Merge pull request #39 from jamiealquiza/jamie/scale-fix

scale func updated to handle all equal input values
jamiealquiza · May 2, 2018 · 648c1d0 · 648c1d0
2 parents e886387 + 4223a84
commit 648c1d0
Showing 1 changed file with 8 additions and 1 deletion.
diff --git a/tachymeter.go b/tachymeter.go
@@ -294,5 +294,12 @@ func (h *Histogram) String(s int) string {
 // Scale scales the input x with the input-min a0,
 // input-max a1, output-min b0, and output-max b1.
 func scale(x, a0, a1, b0, b1 float64) float64 {
-	return (x-a0)/(a1-a0)*(b1-b0) + b0
+	a, b := x-a0, a1-a0
+	var c float64
+	if a == 0 {
+		c = 0
+	} else {
+		c = a / b
+	}
+	return c*(b1-b0) + b0
 }