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package mathx
import "math"
// AbsInt returns the absolute value of i.
func AbsInt(i int) int {
if i < 0 {
return -i
}
return i
}
// Round returns x rounded to the given unit.
// Tip: x is "arbitrary", maybe greater than 1.
// For example:
// Round(0.363636, 0.001) // 0.364
// Round(0.363636, 0.01) // 0.36
// Round(0.363636, 0.1) // 0.4
// Round(0.363636, 0.05) // 0.35
// Round(3.2, 1) // 3
// Round(32, 5) // 30
// Round(33, 5) // 35
// Round(32, 10) // 30
//
// For details, see https://stackoverflow.com/a/39544897/1705598
func Round(x, unit float64) float64 {
return math.Round(x/unit) * unit
}
// Near reports if 2 float64 numbers are "near" to each other.
// The caller is responsible to provide a sensible epsilon.
//
// "near" is defined as the following:
// near := math.Abs(a - b) < eps
//
// Corner cases:
// 1. if a==b, result is true (eps will not be checked, may be NaN)
// 2. Inf is near to Inf (even if eps=NaN; consequence of 1.)
// 3. -Inf is near to -Inf (even if eps=NaN; consequence of 1.)
// 4. NaN is not near to anything (not even to NaN)
// 5. eps=Inf results in true (unless any of a or b is NaN)
func Near(a, b, eps float64) bool {
// Quick check, also handles infinities:
if a == b {
return true
}
return math.Abs(a-b) < eps
}
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