76 lines
1.5 KiB
Markdown
76 lines
1.5 KiB
Markdown
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---
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id: 5a23c84252665b21eecc7e1e
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title: Dot product
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challengeType: 5
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forumTopicId: 302251
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dashedName: dot-product
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---
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# --description--
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Create a function, to compute the **[dot product](https://en.wikipedia.org/wiki/Dot product)**, also known as the **scalar product** of two vectors.
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# --hints--
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`dotProduct` should be a function.
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```js
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assert(typeof dotProduct == 'function');
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```
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`dotProduct([1, 3, -5], [4, -2, -1])` should return a number.
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```js
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assert(typeof dotProduct([1, 3, -5], [4, -2, -1]) == 'number');
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```
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`dotProduct([1, 3, -5], [4, -2, -1])` should return `3`.
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```js
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assert.equal(dotProduct([1, 3, -5], [4, -2, -1]), 3);
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```
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`dotProduct([1, 2, 3, 4, 5], [6, 7, 8, 9, 10])` should return `130`.
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```js
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assert.equal(dotProduct([1, 2, 3, 4, 5], [6, 7, 8, 9, 10]), 130);
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```
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`dotProduct([5, 4, 3, 2], [7, 8, 9, 6])` should return `106`.
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```js
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assert.equal(dotProduct([5, 4, 3, 2], [7, 8, 9, 6]), 106);
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```
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`dotProduct([-5, 4, -3, 2], [-7, -8, 9, -6])` should return `-36`.
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```js
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assert.equal(dotProduct([-5, 4, -3, 2], [-7, -8, 9, -6]), -36);
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```
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`dotProduct([17, 27, 34, 43, 15], [62, 73, 48, 95, 110])` should return `10392`.
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```js
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assert.equal(dotProduct([17, 27, 34, 43, 15], [62, 73, 48, 95, 110]), 10392);
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```
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# --seed--
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## --seed-contents--
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```js
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function dotProduct(ary1, ary2) {
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}
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```
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# --solutions--
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```js
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function dotProduct(ary1, ary2) {
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var dotprod = 0;
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for (var i = 0; i < ary1.length; i++) dotprod += ary1[i] * ary2[i];
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return dotprod;
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}
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```
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