Add a useful package (from Source forge) for octave

[CreaPhase.git] / octave_packages / communications-1.1.1 / fiboenco.m

diff --git a/octave_packages/communications-1.1.1/fiboenco.m b/octave_packages/communications-1.1.1/fiboenco.m
new file mode 100644 (file)
index 0000000..c17346a
--- /dev/null
+++ b/octave_packages/communications-1.1.1/fiboenco.m
@@ -0,0 +1,89 @@
+## Copyright (C) 2006 Muthiah Annamalai <muthiah.annamalai@uta.edu>
+##
+## This program is free software; you can redistribute it and/or modify it under
+## the terms of the GNU General Public License as published by the Free Software
+## Foundation; either version 3 of the License, or (at your option) any later
+## version.
+##
+## This program is distributed in the hope that it will be useful, but WITHOUT
+## ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+## FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
+## details.
+##
+## You should have received a copy of the GNU General Public License along with
+## this program; if not, see <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {} fiboenco (@var{num})
+## 
+## Returns the cell-array of encoded fibonacci value from the column vectors @var{num}.
+## Universal codes like fibonacci codes have a useful synchronization
+## property, only for 255 maximum value we have designed these routines. We assume
+## user has partitioned the code into several unique segments based on
+## the suffix property of unique elements [1 1] and we just decode the
+## parts. Partitioning the stream is as simple as identifying the [1 1]
+## pairs that occur, at the terminating ends. This system implements
+## the standard binaary Fibonacci codes, which means that row vectors
+## can only contain 0 or 1. Ref: http://en.wikipedia.org/wiki/Fibonacci_coding
+## Ugly O(k.N^2) encoder.Ref: Wikipedia article accessed March, 2006.
+## @url{http://en.wikipedia.org/wiki/Fibonacci_coding},  UCI Data Compression
+## Book, @url{http://www.ics.uci.edu/~dan/pubs/DC-Sec3.html}, (accessed 
+## October 2006)
+## 
+## @example
+## @group
+##      fiboenco(10) #=  code is @{[ 0 1 0 0 1 1]@}
+##      fiboenco(1:4) #= code is @{[1 1],[0 1 1],[0 0 1 1],[1 0 1 1]@}
+## @end group
+## @end example
+## @end deftypefn
+## @seealso{fibodeco}
+
+function op_num=fiboenco(num)
+     %
+     % generate fibonacci series table.
+     %
+     % f(1)=1;
+     % f(2)=1;
+     %
+     % while ((f(end-1)+f(end)) < 256)
+     %     val=(f(end-1)+f(end));
+     %     f=[f val];
+     % end
+     % f=sort(f(2:end),"descend");
+     %
+
+     %f= [75025   46368   28657   17711   10946    6765    4181    2584 \
+     %  1597     987    610     377     233     144      89      55 \
+     %  34      21      13   8       5       3       2       1];
+     
+     if(nargin < 1) || (min(num) <= 0 || max(num) > 608)
+       error("Usage:fiboenco(num), where num is +ve sequence of numbers ...
+       and less than equal to 608");
+     end
+     f= [ 233   144    89    55    34    21    13     8     5     3     2     1];
+     
+     onum=num;
+     LEN_F=length(f);
+     LEN_N=length(num);
+     
+     for j=1:LEN_N
+       N=num(j);
+       rval=[];
+
+       %create Fibonacci encoding of a number
+       for i=find(f<=N):LEN_F
+        if(N >= f(i))
+          N=N-f(i);
+          rval=[1 rval];
+        else
+          rval=[0 rval];
+        end
+       end      
+       op_num{j}=[rval 1];
+     end
+     return
+end
+%!
+%!assert(fibodeco(fiboenco(1:600)),[1:600])
+%!