linear.go
1.11 KB
package influxql
// linearFloat computes the the slope of the line between the points (previousTime, previousValue) and (nextTime, nextValue)
// and returns the value of the point on the line with time windowTime
// y = mx + b
func linearFloat(windowTime, previousTime, nextTime int64, previousValue, nextValue float64) float64 {
m := (nextValue - previousValue) / float64(nextTime-previousTime) // the slope of the line
x := float64(windowTime - previousTime) // how far into the interval we are
b := previousValue
return m*x + b
}
// linearInteger computes the the slope of the line between the points (previousTime, previousValue) and (nextTime, nextValue)
// and returns the value of the point on the line with time windowTime
// y = mx + b
func linearInteger(windowTime, previousTime, nextTime int64, previousValue, nextValue int64) int64 {
m := float64(nextValue-previousValue) / float64(nextTime-previousTime) // the slope of the line
x := float64(windowTime - previousTime) // how far into the interval we are
b := float64(previousValue)
return int64(m*x + b)
}