2019-06-05 21:08:38 +10:00

64 lines
1.2 KiB
Go

package asciigraph
import "math"
func minMaxFloat64Slice(v []float64) (min, max float64) {
min = math.Inf(1)
max = math.Inf(-1)
if len(v) == 0 {
panic("Empty slice")
}
for _, e := range v {
if e < min {
min = e
}
if e > max {
max = e
}
}
return
}
func round(input float64) float64 {
if math.IsNaN(input) {
return math.NaN()
}
sign := 1.0
if input < 0 {
sign = -1
input *= -1
}
_, decimal := math.Modf(input)
var rounded float64
if decimal >= 0.5 {
rounded = math.Ceil(input)
} else {
rounded = math.Floor(input)
}
return rounded * sign
}
func linearInterpolate(before, after, atPoint float64) float64 {
return before + (after-before)*atPoint
}
func interpolateArray(data []float64, fitCount int) []float64 {
var interpolatedData []float64
springFactor := float64(len(data)-1) / float64(fitCount-1)
interpolatedData = append(interpolatedData, data[0])
for i := 1; i < fitCount-1; i++ {
spring := float64(i) * springFactor
before := math.Floor(spring)
after := math.Ceil(spring)
atPoint := spring - before
interpolatedData = append(interpolatedData, linearInterpolate(data[int(before)], data[int(after)], atPoint))
}
interpolatedData = append(interpolatedData, data[len(data)-1])
return interpolatedData
}