succd: implement threshold outputs, rework processing

succbone/succd/scientific.go

@@ -0,0 +1,33 @@
+package main
+
+import (
+	"fmt"
+	"strconv"
+)
+
+type ScientificNotationValue float64
+
+func (s *ScientificNotationValue) UnmarshalText(text []byte) error {
+	f, err := strconv.ParseFloat(string(text), 64)
+	if err != nil {
+		return err
+	}
+	*s = ScientificNotationValue(f)
+	return nil
+}
+
+func (s *ScientificNotationValue) MarshalText() ([]byte, error) {
+	v := float64(*s)
+	exp := 0
+	for v < 1 {
+		v *= 10
+		exp -= 1
+	}
+	for v >= 10 {
+		v /= 10
+		exp += 1
+	}
+	res := fmt.Sprintf("%.3f", v)
+	res += fmt.Sprintf("e%d", exp)
+	return []byte(res), nil
+}