Source code for mars.tensor.linalg.vdot

#!/usr/bin/env python
# -*- coding: utf-8 -*-
# Copyright 1999-2021 Alibaba Group Holding Ltd.
# Licensed under the Apache License, Version 2.0 (the "License");
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from ..datasource import tensor as astensor
from .dot import dot

[docs]def vdot(a, b): """ Return the dot product of two vectors. The vdot(`a`, `b`) function handles complex numbers differently than dot(`a`, `b`). If the first argument is complex the complex conjugate of the first argument is used for the calculation of the dot product. Note that `vdot` handles multidimensional tensors differently than `dot`: it does *not* perform a matrix product, but flattens input arguments to 1-D vectors first. Consequently, it should only be used for vectors. Parameters ---------- a : array_like If `a` is complex the complex conjugate is taken before calculation of the dot product. b : array_like Second argument to the dot product. Returns ------- output : Tensor Dot product of `a` and `b`. Can be an int, float, or complex depending on the types of `a` and `b`. See Also -------- dot : Return the dot product without using the complex conjugate of the first argument. Examples -------- >>> import mars.tensor as mt >>> a = mt.array([1+2j,3+4j]) >>> b = mt.array([5+6j,7+8j]) >>> mt.vdot(a, b).execute() (70-8j) >>> mt.vdot(b, a).execute() (70+8j) Note that higher-dimensional arrays are flattened! >>> a = mt.array([[1, 4], [5, 6]]) >>> b = mt.array([[4, 1], [2, 2]]) >>> mt.vdot(a, b).execute() 30 >>> mt.vdot(b, a).execute() 30 >>> 1*4 + 4*1 + 5*2 + 6*2 30 """ a, b = astensor(a), astensor(b) return dot(a.conj().ravel(), b.ravel())