mathjs/docs/reference/functions/dot.md

Math.js is an extensive math library for JavaScript and Node.js. It features a flexible expression parser and offers an integrated solution to work with numbers, big numbers, complex numbers, units, and matrices.

# Function dot

Calculate the dot product of two vectors. The dot product of
`A = [a1, a2, a3, ..., an]` and `B = [b1, b2, b3, ..., bn]` is defined as:

   dot(A, B) = a1 * b1 + a2 * b2 + a3 * b3 + ... + an * bn


## Syntax

```js
math.dot(x, y)
```

### Parameters

Parameter | Type | Description
--------- | ---- | -----------
`x` | Array | Matrix | First vector
`y` | Array | Matrix | Second vector

### Returns

Type | Description
---- | -----------
Number | Returns the dot product of `x` and `y`


## Examples

```js
math.dot([2, 4, 1], [2, 2, 3]);       // returns Number 15
math.multiply([2, 4, 1], [2, 2, 3]);  // returns Number 15
```


## See also

[multiply](multiply.md),
[cross](cross.md)


<!-- Note: This file is automatically generated from source code comments. Changes made in this file will be overridden. -->