From 1f698aa6ee526471416408b24bf64f258175c7f4 Mon Sep 17 00:00:00 2001
From: Tim Edwards <tim@opencircuitdesign.com>
Date: Wed, 17 Feb 2021 21:15:54 -0500
Subject: [PATCH] Merged pull request #53 from Dan Moore.

---
 extract/ExtCouple.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/extract/ExtCouple.c b/extract/ExtCouple.c
index 64aa56d7..dea2d9c2 100644
--- a/extract/ExtCouple.c
+++ b/extract/ExtCouple.c
@@ -897,6 +897,9 @@ extSideOverlap(tp, esws)
 	    subcap = (ExtCurStyle->exts_perimCap[ta][outtype] *
 			MIN(areaAccountedFor, length));
 	    rbp->nreg_cap -= subcap;
+	    /* Ignore residual error at ~zero zeptoFarads.  Probably	*/
+	    /* there should be better handling of round-off here.	*/
+	    if ((rbp->nreg_cap > -0.001) && (rbp->nreg_cap < 0.001)) rbp->nreg_cap = 0;
 	    if (CAP_DEBUG)
 		extNregAdjustCap(rbp, -subcap, "obsolete_perimcap");
 	} else if (CAP_DEBUG)