From e700df5059693a5e237cbf44be54e8d40b2ad1db Mon Sep 17 00:00:00 2001
From: Pitchaya Boonsarngsuk <2285135b@student.gla.ac.uk>
Date: Wed, 31 Jan 2018 15:59:00 +0000
Subject: [PATCH] Fix bug divide by 0 by adding jiggle

---
 src/interpolation/interpCommon.js | 10 +++++-----
 src/link.js                       |  2 +-
 src/neighbourSamplingDistance.js  |  2 +-
 3 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/interpolation/interpCommon.js b/src/interpolation/interpCommon.js
index bf8234b..009a4cb 100644
--- a/src/interpolation/interpCommon.js
+++ b/src/interpolation/interpCommon.js
@@ -1,4 +1,5 @@
 import {pointOnCircle, sumDistError} from "./helpers";
+import jiggle from "../jiggle";
 
 export function placeNearToNearestNeighbour(node, nearNeighbour, radius, sampleSubset, realDistances) {
   let
@@ -43,8 +44,6 @@ export function placeNearToNearestNeighbour(node, nearNeighbour, radius, sampleS
                                return sumDistError(pointOnCircle(nearNeighbour.x, nearNeighbour.y, angle, radius), sampleSubset, realDistances);
                              });
   let newPoint = pointOnCircle(nearNeighbour.x, nearNeighbour.y, angle, radius);
-
-  // console.log(newPoint);
   node.x = newPoint.x;
   node.y = newPoint.y;
 
@@ -65,9 +64,10 @@ function sumForcesToSample(node, samples, sampleCache) {
     var sample = samples[i];
     if(sample === node) continue;
 
-    let x = node.x - sample.x,
-        y = node.y - sample.y,
-        l = Math.sqrt(x * x + y * y);
+    // jiggle so l won't be zero and divide by zero error after this
+    x = node.x - sample.x || jiggle();
+    y = node.y - sample.y || jiggle();
+    l = Math.sqrt(x * x + y * y);
 
     l = (l - sampleCache[i]) / l;
     x *= l, y *= l;
diff --git a/src/link.js b/src/link.js
index f04012b..2316ea1 100644
--- a/src/link.js
+++ b/src/link.js
@@ -22,7 +22,7 @@ export default function(links) {
     for (var k = 0, n = nodes.length, source, target, i, j, x, y, l; k < iterations; ++k) {
       // For each link
       for (i = 1; i < n; i++) for (j = 0; j < i; j++) {
-        // jiggle so it wont divide / multiply by zero after this
+        // jiggle so l won't be zero and divide by zero error after this
         source = nodes[i];
         target = nodes[j];
         x = target.x + target.vx - source.x - source.vx || jiggle();
diff --git a/src/neighbourSamplingDistance.js b/src/neighbourSamplingDistance.js
index 480153a..890fa5f 100644
--- a/src/neighbourSamplingDistance.js
+++ b/src/neighbourSamplingDistance.js
@@ -79,7 +79,7 @@ export default function () {
    */
   function setVelocity(source, target, dist, alpha) {
     let x, y, l;
-    // jiggle so it wont divide / multiply by zero after this
+    // jiggle so l won't be zero and divide by zero error after this
     x = target.x + target.vx - source.x - source.vx || jiggle();
     y = target.y + target.vy - source.y - source.vy || jiggle();
     l = Math.sqrt(x * x + y * y);