Fix number_eltype(Vector{Vector{Float64}}) (#179)

* Fix number_eltype(Vector{Vector{Float64}})

* number, not real

NEWS.md

@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.15.6] 15/12/2023
+
+### Fixed
+
+* `number_eltype` correctly returns scalar type for nested array types like `number_eltype(Vector{Vector{Float64}})`.
+
 ## [0.15.5] 13/12/2023
 
 ### Added

Project.toml

@@ -1,7 +1,7 @@
 name = "ManifoldsBase"
 uuid = "3362f125-f0bb-47a3-aa74-596ffd7ef2fb"
 authors = ["Seth Axen <[email protected]>", "Mateusz Baran <[email protected]>", "Ronny Bergmann <[email protected]>", "Antoine Levitt <[email protected]>"]
-version = "0.15.5"
+version = "0.15.6"
 
 [deps]
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"

src/ManifoldsBase.jl

@@ -824,6 +824,12 @@ number_eltype(x) = eltype(x)
     return typeof(mapreduce(eti -> one(number_eltype(eti)), +, x))
 end
 @inline number_eltype(::AbstractArray{T}) where {T<:Number} = T
+@inline function number_eltype(::Type{<:AbstractArray{T}}) where {T}
+    return number_eltype(T)
+end
+@inline function number_eltype(::Type{<:AbstractArray{T}}) where {T<:Number}
+    return T
+end
 @inline function number_eltype(x::Tuple)
     @inline eti_to_one(eti) = one(number_eltype(eti))
     return typeof(sum(map(eti_to_one, x)))

test/allocation.jl

@@ -65,6 +65,7 @@ ManifoldsBase.representation_size(::AllocManifold3) = (2, 3)
     @test number_eltype(([2], [3.0])) === Float64
     @test number_eltype(([2], [3])) === Int
     @test number_eltype(Any[[2.0], [3.0]]) === Float64
+    @test number_eltype(typeof([[1.0, 2.0]])) === Float64
 
     alloc2 = ManifoldsBase.allocate_result(AllocManifold2(), rand)
     @test alloc2 isa Matrix{Float64}