Rank: 430 based on 140 downloads (last 30 days) and 12 files submitted
photo

Zachary Danziger

E-mail
Company/University
Duke University

Personal Profile:

Postdoctoral researcher in neuroscience.

Web: https://sites.google.com/site/zdanziger/home

Professional Interests:
computational motor control

 

Watch this Author's files

 

Files Posted by Zachary View all
Updated   File Tags Downloads
(last 30 days)
Comments Rating
30 May 2013 Screenshot Discrete Frechet Distance The discrete Frechet distance is a scalar measure of similarity between two curves. Author: Zachary Danziger curves, mathematics, metric, similarity, measure, frechet 28 15
  • 4.5
4.5 | 3 ratings
03 Apr 2013 Screenshot Text Yahtzee Play Yahtzee in the command window, with multiple players per game. Author: Zachary Danziger games, game 3 0
  • 5.0
5.0 | 1 rating
03 Apr 2013 Screenshot Hausdorff Distance Calculates the Hausdorff Distance between two sets of points in a Euclidean metric space. Author: Zachary Danziger distance, mathematics, metric, trajectory similarity 69 4
  • 4.25
4.2 | 4 ratings
03 Apr 2013 Screenshot Variable Frequency Sine Wave Create a sine wave by defining the frequency over a series of intervals. Author: Zachary Danziger mathematics 7 0
31 Jul 2012 Screenshot ChessPeace Software for playing Chess and Chess Variants Author: Zachary Danziger game, games, chess, artificial intelligen..., ai, graphics 12 0
Comments and Ratings by Zachary View all
Updated File Comments Rating
17 Jul 2013 Discrete Frechet Distance The discrete Frechet distance is a scalar measure of similarity between two curves. Author: Zachary Danziger

Leyon,
The Frechet Distance, which this code approximates, is only defined for 2 curves. However, I am sure that some one cleverer than I could think of a way...

04 Jun 2013 Discrete Frechet Distance The discrete Frechet distance is a scalar measure of similarity between two curves. Author: Zachary Danziger

Arthur,
If you are just looking for the standard Euclidean distance you can leave off the dfcn argument and it will be used by default.

Otherwise it expects a function handle. The 'ordinary' distance function is passed as:
dfcn = @(p,q) sqrt(sum( (p-q).^2 ));

But any function will work that operates on points p and q that respects their dimensionality. A Chebyshev-like measure could be used, for example:
dcheb = @(p,q) max(abs(p-q))

29 May 2013 Discrete Frechet Distance The discrete Frechet distance is a scalar measure of similarity between two curves. Author: Zachary Danziger

Thanks for all your help Lingji, it's certainly a better tool now.

24 May 2013 Discrete Frechet Distance The discrete Frechet distance is a scalar measure of similarity between two curves. Author: Zachary Danziger

Lingji,

I cannot see a way to calculate the coupling distance during the recursive calls to c(i,j) without additional overhead. I feel that adding computational cost is not justified because, in general, the coupling sequence is not unique and therefore is not especially informative. The coupling sequence is just any allowable (i.e., follows the forward movement rules) sequence between points on P and Q that never has distance greater than cm. In the typical case there are a great many allowable sequences because interchanging many points with small distances does not affect cm if there is a much larger distance later in the sequence.

Here is my compromise: if the user requests the coupling sequence then I calculate the cm as usual, and at the end of the code I loop through the CA variable choosing one workable coupling sequence. I hope this pleases the fans.

17 May 2013 Discrete Frechet Distance The discrete Frechet distance is a scalar measure of similarity between two curves. Author: Zachary Danziger

Lingji,
Thanks for the suggestions. What is the best way to tell when the algorithm has moved to the next point in the chain ("the next time") without storing the data for every recursion?

Comments and Ratings on Zachary's Files View all
Updated File Comment by Comments Rating
17 Jul 2013 Discrete Frechet Distance The discrete Frechet distance is a scalar measure of similarity between two curves. Author: Zachary Danziger Danziger, Zachary

Leyon,
The Frechet Distance, which this code approximates, is only defined for 2 curves. However, I am sure that some one cleverer than I could think of a way...

17 Jul 2013 Discrete Frechet Distance The discrete Frechet distance is a scalar measure of similarity between two curves. Author: Zachary Danziger Leyon

Is it possible to use this script to sample more than 2 curves?

04 Jun 2013 Discrete Frechet Distance The discrete Frechet distance is a scalar measure of similarity between two curves. Author: Zachary Danziger Danziger, Zachary

Arthur,
If you are just looking for the standard Euclidean distance you can leave off the dfcn argument and it will be used by default.

Otherwise it expects a function handle. The 'ordinary' distance function is passed as:
dfcn = @(p,q) sqrt(sum( (p-q).^2 ));

But any function will work that operates on points p and q that respects their dimensionality. A Chebyshev-like measure could be used, for example:
dcheb = @(p,q) max(abs(p-q))

04 Jun 2013 Discrete Frechet Distance The discrete Frechet distance is a scalar measure of similarity between two curves. Author: Zachary Danziger Allen, Arthur

Zach and Lingi; I would like to compare two drifter tracks (lat, long pairs). I tried using 'distance' from the Mapping Toolbox, but this dosn't work. Can you provide an example of dfcn function that does work? Thanks,

29 May 2013 Discrete Frechet Distance The discrete Frechet distance is a scalar measure of similarity between two curves. Author: Zachary Danziger Danziger, Zachary

Thanks for all your help Lingji, it's certainly a better tool now.

Top Tags Applied by Zachary
mathematics, games, matrix, linear algebra, entertainment
Files Tagged by Zachary View all
Updated   File Tags Downloads
(last 30 days)
Comments Rating
30 May 2013 Screenshot Discrete Frechet Distance The discrete Frechet distance is a scalar measure of similarity between two curves. Author: Zachary Danziger curves, mathematics, metric, similarity, measure, frechet 28 15
  • 4.5
4.5 | 3 ratings
03 Apr 2013 Screenshot Text Yahtzee Play Yahtzee in the command window, with multiple players per game. Author: Zachary Danziger games, game 3 0
  • 5.0
5.0 | 1 rating
03 Apr 2013 Screenshot Hausdorff Distance Calculates the Hausdorff Distance between two sets of points in a Euclidean metric space. Author: Zachary Danziger distance, mathematics, metric, trajectory similarity 69 4
  • 4.25
4.2 | 4 ratings
03 Apr 2013 Screenshot Variable Frequency Sine Wave Create a sine wave by defining the frequency over a series of intervals. Author: Zachary Danziger mathematics 7 0
31 Jul 2012 Screenshot ChessPeace Software for playing Chess and Chess Variants Author: Zachary Danziger game, games, chess, artificial intelligen..., ai, graphics 12 0

Contact us