mult and div by point

mapbox · Sep 27, 2016 · efb6368 · efb6368
1 parent f52f37a
commit efb6368
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Showing 3 changed files with 89 additions and 18 deletions.
diff --git a/README.md b/README.md
@@ -69,21 +69,53 @@ yielding a new point.
 
 ### `mult(k)`
 
-Multiply this point's x & y coordinates with from point,
+Multiply this point's x & y coordinates by fractor,
+yielding a new point.
+
+### Parameters
+
+| parameter | type   | description    |
+| --------- | ------ | -------------- |
+| `k`       | Number | fractor        |
+
+
+
+**Returns** `Point`, output point
+
+
+### `div(k)`
+
+Divide this point's x & y coordinates by divider,
+yielding a new point.
+
+### Parameters
+
+| parameter | type   | description    |
+| --------- | ------ | -------------- |
+| `k`       | Number | divider        |
+
+
+
+**Returns** `Point`, output point
+
+
+### `multByPoint(p)`
+
+Multiply this point's x & y coordinates by point,
 yielding a new point.
 
 ### Parameters
 
 | parameter | type  | description     |
 | --------- | ----- | --------------- |
-| `k`       | Point | the other point |
+| `p`       | Point | the other point |
 
 
 
 **Returns** `Point`, output point
 
 
-### `div(k)`
+### `divByPoint(p)`
 
 Divide this point's x & y coordinates with from point,
 yielding a new point.
@@ -92,7 +124,7 @@ yielding a new point.
 
 | parameter | type  | description     |
 | --------- | ----- | --------------- |
-| `k`       | Point | the other point |
+| `p`       | Point | the other point |
 
 
 

diff --git a/index.js b/index.js
@@ -45,15 +45,31 @@ Point.prototype = {
     sub:     function(p) { return this.clone()._sub(p); },
 
     /**
-     * Multiply this point's x & y coordinates with from point,
+     * Multiply this point's x & y coordinates by point,
+     * yielding a new point.
+     * @param {Point} p the other point
+     * @return {Point} output point
+     */
+    multByPoint:    function(p) { return this.clone()._multByPoint(p); },
+
+    /**
+     * Divide this point's x & y coordinates by point,
+     * yielding a new point.
+     * @param {Point} p the other point
+     * @return {Point} output point
+     */
+    divByPoint:     function(p) { return this.clone()._divByPoint(p); },
+
+    /**
+     * Multiply this point's x & y coordinates by point,
      * yielding a new point.
      * @param {Point} k the other point
      * @return {Point} output point
      */
     mult:    function(k) { return this.clone()._mult(k); },
 
     /**
-     * Divide this point's x & y coordinates with from point,
+     * Divide this point's x & y coordinates by point,
      * yielding a new point.
      * @param {Point} k the other point
      * @return {Point} output point
@@ -212,20 +228,31 @@ Point.prototype = {
     },
 
     _mult: function(k) {
-        this.x *= k.x;
-        this.y *= k.y;
+        this.x *= k;
+        this.y *= k;
         return this;
     },
 
     _div: function(k) {
-        this.x /= k.x;
-        this.y /= k.y;
+        this.x /= k;
+        this.y /= k;
+        return this;
+    },
+
+    _multByPoint: function(p) {
+        this.x *= p.x;
+        this.y *= p.y;
+        return this;
+    },
+
+    _divByPoint: function(p) {
+        this.x /= p.x;
+        this.y /= p.y;
         return this;
     },
 
     _unit: function() {
-        var m = this.mag();
-        this._div(new Point(m,m));
+        this._div(this.mag());
         return this;
     },
 

diff --git a/test.js b/test.js
@@ -37,15 +37,27 @@ test('Point', function(t) {
             t.end();
         });
         t.test('#mult', function(t) {
-            t.equals((new Point(0, 0).mult(new Point(5,5))).equals(new Point(0, 0)), true);
-            t.equals((new Point(0, 1).mult(new Point(5,5))).equals(new Point(0, 5)), true);
-            t.equals((new Point(1, 1).mult(new Point(5,5))).equals(new Point(5, 5)), true);
+            t.equals((new Point(0, 0).mult(5)).equals(new Point(0, 0)), true);
+            t.equals((new Point(0, 1).mult(5)).equals(new Point(0, 5)), true);
+            t.equals((new Point(1, 1).mult(5)).equals(new Point(5, 5)), true);
             t.end();
         });
         t.test('#div', function(t) {
-            t.equals((new Point(0, 0).div(new Point(5,5))).equals(new Point(0, 0)), true);
-            t.equals((new Point(0, 1).div(new Point(5,5))).equals(new Point(0, 1/5)), true);
-            t.equals((new Point(1, 1).div(new Point(5,5))).equals(new Point(1/5, 1/5)), true);
+            t.equals((new Point(0, 0).div(5)).equals(new Point(0, 0)), true);
+            t.equals((new Point(0, 1).div(5)).equals(new Point(0, 1/5)), true);
+            t.equals((new Point(1, 1).div(5)).equals(new Point(1/5, 1/5)), true);
+            t.end();
+        });
+        t.test('#multByPoint', function(t) {
+            t.equals((new Point(0, 0).multByPoint(new Point(5,5))).equals(new Point(0, 0)), true);
+            t.equals((new Point(0, 1).multByPoint(new Point(5,5))).equals(new Point(0, 5)), true);
+            t.equals((new Point(1, 1).multByPoint(new Point(4,5))).equals(new Point(4, 5)), true);
+            t.end();
+        });
+        t.test('#divByPoint', function(t) {
+            t.equals((new Point(0, 0).divByPoint(new Point(5,5))).equals(new Point(0, 0)), true);
+            t.equals((new Point(0, 1).divByPoint(new Point(5,5))).equals(new Point(0, 1/5)), true);
+            t.equals((new Point(1, 1).divByPoint(new Point(4,5))).equals(new Point(1/4, 1/5)), true);
             t.end();
         });
         t.test('#rotate', function(t) {