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PseudoDiameter[g]

give the pseudo-diameter of the undirected graph g, and the two vertices that achieve this diameter.

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范例  
基本范例  
Scope  
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按以下格式引用：
GraphUtilities`
GraphUtilities`

PseudoDiameter

As of Version 10, all the functionality of the GraphUtilities package is built into the Wolfram System. »

PseudoDiameter[g]

give the pseudo-diameter of the undirected graph g, and the two vertices that achieve this diameter.

更多信息和选项

  • PseudoDiameter functionality is now available in the built-in Wolfram Language function GraphDiameter.
  • To use PseudoDiameter, you first need to load the Graph Utilities Package using Needs["GraphUtilities`"].
  • A graph geodesic is a shortest path between two vertices of a graph. The graph diameter is the longest possible length of all graph geodesics of the graph. PseudoDiameter finds an approximate graph diameter. It works by starting from a vertex u, and finds a vertex v that is farthest away from u. This process is repeated by treating v as the new starting vertex, and ends when the graph distance no longer increases. A vertex from the last level set that has the smallest degree is chosen as the final starting vertex u, and a traversal is done to see if the graph distance can be increased. This graph distance is taken to be the pseudo-diameter.
  • If the graph is disconnected, then the diameter and vertices for each connected component are returned.
  • The following option can be given:
  • AggressiveFalsewhether to make extra effort in finding the optimal graph diameter

范例

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基本范例  (2)

Wolfram Language code: Needs["GraphUtilities`"]

The pseudo-diameter of the graph of a square is 2:

Wolfram Language code: g = {1 -> 2, 2 -> 3, 3 -> 4, 4 -> 1};
Wolfram Language code: PseudoDiameter[g]

PseudoDiameter has been superseded by GraphDiameter:

Wolfram Language code: g = Graph[{12, 23, 34, 41}];
Wolfram Language code: {GraphDiameter[g, Method -> "PseudoDiameter"], GraphPeriphery[g, Method -> "PseudoDiameter"]}

Scope  (1)

Wolfram Language code: Needs["GraphUtilities`"]

A graph with disconnected components:

Wolfram Language code: g = {1 -> 2, 2 -> 3, 4 -> 5}

PseudoDiameter returns a list with pseudo-diameters and vertices for each component:

Wolfram Language code: PseudoDiameter[g]
Wolfram Research (2007)，PseudoDiameter，Wolfram 语言函数，https://reference.wolfram.com/language/GraphUtilities/ref/PseudoDiameter.html.

文本

Wolfram Research (2007)，PseudoDiameter，Wolfram 语言函数，https://reference.wolfram.com/language/GraphUtilities/ref/PseudoDiameter.html.

CMS

Wolfram 语言. 2007. "PseudoDiameter." Wolfram 语言与系统参考资料中心. Wolfram Research. https://reference.wolfram.com/language/GraphUtilities/ref/PseudoDiameter.html.

APA

Wolfram 语言. (2007). PseudoDiameter. Wolfram 语言与系统参考资料中心. 追溯自 https://reference.wolfram.com/language/GraphUtilities/ref/PseudoDiameter.html 年

BibTeX

@misc{reference.wolfram_2026_pseudodiameter, author="Wolfram Research", title="{PseudoDiameter}", year="2007", howpublished="\url{https://reference.wolfram.com/language/GraphUtilities/ref/PseudoDiameter.html}", note=[Accessed: 18-August-2026]}

BibLaTeX

@online{reference.wolfram_2026_pseudodiameter, organization={Wolfram Research}, title={PseudoDiameter}, year={2007}, url={https://reference.wolfram.com/language/GraphUtilities/ref/PseudoDiameter.html}, note=[Accessed: 18-August-2026]}