Rank: 2317 based on 56 downloads (last 30 days) and 3 files submitted
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Zacharias Voulgaris

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21 Jan 2010 Efficient convertors between binary and decimal numbers Alternatives to the built-in functions bin2dec & dec2bin, exhibiting a somewhat faster performance. Author: Zacharias Voulgaris binary, decimal, conversion 25 4
  • 4.5
4.5 | 2 ratings
20 Jan 2010 Number of classes A practical tool for finding quickly the classes of a dataset based on the labels array. Author: Zacharias Voulgaris unique values, class labels, class vector 6 3
20 Jan 2010 Distance Matrix calculation A compact program for calculating the distances of a group of points, given as rows in a matrix. Author: Zacharias Voulgaris distance calculation, euclidean distance 25 3
  • 3.5
3.5 | 2 ratings
Comments and Ratings by Zacharias Voulgaris View all
Updated File Comments Rating
03 Mar 2010 Particle Swarm Optimization Toolbox With Trelea, Common, and Clerc types along with ... Author: Brian Birge

I am also interested in discrete PSO for TSP. If anyone has something in Matlab, please contact me. Thanks.

03 Mar 2010 Munkres Assignment Algorithm An efficient implementation of the Munkres algorithm for the assignment problem. Author: Yi Cao

Truly excellent. It has everything you could ask of a Matlab program: good structure, excellent comments, simplicity, flow and efficiency. Thank you for sharing.

21 Jan 2010 Number of classes A practical tool for finding quickly the classes of a dataset based on the labels array. Author: Zacharias Voulgaris

Thank you for your feedback.

It is true that there are different ways of going about this problem, one of which is using the unique function. However, the whole idea of developing the nc program was to avoid the "unique" function as it is slower. Note that the speed of a function is more accurately measured via the profiler program of Matlab, or through the cputime function.

21 Jan 2010 spheresegmentvolume Volume of a (hyper)sphere, sphere cap, or any band through a sphere defined by two parallel planes Author: John D'Errico

An excellent piece of work. I particularly liked the clear line of thought through the code (mirrored in its simplicity), as well as the abundance of comments.
Thank you for sharing.

Comments and Ratings on Zacharias Voulgaris' Files View all
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16 May 2013 Distance Matrix calculation A compact program for calculating the distances of a group of points, given as rows in a matrix. Author: Zacharias Voulgaris dali elite

thanks

28 Dec 2012 Efficient convertors between binary and decimal numbers Alternatives to the built-in functions bin2dec & dec2bin, exhibiting a somewhat faster performance. Author: Zacharias Voulgaris Rakshit Kothari

Brilliant! if anyone is looking for a FAST decimal to binary / binary to decimal converter, this is the one - please don't use bi2de or de2bi.

This tremendously increased my performance,
thank you
Zacharias Voulgaris

22 Mar 2012 Efficient convertors between binary and decimal numbers Alternatives to the built-in functions bin2dec & dec2bin, exhibiting a somewhat faster performance. Author: Zacharias Voulgaris Marc Lalancette

Actually, the bug was for any power of 2 (1, 2, 4, ...). Ali's modification works, but a more elegant fix is:
c = floor(log2(x)) + 1;
No need for any other modification from original code (no special case for 1, no need to remove preceding zeros).

14 Mar 2011 Efficient convertors between binary and decimal numbers Alternatives to the built-in functions bin2dec & dec2bin, exhibiting a somewhat faster performance. Author: Zacharias Voulgaris Ali

More correct version:

function y = d2b(x)

% Convert a decimanl number into a binary array
%
% Similar to dec2bin but yields a numerical array instead of a string and is found to
% be rather faster

if x==1
y=1;
return
end

c = ceil(log(x)/log(2)) + 1; % Number of divisions necessary ( rounding up the log2(x) )
y(c) = 0; % Initialize output array
for i = 1:c
r = floor(x / 2);
y(c+1-i) = x - 2*r;
x = r;
end

% If there is a preceding one, remove it.
if(y(1) == 0)
y(1) = [];
end

30 Sep 2010 Efficient convertors between binary and decimal numbers Alternatives to the built-in functions bin2dec & dec2bin, exhibiting a somewhat faster performance. Author: Zacharias Voulgaris Roberto Olmi

A little bug for the trivial input value: x=1. Add these lines to fix:
if x==1
y=1;
return
end

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