Fix augmented third

src/Chord.hs

@@ -20,6 +20,7 @@ module Chord
   , majorSus4
   , Chord.majorSixth
   , dominantSeventh
+  , diminishedTriad
   , augmentedTriad
   , augmentedSeventh
   , minorTriad
@@ -96,10 +97,13 @@ diminishedSeventh :: ChordType
 diminishedSeventh = Chord.majorSixth -- under equal temperament
 
 dominantSeventh :: ChordType
-dominantSeventh = chordType "dim" [unison, majorThird, perfectFifth, I.minorSeventh]
+dominantSeventh = chordType "dim7" [unison, majorThird, perfectFifth, I.minorSeventh]
+
+diminishedTriad :: ChordType
+diminishedTriad = chordType "dim" [unison, minorThird, diminishedFifth]
 
 augmentedTriad :: ChordType
-augmentedTriad = chordType "aug" [unison, minorThird, augmentedFifth]
+augmentedTriad = chordType "aug" [unison, majorThird, augmentedFifth]
 
 augmentedSeventh :: ChordType
 augmentedSeventh = chordType "aug7" [unison, minorThird, augmentedFifth, I.minorSeventh]

src/Interval.hs

@@ -64,6 +64,9 @@ perfectFourth = Interval 5
 tritone :: Interval
 tritone = Interval 6
 
+diminishedFifth :: Interval
+diminishedFifth = Interval 6
+
 perfectFifth :: Interval
 perfectFifth = Interval 7