Fix type promotion with units (#52)

* fix Float32 promote

* v0.5

Author: JeffFessler

Project.toml

@@ -1,7 +1,7 @@
 name = "ImagePhantoms"
 uuid = "71a99df6-f52c-4da1-bd2a-69d6f37f3252"
 authors = ["Jeff Fessler <[email protected]> and contributors"]
-version = "0.4.0"
+version = "0.5.0"
 
 [deps]
 LazyGrids = "7031d0ef-c40d-4431-b2f8-61a8d2f650db"

src/object.jl

@@ -239,5 +239,5 @@ Determine the element type of the Radon transform of an object
 Ensures that its precision is at least `Float32`.
 """
 function radon_type(::Object{S, D, V, C, A}) where {S, D, V <: Number, C <: RealU, A <: RealU}
-    return eltype(oneunit(C) * oneunit(V) * one(A) * one(Float32))
+    return eltype(oneunit(C) * oneunit(V) * one(A) * 1f0) # at least Float32
 end

src/object2.jl

@@ -85,7 +85,7 @@ function phantom(
     y::AbstractVector,
     oa::Array{<:Object2d},
     oversample::Int ;
-    T::DataType = promote_type(eltype.(oa)..., Float32),
+    T::DataType = eltype(1f0 * oneunit(promote_type(eltype.(oa)...))),
 )
 
     oversample < 1 && throw(ArgumentError("oversample $oversample"))

src/object3.jl

@@ -90,7 +90,7 @@ function phantom(
     z::AbstractVector,
     oa::Array{<:Object3d{S,V}},
     oversample::Int;
-    T::DataType = promote_type(V, Float32),
+    T::DataType = eltype(oneunit(V) * 1f0), # at least Float32
 ) where {S, V <: Number}
 
     oversample < 1 && throw(ArgumentError("oversample $oversample"))