25 lines
507 B
Go
25 lines
507 B
Go
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// Copyright 2014 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// +build !go1.4
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package exact
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import (
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"math"
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"math/big"
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)
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func ratToFloat32(x *big.Rat) (float32, bool) {
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// Before 1.4, there's no Rat.Float32.
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// Emulate it, albeit at the cost of
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// imprecision in corner cases.
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x64, exact := x.Float64()
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x32 := float32(x64)
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if math.IsInf(float64(x32), 0) {
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exact = false
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}
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return x32, exact
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}
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