Yoruba vowels

Standard Yoruba has seven oral vowels, /i e ɛ a ɔ o u/, the mid-only tongue-root system of Casali's typology, analyzed by Archangeli and Pulleyblank: the mid vowels pair, /e o/ [+ATR] against /ɛ ɔ/ [−ATR], while the high vowels /i u/ are [+ATR] and the low vowel /a/ [−ATR] without counterparts. Non-high vowels in a word agree in [ATR]. The nasal vowels are not represented.

The feature values come from the PHOIBLE chart, which codes the tongue-root contrast by [tense], so a vowel is the segment of its chart entry's tongue-root reading.

Main definitions

• Yoruba.vowel: the segment of a vowel's chart entry, with [tense] read as [ATR].
• Yoruba.i, Yoruba.epsilon and the like: the seven vowels, and Yoruba.vowels the set of them.

Main results

• Yoruba.subset_yor: the vowels are those of PHOIBLE's Yoruba inventory.
• Yoruba.hasValue_atr_iff: the advanced vowels are /i e o u/.

References

• [Cas03]
• [AP89]
• [MMcC19]

def Yoruba.vowel (m : Data.PHOIBLE.FeatureMatrix) : Phonology.Segment

A vowel is the segment of its chart entry's tongue-root reading.

Equations

• Yoruba.vowel m = Phonology.Segment.ofChart m.tenseAsATR

def Yoruba.i : Phonology.Segment

The high front vowel /i/.

Equations

• Yoruba.i = Yoruba.vowel Data.PHOIBLE.FeatureMatrix.i

def Yoruba.e : Phonology.Segment

The advanced mid front vowel /e/.

Equations

• Yoruba.e = Yoruba.vowel Data.PHOIBLE.FeatureMatrix.e

def Yoruba.epsilon : Phonology.Segment

The unadvanced mid front vowel /ɛ/.

Equations

• Yoruba.epsilon = Yoruba.vowel Data.PHOIBLE.FeatureMatrix.«ɛ»

def Yoruba.a : Phonology.Segment

The low vowel /a/.

Equations

• Yoruba.a = Yoruba.vowel Data.PHOIBLE.FeatureMatrix.a

def Yoruba.openO : Phonology.Segment

The unadvanced mid back vowel /ɔ/.

Equations

• Yoruba.openO = Yoruba.vowel Data.PHOIBLE.FeatureMatrix.«ɔ»

def Yoruba.o : Phonology.Segment

The advanced mid back vowel /o/.

Equations

• Yoruba.o = Yoruba.vowel Data.PHOIBLE.FeatureMatrix.o

def Yoruba.u : Phonology.Segment

The high back vowel /u/.

Equations

• Yoruba.u = Yoruba.vowel Data.PHOIBLE.FeatureMatrix.u

def Yoruba.vowels : Finset Phonology.Segment

The seven oral vowels, pairwise distinct.

Equations

• Yoruba.vowels = { val := ↑[Yoruba.i, Yoruba.e, Yoruba.epsilon, Yoruba.a, Yoruba.openO, Yoruba.o, Yoruba.u], nodup := Yoruba.vowels._proof_1 }

theorem Yoruba.subset_yor : vowels ⊆ Finset.image vowel Data.PHOIBLE.Inventories.Yoruba.yor.featureMatrices

The vowels are those of PHOIBLE's Yoruba inventory.

theorem Yoruba.hasValue_atr_iff (x : Phonology.Segment) : x ∈ vowels → (x.HasValue Phonology.Feature.atr true ↔ x ∈ {i, e, o, u})

The advanced vowels are /i e o u/.