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stevengjstevengj
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max and min of NaN return NaN (closes #7866) (fixes #12552)
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‎NEWS.md

+3
Original file line numberDiff line numberDiff line change
@@ -31,6 +31,8 @@ This section lists changes that do not have deprecation warnings.
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Library improvements
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--------------------
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* `max`, `min`, and related functions (`minmax`, `maximum`, `minimum`, `extrema`) now return `NaN` for `NaN` arguments ([#12563]).
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Compiler/Runtime improvements
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-----------------------------
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@@ -551,6 +553,7 @@ Language tooling improvements
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[#11242]: https://github.com/JuliaLang/julia/issues/11242
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[#11688]: https://github.com/JuliaLang/julia/issues/11688
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[#12231]: https://github.com/JuliaLang/julia/issues/12231
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[#12563]: https://github.com/JuliaLang/julia/issues/12563
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[#12819]: https://github.com/JuliaLang/julia/issues/12819
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[#12872]: https://github.com/JuliaLang/julia/issues/12872
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[#13062]: https://github.com/JuliaLang/julia/issues/13062

‎base/math.jl

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Original file line numberDiff line numberDiff line change
@@ -314,16 +314,15 @@ atan2(y::Float64, x::Float64) = ccall((:atan2,libm), Float64, (Float64, Float64,
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atan2(y::Float32, x::Float32) = ccall((:atan2f,libm), Float32, (Float32, Float32), y, x)
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max{T<:AbstractFloat}(x::T, y::T) = ifelse((y > x) | (signbit(y) < signbit(x)),
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ifelse(isnan(y), x, y), ifelse(isnan(x), y, x))
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ifelse(isnan(x), x, y), ifelse(isnan(y), y, x))
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min{T<:AbstractFloat}(x::T, y::T) = ifelse((y < x) | (signbit(y) > signbit(x)),
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ifelse(isnan(y), x, y), ifelse(isnan(x), y, x))
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ifelse(isnan(x), x, y), ifelse(isnan(y), y, x))
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minmax{T<:AbstractFloat}(x::T, y::T) = ifelse(isnan(x-y), ifelse(isnan(x), (y, y), (x, x)),
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ifelse((y < x) | (signbit(y) > signbit(x)), (y, x),
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ifelse((y > x) | (signbit(y) < signbit(x)), (x, y),
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ifelse(x == x, (x, x), (y, y)))))
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minmax{T<:AbstractFloat}(x::T, y::T) =
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ifelse(isnan(x) | isnan(y), ifelse(isnan(x), (x,x), (y,y)),
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ifelse((y > x) | (signbit(x) > signbit(y)), (x,y), (y,x)))
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"""

‎base/mpfr.jl

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@@ -584,12 +584,16 @@ function log1p(x::BigFloat)
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end
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function max(x::BigFloat, y::BigFloat)
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isnan(x) && return x
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isnan(y) && return y
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z = BigFloat()
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ccall((:mpfr_max, :libmpfr), Int32, (Ptr{BigFloat}, Ptr{BigFloat}, Ptr{BigFloat}, Int32), &z, &x, &y, ROUNDING_MODE[])
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return z
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end
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function min(x::BigFloat, y::BigFloat)
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isnan(x) && return x
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isnan(y) && return y
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z = BigFloat()
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ccall((:mpfr_min, :libmpfr), Int32, (Ptr{BigFloat}, Ptr{BigFloat}, Ptr{BigFloat}, Int32), &z, &x, &y, ROUNDING_MODE[])
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return z

‎base/reduce.jl

+3-11
Original file line numberDiff line numberDiff line change
@@ -503,19 +503,11 @@ function extrema(itr)
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s = start(itr)
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done(itr, s) && throw(ArgumentError("collection must be non-empty"))
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(v, s) = next(itr, s)
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while v != v && !done(itr, s)
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(x, s) = next(itr, s)
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v = x
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end
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vmin = v
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vmax = v
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vmin = vmax = v
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while !done(itr, s)
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(x, s) = next(itr, s)
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if x > vmax
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vmax = x
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elseif x < vmin
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vmin = x
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end
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vmax = max(x, vmax)
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vmin = min(x, vmin)
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end
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return (vmin, vmax)
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end

‎test/mpfr.jl

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Original file line numberDiff line numberDiff line change
@@ -301,8 +301,8 @@ y = BigFloat(2)
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@test max(x,y) == x
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@test min(x,y) == y
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y = BigFloat(NaN)
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@test max(x,y) == x
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@test min(x,y) == x
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@test isnan(max(x,y))
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@test isnan(min(x,y))
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@test isnan(max(y,y))
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@test isnan(min(y,y))
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‎test/numbers.jl

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@@ -54,35 +54,41 @@
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@test 2.0 * 3.0 == 6.
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@test min(1.0,1) == 1
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57+
const ≅ = isequal # convenient for comparing NaNs
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# min, max and minmax
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@test min(1) === 1
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@test max(1) === 1
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@test minmax(1) === (1, 1)
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@test minmax(5, 3) == (3, 5)
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@test minmax(3., 5.) == (3., 5.)
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@test minmax(5., 3.) == (3., 5.)
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@test minmax(3., NaN) == (3., 3.)
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@test minmax(NaN, 3.) == (3., 3.)
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@test isequal(minmax(NaN, NaN), (NaN, NaN))
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@test minmax(3., NaN) ≅ (NaN, NaN)
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@test minmax(NaN, 3) ≅ (NaN, NaN)
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@test minmax(Inf, NaN) ≅ (NaN, NaN)
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@test minmax(NaN, Inf) ≅ (NaN, NaN)
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@test minmax(-Inf, NaN) ≅ (NaN, NaN)
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@test minmax(NaN, -Inf) ≅ (NaN, NaN)
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@test minmax(NaN, NaN) ≅ (NaN, NaN)
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@test min(-0.0,0.0) === min(0.0,-0.0)
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@test max(-0.0,0.0) === max(0.0,-0.0)
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@test minmax(-0.0,0.0) === minmax(0.0,-0.0)
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@test max(-3.2, 5.1) == max(5.1, -3.2) == 5.1
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@test min(-3.2, 5.1) == min(5.1, -3.2) == -3.2
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@test max(-3.2, Inf) == max(Inf, -3.2) == Inf
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@test max(-3.2, NaN) == max(NaN, -3.2) == -3.2
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@test max(-3.2, NaN) ≅ max(NaN, -3.2) ≅ NaN
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@test min(5.1, Inf) == min(Inf, 5.1) == 5.1
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@test min(5.1, -Inf) == min(-Inf, 5.1) == -Inf
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@test min(5.1, NaN) == min(NaN, 5.1) == 5.1
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@test min(5.1, -NaN) == min(-NaN, 5.1) == 5.1
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@test min(5.1, NaN) ≅ min(NaN, 5.1) ≅ NaN
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@test min(5.1, -NaN) ≅ min(-NaN, 5.1) ≅ NaN
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@test minmax(-3.2, 5.1) == (min(-3.2, 5.1), max(-3.2, 5.1))
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@test minmax(-3.2, Inf) == (min(-3.2, Inf), max(-3.2, Inf))
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@test minmax(-3.2, NaN) == (min(-3.2, NaN), max(-3.2, NaN))
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@test (max(Inf,NaN), max(-Inf,NaN), max(Inf,-NaN), max(-Inf,-NaN)) == (Inf, -Inf, Inf, -Inf)
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@test (max(NaN,Inf), max(NaN,-Inf), max(-NaN,Inf), max(-NaN,-Inf)) == (Inf, -Inf, Inf, -Inf)
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@test (min(Inf,NaN), min(-Inf,NaN), min(Inf,-NaN), min(-Inf,-NaN)) == (Inf, -Inf, Inf, -Inf)
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@test (min(NaN,Inf), min(NaN,-Inf), min(-NaN,Inf), min(-NaN,-Inf)) == (Inf, -Inf, Inf, -Inf)
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@test minmax(-Inf,NaN) == (min(-Inf,NaN), max(-Inf,NaN))
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@test minmax(-3.2, NaN) ≅ (min(-3.2, NaN), max(-3.2, NaN))
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@test (max(Inf,NaN), max(-Inf,NaN), max(Inf,-NaN), max(-Inf,-NaN)) ≅ (NaN,NaN,NaN,NaN)
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@test (max(NaN,Inf), max(NaN,-Inf), max(-NaN,Inf), max(-NaN,-Inf)) ≅ (NaN,NaN,NaN,NaN)
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@test (min(Inf,NaN), min(-Inf,NaN), min(Inf,-NaN), min(-Inf,-NaN)) ≅ (NaN,NaN,NaN,NaN)
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@test (min(NaN,Inf), min(NaN,-Inf), min(-NaN,Inf), min(-NaN,-Inf)) ≅ (NaN,NaN,NaN,NaN)
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@test minmax(-Inf,NaN) ≅ (min(-Inf,NaN), max(-Inf,NaN))
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# fma
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let x = Int64(7)^7

‎test/reduce.jl

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@@ -144,13 +144,13 @@ prod2(itr) = invoke(prod, Tuple{Any}, itr)
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@test isnan(minimum([NaN]))
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@test isequal(extrema([NaN]), (NaN, NaN))
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147-
@test maximum([NaN, 2., 3.]) == 3.
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@test minimum([NaN, 2., 3.]) == 2.
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@test extrema([NaN, 2., 3.]) == (2., 3.)
147+
@test isnan(maximum([NaN, 2., 3.]))
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@test isnan(minimum([NaN, 2., 3.]))
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@test isequal(extrema([NaN, 2., 3.]), (NaN,NaN))
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151-
@test maximum([4., 3., NaN, 5., 2.]) == 5.
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@test minimum([4., 3., NaN, 5., 2.]) == 2.
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@test extrema([4., 3., NaN, 5., 2.]) == (2., 5.)
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@test isnan(maximum([4., 3., NaN, 5., 2.]))
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@test isnan(minimum([4., 3., NaN, 5., 2.]))
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@test isequal(extrema([4., 3., NaN, 5., 2.]), (NaN,NaN))
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@test maxabs(Int[]) == 0
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@test_throws ArgumentError Base.minabs(Int[])

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