56 lines
1.1 KiB
Markdown
56 lines
1.1 KiB
Markdown
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<!-- Note: This file is automatically generated from source code comments. Changes made in this file will be overridden. -->
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# Function index
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Create an index. An Index can store ranges having start, step, and end
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for multiple dimensions.
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Matrix.get, Matrix.set, and math.subset accept an Index as input.
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## Syntax
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```js
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math.index(range1, range2, ...)
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```
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### Where
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- A number
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- A string for getting/setting an object property
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- An instance of `Range`
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- A one-dimensional Array or a Matrix with numbers
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### Parameters
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Parameter | Type | Description
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--------- | ---- | -----------
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`ranges` | ...* | Zero or more ranges or numbers.
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### Returns
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Type | Description
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---- | -----------
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Index | Returns the created index
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## Examples
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```js
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const b = [1, 2, 3, 4, 5]
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math.subset(b, math.index([1, 2, 3])) // returns [2, 3, 4]
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const a = math.matrix([[1, 2], [3, 4]])
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a.subset(math.index(0, 1)) // returns 2
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```
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## See also
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[bignumber](bignumber.md),
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[boolean](boolean.md),
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[complex](complex.md),
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[matrix](matrix.md),
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[number](number.md),
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[string](string.md),
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[unit](unit.md)
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