N.CS lookup tables and documentation/help errors

[dstroud]

Please describe the bug.

1. N.CS lookup values are in a different order depending on where we look:

N.CS	N.CS Documentation	N.CS Help	N.S
Major	Major	Major	Major
Natural Minor	Natural Minor	Natural Minor	Natural Minor
Harmonic Minor	Harmonic Minor	Harmonic Minor	Harmonic Minor
Melodic Minor	Melodic Minor	Melodic Minor	Melodic Minor
Dorian	Dorian	Dorian	Dorian
Phrygian	Phrygian	Phrygian	Phrygian
Lydian	Lydian	Lydian	Lydian
Locrian	Myxolidian	Locrian	Myxolidian
Myxolidian	Locrian	Myxolidian	Locrian

2. The documentation has the wrong chord indices listed for the 'myxolidian' entry. Instead of {6, 0, 1, 1, 0, 2, 1} it should be {2, 1, 6, 0, 1, 1, 0}. The Locrian entry has the correct indices but the N.CS op does not work as expected due to issue # 1.

3. AFAIK, the conventional spelling is 'mixolydian' rather than 'myxolidian'. This might be a good opportunity to update.

I propose a fix involving changing the order of the scales to be consistent with N.S and fixing the documentation to have the correct indices.

Please include the hash displayed at startup and the release of the software (e.g. "Teletype v2.0.1 5f838c9")

I've reproduced the issue on Teletype I2M Beta 2 but it appears present in the sources below.

What steps are required to reproduce the bug?

See the following:

teletype/src/table.c

Lines 134 to 145 in 79db601

	// chord scales for N.CS op - values are indices into table_n_c
	const uint8_t table_n_cs[9][7] = {
	{ 0, 1, 1, 0, 2, 1, 6 }, // Major
	{ 1, 6, 0, 1, 1, 0, 2 }, // Natural Minor
	{ 8, 6, 7, 1, 2, 0, 3 }, // Harmonic Minor
	{ 8, 1, 7, 2, 2, 6, 6 }, // Melodic Minor
	{ 1, 1, 0, 2, 1, 6, 0 }, // Dorian
	{ 1, 0, 2, 1, 6, 0, 1 }, // Phrygian
	{ 0, 2, 1, 6, 0, 1, 1 }, // Lydian
	{ 6, 0, 1, 1, 0, 2, 1 }, // Locrian
	{ 2, 1, 6, 0, 1, 1, 0 }, // Myxolydian
	};

teletype/docs/ops/maths.toml

Lines 464 to 473 in f6bc024

	Chord Scales - Refer to chord indices in `N.C` OP
	- `0` = Major `{0, 1, 1, 0, 2, 1, 6}`
	- `1` = Natural Minor `{1, 6, 0, 1, 1, 0, 2}`
	- `2` = Harmonic Minor `{8, 6, 7, 1, 2, 0, 3}`
	- `3` = Melodic Minor `{8, 1, 7, 2, 2, 6, 6}`
	- `4` = Dorian `{1, 1, 0, 2, 1, 6, 0}`
	- `5` = Phrygian `{1, 0, 2, 1, 6, 0, 1}`
	- `6` = Lydian `{0, 2, 1, 6, 0, 1, 1}`
	- `7` = Myxolidian `{6, 0, 1, 1, 0, 2, 1}`
	- `8` = Locrian `{6, 0, 1, 1, 0, 2, 1}`

teletype/module/help_mode.c

Lines 246 to 264 in f6bc024

	"CHORD SCALE NOTE OP - N.CS",
	"N.CS R S D C",
	" R = ROOT (0-127)",
	" S = SCALE (0-8) *",
	" D = SCALE DEGREE (1-7) *",
	" C = CHORD COMPONENT (0-3) *",
	" * S, D, C WILL WRAP",
	" NEGATIVE INDEXING OK",
	" SCALES - SEE CHORDS ABOVE",
	" MAJ = 0, 1, 1, 0, 2, 1, 6",
	" NMI = 1, 6, 0, 1, 1, 0, 2",
	" HMI = 8, 6, 7, 1, 2, 0, 3",
	" MMI = 8, 1, 7, 2, 2, 6, 6",
	" DOR = 1, 1, 0, 2, 1, 6, 0",
	" PHR = 1, 0, 2, 1, 6, 0, 1",
	" LYD = 0, 2, 1, 6, 0, 1, 1",
	" LOC = 6, 0, 1, 1, 0, 2, 1",
	" MYX = 2, 1, 6, 0, 1, 1, 0",
	" RETURNS N TABLE VALUE" };