pca

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Principal Component Analysis
 
Principal Component Analysis
 
   
 
   
Compute the principal components of a three band [[byte]] image
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Compute the principal components of an N band real data image
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NOTE: for the old 3 band pca version see [[pca_byte|pca_byte()]].  This version replaced the old byte version on 2-9-2011
 
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Arguments: A numeric array and ignore value
 
Arguments: A numeric array and ignore value
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Return Value: The rotated data
 
Return Value: The rotated data
 
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[[Syntax]]: pca(image)
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[[Syntax]]: pca(image [, ignore=FLOAT][, struct=BOOL])
 
   
 
   
'image' - A 3-band (z-dimension=3) numeric array
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'image' - A N-band image or data array
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'ignore' - the ignore value for the black space of an image
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'struct' - return the eigen vectors/values and covariance matrix
 
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  dv> a
 
  dv> a
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*[[pca2]]
 
*[[pca2]]
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*[[pca_byte]]
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*[[eigen2]]
 
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*general_science.dvrc
 
*general_science.dvrc
 
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1.02
 
}}
 
}}
 
[[category:Functions]]
 
[[category:Functions]]
 
[[category:User Defined Functions]]
 
[[category:User Defined Functions]]
 
[[category:Matrix]]
 
[[category:Matrix]]

Revision as of 13:23, 9 February 2011


Description

Principal Component Analysis

Compute the principal components of an N band real data image

NOTE: for the old 3 band pca version see pca_byte(). This version replaced the old byte version on 2-9-2011

Arguments and Return Values

Arguments: A numeric array and ignore value

Return Value: The rotated data

Usage

dv> a
600x600x3 array of byte, bip format [1,080,000 bytes]

dv> b=pca(a)
  data: 600x600x3 array of double, bip format [8,640,000 bytes]

Examples

Original Image

unfiltered.png

Three principal components

comp1.png comp2.png comp3.png

Images

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Contents


Contact Developers

  • davinci-dev [AT] mars.asu.edu

All other topics

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Major Sub-Functions

Related Functions

  • general_science.dvrc

Recent Library Changes

Created On: 02-15-2006
Modified On: 07-16-2012

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