73 lines
1016 B
Markdown
73 lines
1016 B
Markdown
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# sparse-array
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[](https://travis-ci.org/pgte/js-sparse-array)
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Sparse array implementation in JS with no dependencies
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## Install
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```bash
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$ npm install sparse-array --save
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```
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## Use
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### Create:
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```js
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const SparseArray = require('sparse-array')
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const arr = new SparseArray()
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```
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### Set, get and unset:
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```js
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const index = 0
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arr.set(index, 'value')
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arr.get(index) // 'value'
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arr.unset(index)
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arr.get(index) // undefined
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```
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### Iterate:
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```js
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arr.forEach((elem, index) => {
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console.log('elem: %j at %d', elem, index)
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})
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const mapped = arr.map((elem, index) => {
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return elem + 1
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})
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const result = arr.reduce((acc, elem, index) => {
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return acc + Number(elem)
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}, 0)
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```
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### Find:
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```js
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const firstEven = arr.find((elem) => (elem % 2) === 0)
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```
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### Internal representation:
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#### Bit field:
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```js
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const bitField = arr.bitField()
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```
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#### Compact array:
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```js
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const compacted = arr.compactArray()
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```
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## License
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ISC
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