Add: julia-0.6.2

Former-commit-id: ccc667cf67d569f3fb3df39aa57c2134755a7551

julia-0.6.2/share/julia/test/rounding.jl

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+# This file is a part of Julia. License is MIT: https://julialang.org/license
+
+# Small sanity tests to ensure changing the rounding of float functions work
+using Base.Test
+
+## Float64 checks
+# a + b returns a number exactly between prevfloat(1.) and 1., so its
+# final result depends strongly on the utilized rounding direction.
+a = prevfloat(0.5)
+b = 0.5
+c = 0x1p-54
+d = prevfloat(1.)
+
+# Default rounding direction, RoundNearest
+@test a + b === 1.
+@test - a - b === -1.
+@test a - b === -c
+@test b - a === c
+
+# RoundToZero
+setrounding(Float64,RoundToZero) do
+    @test a + b === d
+    @test - a - b === -d
+    @test a - b === -c
+    @test b - a === c
+end
+
+# Sanity check to see if we have returned to RoundNearest
+@test a + b === 1.
+@test - a - b === -1.
+@test a - b == -c
+@test b - a == c
+
+# RoundUp
+setrounding(Float64,RoundUp) do
+    @test a + b === 1.
+    @test - a - b === -d
+    @test a - b === -c
+    @test b - a === c
+end
+
+# RoundDown
+setrounding(Float64,RoundDown) do
+    @test a + b === d
+    @test - a - b === -1.
+    @test a - b === -c
+    @test b - a === c
+end
+
+## Float32 checks
+
+a32 = prevfloat(0.5f0)
+b32 = 0.5f0
+c32 = (1.f0 - prevfloat(1.f0))/2
+d32 = prevfloat(1.0f0)
+
+# Default rounding direction, RoundNearest
+@test a32 + b32 === 1.0f0
+@test - a32 - b32 === -1.0f0
+@test a32 - b32 === -c32
+@test b32 - a32 === c32
+
+# RoundToZero
+setrounding(Float32,RoundToZero) do
+    @test a32 + b32 === d32
+    @test - a32 - b32 === -d32
+    @test a32 - b32 === -c32
+    @test b32 - a32 === c32
+end
+
+# Sanity check to see if we have returned to RoundNearest
+@test a32 + b32 === 1.0f0
+@test - a32 - b32 === -1.0f0
+@test a32 - b32 == -c32
+@test b32 - a32 == c32
+
+# RoundUp
+setrounding(Float32,RoundUp) do
+    @test a32 + b32 === 1.0f0
+    @test - a32 - b32 === -d32
+    @test a32 - b32 === -c32
+    @test b32 - a32 === c32
+end
+
+# RoundDown
+setrounding(Float32,RoundDown) do
+    @test a32 + b32 === d32
+    @test - a32 - b32 === -1.0f0
+    @test a32 - b32 === -c32
+    @test b32 - a32 === c32
+end
+
+# convert with rounding
+for v = [sqrt(2),-1/3,nextfloat(1.0),prevfloat(1.0),nextfloat(-1.0),
+         prevfloat(-1.0),nextfloat(0.0),prevfloat(0.0)]
+    pn = Float32(v,RoundNearest)
+    @test pn == convert(Float32,v)
+    pz = Float32(v,RoundToZero)
+    @test pz == setrounding(()->convert(Float32,v), Float64, RoundToZero)
+    pd = Float32(v,RoundDown)
+    @test pd == setrounding(()->convert(Float32,v), Float64, RoundDown)
+    pu = Float32(v,RoundUp)
+    @test pu == setrounding(()->convert(Float32,v), Float64, RoundUp)
+
+    @test pn == pd || pn == pu
+    @test v > 0 ? pz == pd : pz == pu
+    @test pu - pd == eps(pz)
+end
+
+for T in [Float32,Float64]
+    for v in [sqrt(big(2.0)),-big(1.0)/big(3.0),nextfloat(big(1.0)),
+              prevfloat(big(1.0)),nextfloat(big(0.0)),prevfloat(big(0.0)),
+              pi,e,eulergamma,catalan,golden,
+              typemax(Int64),typemax(UInt64),typemax(Int128),typemax(UInt128),0xa2f30f6001bb2ec6]
+        pn = T(v,RoundNearest)
+        @test pn == convert(T,BigFloat(v))
+        pz = T(v,RoundToZero)
+        @test pz == setrounding(()->convert(T,BigFloat(v)), BigFloat, RoundToZero)
+        pd = T(v,RoundDown)
+        @test pd == setrounding(()->convert(T,BigFloat(v)), BigFloat, RoundDown)
+        pu = T(v,RoundUp)
+        @test pu == setrounding(()->convert(T,BigFloat(v)), BigFloat, RoundUp)
+
+        @test pn == pd || pn == pu
+        @test v > 0 ? pz == pd : pz == pu
+        @test isinf(pu) || pu - pd == eps(pz)
+    end
+end
+
+#fenv
+@test Base.Rounding.from_fenv(Base.Rounding.to_fenv(RoundNearest)) == RoundNearest
+@test Base.Rounding.from_fenv(Base.Rounding.to_fenv(RoundToZero)) == RoundToZero
+@test Base.Rounding.from_fenv(Base.Rounding.to_fenv(RoundUp)) == RoundUp
+@test Base.Rounding.from_fenv(Base.Rounding.to_fenv(RoundDown)) == RoundDown
+@test_throws ArgumentError Base.Rounding.from_fenv(-99)
+
+badness = 1//0
+@test_throws DivideError round(Int64,badness,RoundNearestTiesAway)
+@test_throws DivideError round(Int64,badness,RoundNearestTiesUp)