diff --git a/lib/charts/bubble.js b/lib/charts/bubble.js
index 7a97ab4..0bc0720 100644
--- a/lib/charts/bubble.js
+++ b/lib/charts/bubble.js
@@ -68,7 +68,7 @@
     });
 
     /**
-     * create a backCanvas for the visualization
+     * Creates a backCanvas for the visualization
      */
     Bubble.prototype.createCanvas = function () {
         var conf = this.defaults;
@@ -90,7 +90,7 @@
     };
 
     /**
-     * choose bubble graph setted visualization dimens orderly
+     * Chooses bubble graph setted visualization dimens orderly
      */
     Bubble.prototype.chooseDimensions = function (dimen) {
         var conf = this.defaults;
@@ -130,10 +130,10 @@
         conf.dimensions = source[0];
 
         this.source = [];
-        for(var i = 1, l = source.length; i < l; i++){
+        for (var i = 1, l = source.length; i < l; i++){
             var dot = {},
                 dimen = conf.allDimensions;
-            for(var j=0, ll=dimen.length; j < ll; j++){
+            for (var j=0, ll=dimen.length; j < ll; j++){
                 dot[dimen[j]] = source[i][j];
             }
             this.source.push(dot);
@@ -141,14 +141,11 @@
 
         // judge dimesions type auto
         conf.dimensionType = {};
-        function isNumber(n) {
-            return !isNaN(parseFloat(n)) && isFinite(n);
-        }
-        for(var i = 0, l = conf.allDimensions.length; i < l; i++){
+        for (var i = 0, l = conf.allDimensions.length; i < l; i++){
             var type = "quantitative";
-            for(var j = 1, ll = source.length; j < ll; j++){
+            for (var j = 1, ll = source.length; j < ll; j++){
                 var d = source[j][i];
-                if(d && (! isNumber(d))){
+                if(d && (!DataV.isNumeric(d))){
                     type = "ordinal";
                     break;
                 }
@@ -157,12 +154,12 @@
         }
 
         // set default dimensionDomain
-        for(var i = 0, l = conf.allDimensions.length; i < l; i++){
+        for (var i = 0, l = conf.allDimensions.length; i < l; i++){
             var dimen = conf.allDimensions[i];
-            if(conf.dimensionType[dimen] === "quantitative"){
+            if (conf.dimensionType[dimen] === "quantitative") {
                 conf.dimensionDomain[dimen] = d3.extent(this.source,
-                     function(p){return Math.abs(p[dimen])});
-            }else{
+                     function (p) {return Math.abs(p[dimen]);});
+            } else {
                 conf.dimensionDomain[dimen] =
                     this.source.map(function(p){return p[dimen]});
             }
@@ -483,6 +480,7 @@
         }
 
         var floatTag = this.floatTag;
+        var that = this;
         var tip = '<b>' + that.keyDimen + ':{key}</b><br/><b>' +
             that.xDimen + ':{xDimen}</b><br/><b>' +
             that.yDimen + ':{yDimen}</b><br/><b>' +
@@ -762,7 +760,6 @@
                 value += 0.25;
             } else {
                 clearInterval(that.interval);
-                that.interval = 0;
             }
         }, 250);
     };
@@ -791,7 +788,6 @@
      */
     Bubble.prototype.clearAnimation = function () {
         clearInterval(this.interval);
-        this.interval = 0;
         this.backCanvas.clear();
         this.foreCanvas.clear();
     };
@@ -801,7 +797,6 @@
      */
     Bubble.prototype.pause = function () {
         clearInterval(this.interval);
-        this.interval = 0;
     };
 
     /**
diff --git a/test/lib.chord.js b/test/lib.chord.js
index e2f1a34..c68b4a2 100644
--- a/test/lib.chord.js
+++ b/test/lib.chord.js
@@ -7,19 +7,19 @@ test("prototype.createCanvas", function () {
     equal(fdnet.defaults.innerRadius, 328, "innerRadius should be 328 by default");
 
     fdnet.createCanvas();
-  
+
     equal(typeof fdnet.canvas, "object", "canvas should be an object");
 });
 
 test("prototype.setSource", function () {
-    var source=[
+    var source = [
         ["A", "B", "C", "D"],
         [11975, 5871, 8916, 2868],
         [1951, 10048, 2060, 6171],
         [8010, 16145, 8090, 8045],
         [1013, 990, 940, 6907]
     ];
-    
+
     fdnet.setSource(source);
 
     equal(fdnet.matrix.length, 4, "There should be 4 groups.");
@@ -29,7 +29,7 @@ test("prototype.setSource", function () {
 });
 
 test("prototype.render", function () {
-    var source=[
+    var source = [
         ["A", "B", "C", "D"],
         [11975, 5871, 8916, 2868],
         [1951, 10048, 2060, 6171],