WOLFRAM

Wolfram 语言与系统参考资料中心

SWAP[x,y]

swaps contents of the vectors x and y.

更多信息和选项
Details and Options Details and Options
范例  
基本范例  
Scope  
Generalizations & Extensions  
Properties & Relations  
Possible Issues  
相关指南
按以下格式引用：
LinearAlgebra`BLAS`
LinearAlgebra`BLAS`

SWAP

SWAP[x,y]

swaps contents of the vectors x and y.

更多信息和选项

  • To use SWAP, you first need to load the BLAS Package using Needs["LinearAlgebra`BLAS`"].
  • The following arguments must be given:
  • xinput/output symbolvector; the symbol value is modified in place
    yinput/output symbolvector; the symbol value is modified in place
  • SWAP[x,y] is equivalent to {x,y}={y,x}.
  • The vector arguments must be of the same length.

范例

打开所有单元 关闭所有单元

基本范例  (1)

Load the BLAS package:

Wolfram Language code: Needs["LinearAlgebra`BLAS`"]

Swap two vectors :

Wolfram Language code: x = {1, 2, 3}; y = {-1, 0, 1}; SWAP[x, y]; {x, y}

Scope  (4)

Real vectors:

Wolfram Language code: x = {1.2, -3.1, 0.4}; y = {-2.9, 1.6, 2.2}; SWAP[x, y]; {x, y}

Complex vectors:

Wolfram Language code: x = {2.I, -3. + 1.2I, 3.}; y = {0.4 + 7.3I, 2.2, 2.1I}; SWAP[x, y]; {x, y}

Arbitrary-precision vectors:

Wolfram Language code: x = {1`20, 2, 3}; y = {-1`20, 0, 1}; SWAP[x, y]; {x, y}

Symbolic vectors:

Wolfram Language code: x = {v1, v2, v3}; y = {w1, w2, w3}; SWAP[x, y]; {x, y}

Generalizations & Extensions  (2)

Swap the first two rows of a matrix in place:

Wolfram Language code: m = Array[a, {3, 3}]; SWAP[m[[1]], m[[2]]]; m//MatrixForm

Swap the second and third columns of a matrix in place:

Wolfram Language code: m = Array[a, {3, 3}]; SWAP[m[[All, 2]], m[[All, 3]]]; m//MatrixForm

Properties & Relations  (1)

SWAP[x,y] is equivalent to {x,y}={y,x}:

Wolfram Language code: x = x1 = RandomReal[1, {5}]; y = y1 = RandomReal[1, {5}]; SWAP[x, y]; {x, y} == {y1, x1}

Possible Issues  (3)

The arguments must be symbols:

Wolfram Language code: SWAP[{1, 2}, {3, 4}]

The arguments must be initialized to vectors:

Wolfram Language code: Clear[x, y]; SWAP[x, y]

The arguments must be of equal length:

Wolfram Language code: x = {1, 2}; y = {3, 4, 5}; SWAP[x, y]
Wolfram Research (2017)，SWAP，Wolfram 语言函数，https://reference.wolfram.com/language/LowLevelLinearAlgebra/ref/SWAP.html.

文本

Wolfram Research (2017)，SWAP，Wolfram 语言函数，https://reference.wolfram.com/language/LowLevelLinearAlgebra/ref/SWAP.html.

CMS

Wolfram 语言. 2017. "SWAP." Wolfram 语言与系统参考资料中心. Wolfram Research. https://reference.wolfram.com/language/LowLevelLinearAlgebra/ref/SWAP.html.

APA

Wolfram 语言. (2017). SWAP. Wolfram 语言与系统参考资料中心. 追溯自 https://reference.wolfram.com/language/LowLevelLinearAlgebra/ref/SWAP.html 年

BibTeX

@misc{reference.wolfram_2026_swap, author="Wolfram Research", title="{SWAP}", year="2017", howpublished="\url{https://reference.wolfram.com/language/LowLevelLinearAlgebra/ref/SWAP.html}", note=[Accessed: 26-June-2026]}

BibLaTeX

@online{reference.wolfram_2026_swap, organization={Wolfram Research}, title={SWAP}, year={2017}, url={https://reference.wolfram.com/language/LowLevelLinearAlgebra/ref/SWAP.html}, note=[Accessed: 26-June-2026]}