Recommendation

Recommended

Link

http://alvie.algoritmica.org/

Delivery Method

Java Application

License

By Request

Language

English

Author

Pilu Crescenzi

Institution

University of Florence

Project

ALVIE

RelationshipToProject

PartOfProject

Works

Yes

Description

Demonstrates a divide and conquer algorithm for computing the closest pair of points within a specified set of points in the Euclidean plane. C-like pseudo-code is included. The visualization tries to mimic as far as possible the animation of the algorithm used by Prof. Ottmann at the University of Freiburg. The visualization shows both the horizontal and the vertical strips used during the merge operation and it uses color to distinguish nodes within a vertical/horizontal strip from nodes out of the strip. Colors are also used to emphasize which nodes and distances are currently under examination. The user can go backward and forward, can zoom in and zoom out, and can set bookmarks. This visualization is easily configurable and localizable.

Evaluation

Simple-to-use user interface for walking through the example, since a good example is already provided with the algorithm. Simply open up the AV (see directions below) and step through the example with pseudo-code. Not clear if one can add data for this particular AV (you can for other ALVIE AVs). As you go through the example, you are directed to the corresponding line in the pseudocode and given a line or two of explanation in the message window. Attractive layout of the data, including colors indicating the current points being considered and an indication of the strip of area within the current maximum distance.

ActivityLevel

Step Control; Canned Data

GoodFor

Lecture Aid; Self Study

Screenshots

Videos

References

HowToUse

Download and unzip the ALVIE system from the website. Double click on the .jar file. Within the ALVIE pane (not the GRIND pane), click on the "eye" icon (third icon from the left in the toolbar) to get a list of algorithms from which selecting the Closest Pair of Points. Once selected, click OK and step through the AV with the arrow icons.

First Visited

2009-07-20

Last Visited

2009-07-20

Last Updated

Topic

ComputationalGeometry

Community

Comments

Edit

You may edit this entry if you have an account.