/*
* @license Apache-2.0
*
* Copyright (c) 2020 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*    http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/

// TypeScript Version: 4.1

/// <reference types="@stdlib/types"/>

import { float64ndarray } from '@stdlib/types/ndarray';

/**
* Computes the dot product of two double-precision floating-point vectors.
*
* ## Notes
*
* -   If provided at least one input array having more than one dimension, the input arrays are broadcasted to a common shape.
* -   For multi-dimensional input arrays, the function performs batched computation, such that the function computes the dot product for each pair of vectors in `x` and `y` according to the specified dimension index.
* -   The size of the contracted dimension must be the same for both input arrays.
* -   The function resolves the dimension index for which to compute the dot product **before** broadcasting.
* -   If provided empty vectors, the dot product is `0`.
* -   Negative indices are resolved relative to the last array dimension, with the last dimension corresponding to `-1`.
* -   The output array has the same data type as the input arrays and has a shape which is determined by broadcasting and excludes the contracted dimension.
*
* @param x - first input array
* @param y - second input array
* @param dim - dimension for which to compute the dot product (default: -1)
* @throws first argument must be a non-zero-dimensional ndarray containing double-precision floating-point numbers
* @throws second argument must be a non-zero-dimensional ndarray containing double-precision floating-point numbers
* @throws input arrays must be broadcast-compatible
* @throws the size of the contracted dimension must be the same for both input arrays
* @returns dot product
*
* @example
* var Float64Array = require( '@stdlib/array/float64' );
* var array = require( '@stdlib/ndarray/array' );
*
* var x = array( new Float64Array( [ 4.0, 2.0, -3.0, 5.0, -1.0 ] ) );
* var y = array( new Float64Array( [ 2.0, 6.0, -1.0, -4.0, 8.0 ] ) );
*
* var z = ddot( x, y );
* returns <ndarray>
*
* var v = z.get();
* // returns -5.0
*/
declare function ddot( x: float64ndarray, y: float64ndarray, dim?: number ): float64ndarray;


// EXPORTS //

export = ddot;