<LI>Process the input file. From a command line the instruction:

<P>

      <Table Hspace="40%" CellSpacing=0 CellPadding=10 BGColor="OldLace" Border=3>
        <tr><td>
    <B>$ mma myfile &lt;ENTER&gt;  </B> 
   
	    </td></tr>
      </Table>

<P>
will invoke 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  and, assuming no errors are found, create a MIDI
  file <TT><SPAN  CLASS="textbf">myfile.mid</SPAN></TT>.

<P>
</LI>
<LI>Play the MIDI file with any suitable MIDI player.

<P>
</LI>
<LI>Edit the input file again and again until you get the perfect
  track.

<P>
</LI>
<LI>Share any patterns, sequences and grooves with the author so
  they can be included in future releases!
</LI>
</OL>

<P>
An input file consists of the following information:

<P>

<OL>
<LI>
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  directives. These include T<SMALL>EMPO</SMALL>, T<SMALL>IME</SMALL>,
  V<SMALL>OLUME</SMALL>, etc. <A HREF="node29.html#sec-directives">Directives</A>.

<P>
</LI>
<LI>P<SMALL>ATTERN</SMALL>, S<SMALL>EQUENCE</SMALL> and G<SMALL>ROOVE</SMALL> detailed in
  <A HREF="node4.html#sec-pats">Patterns</A>,
  <A HREF="node5.html#sec-seqs">Sequences</A>, and
  <A HREF="node6.html#sec-grooves">Grooves</A>.

<P>
</LI>
<LI>Music information. See <A HREF="node8.html#sec-music">Musical
    Data</A>.

<P>
</LI>
<LI>Comment lines and blank lines. See below.

<P>
</LI>
</OL>

<P>
Items 1 to 3 are detailed later in this manual. Please read them
before you get too involved in this program.

<P>

<H1><A NAME="SECTION00150000000000000000">
Comments</A>
</H1>

<P>
Proper indentation, white space and comments are a <SPAN  CLASS="textit">good
  thing</SPAN>--and you really should use them. But, in most cases 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT> 
really doesn't care:

<P>

<UL>
<LI>Any leading space or tab characters are ignored,

<P>
</LI>
<LI>Multiple tabs and other white space are treated as single
  characters,

<P>
</LI>
<LI>Any blank lines in the input file are ignored.

<P>
</LI>
</UL>

<P>
Each line is initially parsed for comments. A comment is anything
following a ``//'' (2 forward slashes).<A NAME="tex2html10"
  HREF="#foot361"><SUP><SPAN CLASS="arabic">1</SPAN>.<SPAN CLASS="arabic">6</SPAN></SUP></A>
<P>
Multi-line or block comments are also supported by 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT> . A block
comment is started by a ``/*'' and terminated by a
``*/''.<A NAME="tex2html11"
  HREF="#foot363"><SUP><SPAN CLASS="arabic">1</SPAN>.<SPAN CLASS="arabic">7</SPAN></SUP></A> Nesting of block comments is not supported and will
generate unexpected results.

<P>
Both simple and block comments are stripped from the input stream.

<P>
Lines starting with the C<SMALL>OMMENT</SMALL> directive are also ignored (but
not stripped). See the <A HREF="node29.html#comment">comment
  discussion</A> for
details.

<P>

<H1><A NAME="SECTION00160000000000000000">
Theory Of Operation</A>
</H1>

<P>
To understand how 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  works it's easiest to look at the initial
development concept. Initially, a program was wanted which would take
a file which looked something like:

<P>

      <Table Hspace="40%" CellSpacing=0 CellPadding=10 BGColor="OldLace" Border=3>
        <tr><td>
    <B>Tempo 120 
<BR>
Fm 
<BR>
C7 
<BR>  ...</B> 
   
	    </td></tr>
      </Table>

<P>
and end up with a MIDI file which played the specified chords over a
drum track.

<P>
Of course, after starting this ``simple'' project a lot of
complexities developed.

<P>
First, the chord/bar specifications. Just having a single chord per
bar doesn't work--many songs have more than one chord per bar.
Second, what is the rhythm of the chords? What about bass line? Oh,
and where is the drummer?

<P>
Well, things got more complex after that. At a bare minimum, the
program or interface should have the ability to:

<P>

<UL>
<LI>Specify multiple chords per bar,

<P>
</LI>
<LI>Define different patterns for chords, bass lines and drum
  tracks,

<P>
</LI>
<LI>Have easy to create and debug input files,

<P>
</LI>
<LI>Provide a reusable library that a user could simply plug in, or
  modify.

<P>
</LI>
</UL>

<P>
From these simple needs 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  was created.

<P>
The basic building blocks of 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  are P<SMALL>ATTERN</SMALL>s. A pattern is
a specification which tells 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  what notes of a chord to play, the
start point in a bar for the chord/notes, and the duration and the
volume of the notes.

<P>

<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  patterns are combined into S<SMALL>EQUENCE</SMALL>s. This lets you
create multi-bar rhythms.

<P>
A collection of patterns can be saved and recalled as G<SMALL>ROOVE</SMALL>s.
This makes it easy to pre-define complex rhythms in library files and
incorporate them into your song with a simple two word command.

<P>

<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  is bar or measure based (we use the words interchangeably in
this document). This means that 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  processes your song one bar at
a time. The music specification lines all assume that you are
specifying a single bar of music. The number of beats per bar can be
adjusted; however, all chord changes must fall on a beat division (the
playing of the chord or drum note can occur anywhere in the bar).

<P>
To make the input files look more musical, 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  supports
R<SMALL>EPEAT</SMALL>s and R<SMALL>EPEAT</SMALL>E<SMALL>NDING</SMALL>s. However, complexities like
<SPAN  CLASS="textit">D.S.</SPAN> and <SPAN  CLASS="textit">Coda</SPAN> are not internally supported (but can be
created by using the G<SMALL>OTO</SMALL> command).

<P>

<H1><A NAME="SECTION00170000000000000000">
Case Sensitivity</A>
</H1>

<P>
Just about everything in a 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  file is case insensitive.

<P>
This means that the command:

<P>

      <Table Hspace="40%" CellSpacing=0 CellPadding=10 BGColor="OldLace" Border=3>
        <tr><td>
    <B>Tempo 120  </B> 
   
	    </td></tr>
      </Table>

<P>
could be entered in your file as:

<P>

      <Table Hspace="40%" CellSpacing=0 CellPadding=10 BGColor="OldLace" Border=3>
        <tr><td>
    <B>TEMPO 120  </B> 
   
	    </td></tr>
      </Table>

<P>
or even

<P>

      <Table Hspace="40%" CellSpacing=0 CellPadding=10 BGColor="OldLace" Border=3>
        <tr><td>
    <B>TeMpO 120  </B> 
   
	    </td></tr>
      </Table>

<P>
for the exact same results.

<P>
Names for patterns, and grooves are also case insensitive.

<P>
The only exceptions are the names for chords, notes in S<SMALL>OLO</SMALL>s,
and filenames. In keeping with standard chord notation, chord names
are in mixed case; this is detailed in <A HREF="node8.html#sec-music">Musical
  Data</A>. Filenames are covered in
<A HREF="node32.html#sec-paths">Paths and Filenames</A>.

<P>
<BR><HR><H4>Footnotes</H4>
<DL>
<DT><A NAME="foot223">...,</A><A
 HREF="node1.html#tex2html1"><SUP><SPAN CLASS="arabic">1</SPAN>.<SPAN CLASS="arabic">1</SPAN></SUP></A></DT>
<DD>Musical MIDI
  Accompaniment and the short form 
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  in the distinctive script
  are names for a program written by Bob van der Poel. The ``MIDI
  Manufacturers Association, Inc.'' uses the acronym MMA, but there is
  no association between the two.

</DD>
<DT><A NAME="foot213">...
MIDI</A><A
 HREF="node1.html#tex2html2"><SUP><SPAN CLASS="arabic">1</SPAN>.<SPAN CLASS="arabic">2</SPAN></SUP></A></DT>
<DD>MIDI is an acronym for Musical Instrument Digital
  Interface.

</DD>
<DT><A NAME="foot259">... perspectives.</A><A
 HREF="node1.html#tex2html4"><SUP><SPAN CLASS="arabic">1</SPAN>.<SPAN CLASS="arabic">3</SPAN></SUP></A></DT>
<DD>The problem, all humor aside, is
  that the viewpoints of a program's author and user are quite
  different. The two ``see'' problems and solutions differently, and
  for a user manual the programmer's view is not the best.

</DD>
<DT><A NAME="foot404">...mma,</A><A
 HREF="node1.html#tex2html7"><SUP><SPAN CLASS="arabic">1</SPAN>.<SPAN CLASS="arabic">4</SPAN></SUP></A></DT>
<DD>In the
    distribution this is <TT>mma.py</TT>. It is renamed to save a few
    keystrokes when entering the command.

</DD>
<DT><A NAME="foot405">... editor.</A><A
 HREF="node1.html#tex2html9"><SUP><SPAN CLASS="arabic">1</SPAN>.<SPAN CLASS="arabic">5</SPAN></SUP></A></DT>
<DD>
<FONT Face="Serif"  Color="Navy"><I>MMA</I></FONT>  is
    pretty open about the ``encoding'' of the file, but to keep Python
    3.x happy you should use ``cp1252'' (a standard Windows format).

</DD>
<DT><A NAME="foot361">... slashes).</A><A
 HREF="node1.html#tex2html10"><SUP><SPAN CLASS="arabic">1</SPAN>.<SPAN CLASS="arabic">6</SPAN></SUP></A></DT>
<DD>The first choice for
  a comment character was a single ``#'', but that sign is used for
  ``sharps'' in chord notation.

</DD>
<DT><A NAME="foot363">...
``*/''.</A><A
 HREF="node1.html#tex2html11"><SUP><SPAN CLASS="arabic">1</SPAN>.<SPAN CLASS="arabic">7</SPAN></SUP></A></DT>
<DD>These symbols are used in many other languages, most
  notably ``C''.

</DD>
</DL>
<DIV CLASS="navigation"><HR>
<!--Navigation Panel-->
<A NAME="tex2html458"
  HREF="node2.html">
<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next.png"></A> 
<A NAME="tex2html456"
  HREF="mma.html">
<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up.png"></A> 
<A NAME="tex2html450"
  HREF="mma.html">
<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="prev.png"></A>   
<BR>
<B> Next:</B> <A NAME="tex2html459"
  HREF="node2.html">Running</A>
<B> Up:</B> <A NAME="tex2html457"
  HREF="mma.html">Reference Manual</A>
<B> Previous:</B> <A NAME="tex2html451"
  HREF="mma.html">Reference Manual</A></DIV>
<!--End of Navigation Panel-->
<ADDRESS>
Bob van der Poel
2016-06-11
</ADDRESS>
</BODY>
</HTML>