From: Keith Packard <keithp@keithp.com>
Date: Thu, 12 Oct 2017 07:30:23 +0000 (-0700)
Subject: altoslib: Fix time series filter window computation
X-Git-Tag: 1.8.3~1^2~70
X-Git-Url: https://git.gag.com/?p=fw%2Faltos;a=commitdiff_plain;h=77d1aee917306ad59492c4c8352fe2125b430d0c

altoslib: Fix time series filter window computation

Small floating point rounding errors could lead to NaNs.

Signed-off-by: Keith Packard <keithp@keithp.com>
---

diff --git a/altoslib/AltosTimeSeries.java b/altoslib/AltosTimeSeries.java
index 7208c176..c6a780a3 100644
--- a/altoslib/AltosTimeSeries.java
+++ b/altoslib/AltosTimeSeries.java
@@ -294,7 +294,7 @@ public class AltosTimeSeries implements Iterable<AltosTimeValue>, Comparable<Alt
 		double alpha = m / 2;
 		double t = (n - alpha) / alpha;
 
-		if (t > 1)
+		if (t > 1 || t < -1)
 			t = 1;
 		double k = i0 (beta * Math.sqrt (1 - t*t)) / i0(beta);
 		return k;