forked from golang/hotime
39 lines
910 B
Go
39 lines
910 B
Go
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package stats
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import "math"
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// Round a float to a specific decimal place or precision
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func Round(input float64, places int) (rounded float64, err error) {
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// If the float is not a number
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if math.IsNaN(input) {
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return math.NaN(), NaNErr
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}
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// Find out the actual sign and correct the input for later
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sign := 1.0
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if input < 0 {
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sign = -1
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input *= -1
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}
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// Use the places arg to get the amount of precision wanted
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precision := math.Pow(10, float64(places))
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// Find the decimal place we are looking to round
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digit := input * precision
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// Get the actual decimal number as a fraction to be compared
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_, decimal := math.Modf(digit)
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// If the decimal is less than .5 we round down otherwise up
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if decimal >= 0.5 {
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rounded = math.Ceil(digit)
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} else {
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rounded = math.Floor(digit)
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}
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// Finally we do the math to actually create a rounded number
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return rounded / precision * sign, nil
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}
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