feat: add blas/ext/index-of

[headlessNode]

Progresses #2656.

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This pull request:

• add blas/ext/index-of

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This pull request:

• progresses [RFC]: achieve ndarray API parity with built-in JavaScript arrays  #2656

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Coverage Report

Package	Statements	Branches	Functions	Lines
blas/ext/index-of	$\color{green}582/582$ $\color{green}+100.00\%$	$\color{green}61/61$ $\color{green}+100.00\%$	$\color{green}3/3$ $\color{green}+100.00\%$	$\color{green}582/582$ $\color{green}+100.00\%$

The above coverage report was generated for the changes in this PR.

[kgryte]

What about the case: indexOf( x, searchElement, fromIndex )?

[headlessNode]

We are handling options here. For indexOf( x, searchElement, fromIndex ) there is no options and we already intialized opts = {}.

So the below checks (before return) on searchElement and fromIndex handles this case correctly.

[kgryte]

Suggested change

- **fromIndex**: index from which to begin searching (_optional_). May be either a scalar value or an [ndarray][@stdlib/ndarray/ctor] having an `integer` or `generic` [data type][@stdlib/ndarray/dtypes]. If provided an [ndarray][@stdlib/ndarray/ctor], the value must have a shape which is [broadcast-compatible][@stdlib/ndarray/base/broadcast-shapes] with the complement of the shape defined by `options.dims`. For example, given the input shape `[2, 3, 4]` and `options.dims=[0]`, an [ndarray][@stdlib/ndarray/ctor] containing the index from which to begin searching must have a shape which is [broadcast-compatible][@stdlib/ndarray/base/broadcast-shapes] with the shape `[3, 4]`. Similarly, when performing the operation over all elements in a provided input [ndarray][@stdlib/ndarray/ctor], an [ndarray][@stdlib/ndarray/ctor] containing the index from which to begin searching must be a zero-dimensional [ndarray][@stdlib/ndarray/ctor]. By default, the the index from which to begin searching is `0`.

- **fromIndex**: index from which to begin searching (_optional_). May be either a scalar value or an [ndarray][@stdlib/ndarray/ctor] having an `integer` or `generic` [data type][@stdlib/ndarray/dtypes]. If provided an [ndarray][@stdlib/ndarray/ctor], the value must have a shape which is [broadcast-compatible][@stdlib/ndarray/base/broadcast-shapes] with the complement of the shape defined by `options.dims`. For example, given the input shape `[2, 3, 4]` and `options.dims=[0]`, an [ndarray][@stdlib/ndarray/ctor] containing the index from which to begin searching must have a shape which is [broadcast-compatible][@stdlib/ndarray/base/broadcast-shapes] with the shape `[3, 4]`. Similarly, when performing the operation over all elements in a provided input [ndarray][@stdlib/ndarray/ctor], an [ndarray][@stdlib/ndarray/ctor] containing the index from which to begin searching must be a zero-dimensional [ndarray][@stdlib/ndarray/ctor]. By default, the index from which to begin searching is `0`.

[kgryte]

Suggested change

	- **dtype**: output ndarray [data type][@stdlib/ndarray/dtypes]. Must be an "integer_index_and_generic" [data type][@stdlib/ndarray/dtypes].
	- **dtype**: output ndarray [data type][@stdlib/ndarray/dtypes]. Must be an integer or generic [data type][@stdlib/ndarray/dtypes].

[kgryte]

Suggested change

- **fromIndex**: index from which to begin searching (_optional_). May be either a scalar value or an [ndarray][@stdlib/ndarray/ctor] having an `integer` or `generic` [data type][@stdlib/ndarray/dtypes]. If provided an [ndarray][@stdlib/ndarray/ctor], the value must have a shape which is [broadcast-compatible][@stdlib/ndarray/base/broadcast-shapes] with the complement of the shape defined by `options.dims`. For example, given the input shape `[2, 3, 4]` and `options.dims=[0]`, an [ndarray][@stdlib/ndarray/ctor] containing the index from which to begin searching must have a shape which is [broadcast-compatible][@stdlib/ndarray/base/broadcast-shapes] with the shape `[3, 4]`. Similarly, when performing the operation over all elements in a provided input [ndarray][@stdlib/ndarray/ctor], an [ndarray][@stdlib/ndarray/ctor] containing the index from which to begin searching must be a zero-dimensional [ndarray][@stdlib/ndarray/ctor]. By default, the the index from which to begin searching is `0`.

- **fromIndex**: index from which to begin searching (_optional_). May be either a scalar value or an [ndarray][@stdlib/ndarray/ctor] having an `integer` or `generic` [data type][@stdlib/ndarray/dtypes]. If provided an [ndarray][@stdlib/ndarray/ctor], the value must have a shape which is [broadcast-compatible][@stdlib/ndarray/base/broadcast-shapes] with the complement of the shape defined by `options.dims`. For example, given the input shape `[2, 3, 4]` and `options.dims=[0]`, an [ndarray][@stdlib/ndarray/ctor] containing the index from which to begin searching must have a shape which is [broadcast-compatible][@stdlib/ndarray/base/broadcast-shapes] with the shape `[3, 4]`. Similarly, when performing the operation over all elements in a provided input [ndarray][@stdlib/ndarray/ctor], an [ndarray][@stdlib/ndarray/ctor] containing the index from which to begin searching must be a zero-dimensional [ndarray][@stdlib/ndarray/ctor]. By default, the index from which to begin searching is `0`.

[kgryte]

Copy-paste error. We are not computing the cumulative sum.

[kgryte]

Suggested change

	throw new TypeError( format( 'invalid argument. The function must be provided at least two arguments. Value: `%s`.', nargs ) );
	throw new TypeError( format( 'invalid argument. The function must be provided at least three arguments. Value: `%s`.', nargs ) );

[kgryte]

Missing out argument validation.