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# Golden Ratio (φ)

> [Golden ratio][phi].

<section class="intro">

The [golden ratio][phi] can be defined algebraically as

<!-- <equation class="equation" label="eq:golden_ratio" align="center" raw="\phi = \frac{1 + \sqrt{5}}{2}" alt="Golden ratio"> -->

<div class="equation" align="center" data-raw-text="\phi = \frac{1 + \sqrt{5}}{2}" data-equation="eq:golden_ratio">
    <img src="https://cdn.jsdelivr.net/gh/stdlib-js/stdlib@5d87cc7cb2c58aeb732872f89562d2c89571cc8a/lib/node_modules/@stdlib/constants/float64/phi/docs/img/equation_golden_ratio.svg" alt="Golden ratio">
    <br>
</div>

<!-- </equation> -->

</section>

<!-- /.intro -->

<section class="usage">

## Usage

```javascript
var PHI = require( '@stdlib/constants/float64/phi' );
```

#### PHI

The [golden ratio][phi-value].

```javascript
var bool = ( PHI === 1.618033988749895 );
// returns true
```

</section>

<!-- /.usage -->

<section class="examples">

## Examples

<!-- TODO: better example using Fibonacci(?) -->

<!-- eslint no-undef: "error" -->

```javascript
var PHI = require( '@stdlib/constants/float64/phi' );

console.log( PHI );
// => 1.618033988749895
```

</section>

<!-- /.examples -->

<section class="links">

[phi]: http://en.wikipedia.org/wiki/Golden_ratio

[phi-value]: http://oeis.org/A001622

</section>

<!-- /.links -->