TISEAN package: Difference between revisions

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== Porting TISEAN ==
== Porting TISEAN ==


This section describes the process employed during porting TISEAN package into an Octave Package. This project was started as part of the Google Summer of Code 2015.
This section will focus on demonstrating the capabilities of the TISEAN package. The previous information about the porting procedure has been moved [[TISEAN_package:Procedure|here]].


The current progress can be viewed [[User:Josiah425:TISEAN_Package:Table_of_functions| here]].


To aid in understanding the task there are some charts.
== Tutorials ==
 
These tutorials are based on examples, tutorials and the articles located on the TISEAN website:<br/> [http://www.mpipks-dresden.mpg.de/~tisean/Tisean_3.0.1/ http://www.mpipks-dresden.mpg.de/~tisean/Tisean_3.0.1/].<br/>
The first chart depicts what to do with each function in the function table. I mainly focuses on those functions that might already implemented in Octave.
This tutorial will utilize the following dataset:
 
* [http://www.mpipks-dresden.mpg.de/~tisean/Tisean_3.0.1/docs/tutorial/amplitude.dat amplitude.dat]
[[File:Work_flow_TISEAN.png]]
Please download it as the tutorial functions will reference it.
 
=== Noise Reduction ===
The chart below depicts how to decide which type of port should be utilized.
This tutorial show different methods of the 'Noise Reduction' section of the TISEAN documentation (located [http://www.mpipks-dresden.mpg.de/~tisean/Tisean_3.0.1/docs/chaospaper/node22.html#SECTION00060000000000000000 here]). It shows the use of simple nonlinear noise reduction (function {{Codeline|lazy}}) and locally projective nonlinear noise reduction (function {{Codeline|ghkss}}). To start let's create noisy data to work with.
 
{{Code|Creating a noisy henon map|<syntaxhighlight lang="octave" style="font-size:13px">
[[File:Porting_Programs_TISEAN.png]]
hen      = henon (10000);
 
hen      = hen(:,1); # We only need the first column
Both of those charts can be combined into a large one that shows all of the work together.
hen_noisy = hen + std (hen) * 0.02 .* (-6 + sum (rand ([size(hen), 12]), 3));
 
</syntaxhighlight>}}
[[File:Flow_Together_TISEAN.png]]
This created a Henon map contaminated by 2% Gaussian noise à la TISEAN. In the tutorials and exercises  on the TISEAN website this would be equivalent to calling {{Codeline|makenoise -%2}} on the Henon map.<br/>
Next we will reduce the noise using simple nonlinear noise reduction {{Codeline|lazy}}.
{{Code|Simple nonlinear noise reduction|<syntaxhighlight lang="octave" style="font-size:13px">
clean      = lazy (hen_noisy,7,-0.06,3);
# Create delay vectors for both the clean and noisy data
delay_clean = delay (clean);
delay_noisy = delay (hen_noisy);
# Plot both on one chart
plot (delay_noisy(:,1), delay_noisy(:,2), 'b.;Noisy Data;','markersize,3,...
      delay_clean(:,1), delay_clean(:,2), 'r.;Clean Data;','markersize,3)
</syntaxhighlight>}}
On the chart created the red dots represent cleaned up data. It is much closer to the original than the noisy set.<br/>
Now we will do the same, only with {{Codeline|ghkss}}.
{{Code|Locally projective nonlinear noise reduction|<syntaxhighlight lang="octave" style="font-size:13px">
clean      = ghkss (hen(:,1),'m',7,'q',2,'r',0.05,'k',20,'i',2);
# Create delay vectors for both the clean and noisy data
delay_clean = delay (clean);
delay_noisy = delay (hen_noisy);
# Plot both on one chart
plot (delay_noisy(:,1), delay_noisy(:,2), 'b.;Noisy Data;','markersize,3,...
      delay_clean(:,1), delay_clean(:,2), 'r.;Clean Data;','markersize,3)
</syntaxhighlight>}}


[[Category:Octave-Forge]]
[[Category:Octave-Forge]]

Revision as of 17:35, 1 June 2015

Porting TISEAN

This section will focus on demonstrating the capabilities of the TISEAN package. The previous information about the porting procedure has been moved here.


Tutorials

These tutorials are based on examples, tutorials and the articles located on the TISEAN website:
http://www.mpipks-dresden.mpg.de/~tisean/Tisean_3.0.1/.
This tutorial will utilize the following dataset:

Please download it as the tutorial functions will reference it.

Noise Reduction

This tutorial show different methods of the 'Noise Reduction' section of the TISEAN documentation (located here). It shows the use of simple nonlinear noise reduction (function lazy) and locally projective nonlinear noise reduction (function ghkss). To start let's create noisy data to work with.

Code: Creating a noisy henon map
hen       = henon (10000);
hen       = hen(:,1); # We only need the first column
hen_noisy = hen + std (hen) * 0.02 .* (-6 + sum (rand ([size(hen), 12]), 3));

This created a Henon map contaminated by 2% Gaussian noise à la TISEAN. In the tutorials and exercises on the TISEAN website this would be equivalent to calling makenoise -%2 on the Henon map.
Next we will reduce the noise using simple nonlinear noise reduction lazy.

Code: Simple nonlinear noise reduction
clean       = lazy (hen_noisy,7,-0.06,3);
# Create delay vectors for both the clean and noisy data
delay_clean = delay (clean);
delay_noisy = delay (hen_noisy);
# Plot both on one chart
plot (delay_noisy(:,1), delay_noisy(:,2), 'b.;Noisy Data;','markersize,3,...
      delay_clean(:,1), delay_clean(:,2), 'r.;Clean Data;','markersize,3)

On the chart created the red dots represent cleaned up data. It is much closer to the original than the noisy set.
Now we will do the same, only with ghkss.

Code: Locally projective nonlinear noise reduction
clean       = ghkss (hen(:,1),'m',7,'q',2,'r',0.05,'k',20,'i',2);
# Create delay vectors for both the clean and noisy data
delay_clean = delay (clean);
delay_noisy = delay (hen_noisy);
# Plot both on one chart
plot (delay_noisy(:,1), delay_noisy(:,2), 'b.;Noisy Data;','markersize,3,...
      delay_clean(:,1), delay_clean(:,2), 'r.;Clean Data;','markersize,3)

External links