41 lines
1.0 KiB
Go
41 lines
1.0 KiB
Go
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package value
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import (
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"math"
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)
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const (
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// NormalNaN is a quiet NaN. This is also math.NaN().
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NormalNaN uint64 = 0x7ff8000000000001
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// StaleNaN is a signalling NaN, due to the MSB of the mantissa being 0.
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// This value is chosen with many leading 0s, so we have scope to store more
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// complicated values in the future. It is 2 rather than 1 to make
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// it easier to distinguish from the NormalNaN by a human when debugging.
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StaleNaN uint64 = 0x7ff0000000000002
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)
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// IsNaN checks if the value is nan
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func IsNaN(v float64) bool {
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return math.Float64bits(v) == NormalNaN
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}
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// IsStaleNaN returns true when the provided NaN value is a stale marker.
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func IsStaleNaN(v float64) bool {
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return math.Float64bits(v) == StaleNaN
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}
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// Float64 returns a pointer to the float64 value passed in.
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func Float64(v float64) *float64 {
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return &v
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}
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// Float64Value returns the value of the float64 pointer passed in or
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// 0 if the pointer is nil.
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func Float64Value(v *float64) float64 {
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if v != nil {
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return *v
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}
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return 0
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}
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