# polygon-eq

> compare if two polygons are equal. multipolygons and holes supported

Latest version **1.0.3** (published 2021-12-23) · bsd license · 0 weekly downloads

## Install

```sh
npm install polygon-eq
pnpm add polygon-eq
yarn add polygon-eq
bun add polygon-eq
```

## Health

**Score 15/100 (F)** — status: abandoned.

Positive: no vulnerabilities.

Warnings: low downloads; no types; no esm support.

Negative: abandoned; low maintenance score.

## Facts

| | |
|---|---|
| Version | 1.0.3 |
| Published | 2021-12-23 |
| First published | 2021-12-21 |
| Weekly downloads | 0 |
| License | bsd |
| TypeScript types | none |
| Module format | CommonJS |
| Dependencies | 0 |
| Unpacked size | 13.1 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| Maintainers | substack |

## Links

- npm: https://www.npmjs.com/package/polygon-eq
- npm.io page: https://npm.io/package/polygon-eq

## Recent versions

- 1.0.3 (latest) — 2021-12-23
- 1.0.2 — 2021-12-22
- 1.0.1 — 2021-12-21
- 1.0.0 — 2021-12-21

## README

# polygon-eq

compare if two polygons are equal. multipolygons and holes supported.

The comparison ignores whether or not there is a duplicate first and last node.

Rings with reversed orders (clockwise or counter-clockwise) are considered equal if their points are
equal. Holes and sub-polygons can appear in any order.

The data for polygons is pretty much geojson coordinates field for polygons types but more lenient.

# example

single polygons:

``` js
var eq = require('polygon-eq')
var A = [[6.25,6],[10,12],[10,4],[7.5,4],[10,0],[0,0],[5,8]]
var B = [[10,0],[7.5,4],[10,4],[10,12],[6.25,6],[5,8],[0,0],[10,0]]
var C = [[6.25,6],[10,12],[7.5,4],[10,4],[10,0],[0,0],[5,8]]
console.log(eq(A,B)) // true
console.log(eq(A,C)) // false
```

single polygons with holes:

``` js
var eq = require('polygon-eq')
var A = [
  [[5,8],[6.25,6],[10,12],[15,-2],[7,-2],[8,0],[0,0],[5,8]],
  [[8.889,1.778],[10,4],[7.5,4],[8.889,1.778]]
]
var B = [
  [[6.25,6],[5,8],[0,0],[8,0],[7,-2],[15,-2],[10,12]],
  [[7.5,4],[8.889,1.778],[10,4],[7.5,4]]
]
var C = [
  [[6.25,6],[5,8],[0,0],[8,0],[7,-2],[15,-2],[10,12]],
  [[7.5,4],[8.889,1.778],[10,4.1]],
]
console.log(eq(A,B)) // true
console.log(eq(A,C)) // false
```

multipolygons, some polygons with holes, some without:

``` js
var eq = require('polygon-eq')
var A = [
  [
    [[6.25,6],[10,12],[15,-2],[7,-2],[8,0],[0,0],[5,8]],
    [[8.889,1.778],[10,4],[7.5,4],[8.889,1.778]],
  ],
  [[[-4,+4],[-4,+7],[-2,+5],[-4,+4]]],
]
var B = [
  [[[-4,+7],[-4,+4],[-2,+5],[-4,+7]]],
  [
    [[6.25,6],[5,8],[0,0],[8,0],[7,-2],[15,-2],[10,12],[6.25,6]],
    [[7.5,4],[8.889,1.778],[10,4]],
  ],
]
console.log(eq(A,B)) // true
```

# api

``` js
var eq = require('polygon-eq')
```

## eq(A, B, epsilon=1e-8)

Return a boolean, whether or not polygons `A` and `B` are equal.

Polygons work like the geojson coordinates field for polygon and multipolygon types but can also be
depth 2 and do not require that the first point and last point are equal in a ring.

* depth=2 - single polygon: `[[x0,y0],[x1,y1],...]`
* depth=3 - single polygon with holes: `[[[x0,y0],[x1,y1],...],hole0,hole1...]`
* depth=4 - multiple polygons, each with holes: `[polygon0,polygon1,...]`

Each hole is formatted like a single polygon: `[[x0,y0],[x1,y1],...]`.

# install

npm install polygon-eq

# license

bsd

---
_Source: https://npm.io/package/polygon-eq · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._