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readme.md

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+# fractions-math
+
+<div align="center">
+  <a href="https://npmjs.org/package/fractions-math">
+    <img src="https://badgen.net/npm/v/fractions-math" alt="version" />
+  </a>
+  <a href="https://github.com/vladkens/fractions-math/actions">
+    <img src="https://github.com/vladkens/fractions-math/workflows/test/badge.svg" alt="test status" />
+  </a>
+  <a href="https://packagephobia.now.sh/result?p=fractions-math">
+    <img src="https://badgen.net/packagephobia/publish/fractions-math" alt="size" />
+  </a>
+  <a href="https://npmjs.org/package/fractions-math">
+    <img src="https://badgen.net/npm/dm/fractions-math" alt="downloads" />
+  </a>
+  <a href="https://github.com/vladkens/fractions-math/blob/main/LICENSE">
+    <img src="https://badgen.net/github/license/vladkens/fractions-math" alt="license" />
+  </a>
+</div>
+
+Implementing [`fractions`](https://docs.python.org/3/library/fractions.html) module from The Python Standard Library on TypeScript.
+
+## Install
+
+```sh
+yarn add fractions-math
+```
+
+## Usage
+
+```typescript
+import { Fraction, fraq } from "fractions-math"
+
+const f1 = new Fraction(1, 2)
+const f2 = fraq(1.5)
+const f3 = f1.add(f2).toString() // -> "2" (0.5 + 1.5)
+const f4 = f3.mul(f2).toString() // -> "3" (2 * 1.5)
+const f5 = f4.div(f1).toString() // -> "6" (3 / 0.5)
+```
+
+## API
+
+### `fraq(...args) / Fraction.make(...args)`
+
+Helper function to create fraction from various inputs.
+
+```typescript
+fraq(1, 2).toPair() // -> [1, 2]
+fraq(2).toPair() // -> [2, 1]
+fraq([2, 1]).toPair() // -> [2, 1]
+fraq(0.5).toPair() // -> [1, 2]
+```
+
+### `new Fraction(n: number, d = 1, reduce = true)`
+
+Creates a fraction taking two numbers – numenator and denominator. Denominator has default value `1`. By default, the fraction is reduced to the minimum form.
+
+```typescript
+new Fraction(1, 2).toPair() // -> [1, 2]
+new Fraction(2).toPair() // -> [2, 1]
+new Fraction(5, 10).toPair() // -> [1, 2]
+new Fraction(5, 10, false).toPair() // -> [5, 10]
+```
+
+### `.toString()`
+
+```typescript
+fraq(1, 2).toString() // -> "1/2"
+fraq(3, 3).toString() // -> "3"
+fraq(-1).toString() // -> "-1"
+fraq(1, -2).toString() // -> "-1/2"
+```
+
+### `.toNumber()`
+
+```typescript
+fraq(1, 2).toString() // -> 0.5
+```
+
+### `.limit(max: number = 10_000)`
+
+Finds the closest Fraction that has denominator at most `max`.
+
+```typescript
+fraq(Math.PI).limit(1000).toString() // -> "355/113"
+fraq(1.1).limit().toString() // -> "11/10"
+```
+
+### `.add(b: Fraction | number | [number, number])`
+
+```typescript
+fraq(1, 2).add([-1, 2]).toString() // -> "0"
+fraq(1, 2).add(1).toString() // -> "3/2"
+```
+
+### `.sub(b: Fraction | number | [number, number])`
+
+```typescript
+fraq(1, 2).sub([1, 2]).toString() // -> "0"
+fraq(1, 2).sub(1).toString() // -> "-1/2"
+```
+
+### `.mul(b: Fraction | number | [number, number])`
+
+```typescript
+fraq(1, 2).mul([1, 2]).toString() // -> "1/4"
+fraq(1, 2).mul(1.5).toString() // -> "3/4"
+```
+
+### `.div(b: Fraction | number | [number, number])`
+
+```typescript
+fraq(1, 2).div([1, 2]).toString() // -> "1"
+fraq(1, 2).div(1.5).toString() // -> "1/3"
+fraq(1, 2).div(0).toString() // throws Error
+```
+
+### `.eq(b: Fraction | number | [number, number])`
+
+```typescript
+fraq(1, 2).eq(0.5) // -> true
+fraq(1, 2).eq([1, 3]) // -> false
+```
+
+### `.lt(b: Fraction | number | [number, number]) -> boolean`
+
+### `.lte(b: Fraction | number | [number, number]) -> boolean`
+
+### `.gt(b: Fraction | number | [number, number]) -> boolean`
+
+### `.gte(b: Fraction | number | [number, number]) -> boolean`