OddCliffordNumber constructor now fails to convert arbitrary scalars

CHANGELOG.md

@@ -7,6 +7,10 @@ adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
 
+### Fixed
+  - `OddCliffordNumber` constructors now fail to operate on scalars unless there is exactly one odd
+    element in the algebra.
+
 ## [0.1.6] - 2024-06-27
 
 ### Added

src/even.jl

@@ -57,6 +57,17 @@ end
 # Convert real/complex numbers to CliffordNumber
 (::Type{T})(x::BaseNumber) where {T<:Z2CliffordNumber} = T(ntuple(i -> x*isone(i), Val(nblades(T))))
 
+function (::Type{T})(x::BaseNumber) where {T<:OddCliffordNumber}
+    isone(nblades(T)) && return T(ntuple(i -> x*isone(i), Val(nblades(T))))
+    throw(
+        DomainError(
+            x,
+            "An OddCliffordNumber cannot be constructed from a scalar unless the algebra " *
+            "contains exactly one odd element."
+        )
+    )
+end
+
 #---Number of elements-----------------------------------------------------------------------------#
 
 nblades(::Type{<:Z2CliffordNumber{P,Q}}) where {P,Q} = div(blade_count(Q), 2)

test/construction.jl

@@ -60,6 +60,9 @@ end
     k2 = KVector{2,VGA(3)}(1, 2, 3)
     @test CliffordNumber{VGA(3)}(1337) === CliffordNumber{VGA(3)}(1337, 0, 0, 0, 0, 0, 0, 0)
     @test EvenCliffordNumber{VGA(3)}(1337) === EvenCliffordNumber{VGA(3)}(1337, 0, 0, 0)
+    # If there is more than one odd element of the subalgebra, this should throw
+    @test_throws DomainError OddCliffordNumber{VGA(3)}(1337)
+    @test OddCliffordNumber{VGA(1)}(1337) == KVector{1,VGA(1)}(1337)
     # Mixed types in input
     @test CliffordNumber{VGA(3)}(0.0, 0, 0, 0, 0, 0, 0, 0) === zero(CliffordNumber{VGA(3),Float64})
     @test CliffordNumber{VGA(3)}(0, 0, 0, 0, 0, 0, 0, 0.0) === zero(CliffordNumber{VGA(3),Float64})