57 lines
1.2 KiB
Markdown
57 lines
1.2 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 apply
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Apply a function that maps an array to a scalar
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along a given axis of a matrix or array.
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Returns a new matrix or array with one less dimension than the input.
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## Syntax
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```js
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math.apply(A, dim, callback)
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```
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### Where
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- `dim: number` is a zero-based dimension over which to concatenate the matrices.
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### Parameters
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Parameter | Type | Description
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--------- | ---- | -----------
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`array` | Array | Matrix | The input Matrix
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`dim` | number | The dimension along which the callback is applied
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`callback` | Function | The callback function that is applied. This Function should take an array or 1-d matrix as an input and return a number.
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### Returns
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Type | Description
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---- | -----------
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Array | Matrix | res The residual matrix with the function applied over some dimension.
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### Throws
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Type | Description
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---- | -----------
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## Examples
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```js
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const A = [[1, 2], [3, 4]]
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const sum = math.sum
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math.apply(A, 0, sum) // returns [4, 6]
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math.apply(A, 1, sum) // returns [3, 7]
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```
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## See also
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[map](map.md),
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[filter](filter.md),
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[forEach](forEach.md)
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