pca
| (7 intermediate revisions by 3 users not shown) | |||
| Line 2: | Line 2: | ||
Principal Component Analysis | Principal Component Analysis | ||
| − | Compute the principal components | + | Compute the principal components of an N band real data image |
| + | |||
| + | NOTE: for the old 3 band pca version see [[pca_byte|pca_byte()]]. This version replaced the old byte version on 2-9-2011 | ||
| | | | ||
Arguments: A numeric array and ignore value | Arguments: A numeric array and ignore value | ||
| Line 8: | Line 10: | ||
Return Value: The rotated data | Return Value: The rotated data | ||
| | | | ||
| − | [[Syntax]]: pca(image) | + | [[Syntax]]: pca(image [, ignore=FLOAT][, struct=BOOL]) |
| − | 'image' - A | + | 'image' - A N-band image or data array |
| − | + | ||
| − | 'ignore' - | + | 'ignore' - the ignore value for the black space of an image |
| + | |||
| + | 'struct' - return the eigen vectors/values and covariance matrix | ||
| | | | ||
dv> a | dv> a | ||
| Line 20: | Line 24: | ||
data: 600x600x3 array of double, bip format [8,640,000 bytes] | data: 600x600x3 array of double, bip format [8,640,000 bytes] | ||
| | | | ||
| − | Original Image | + | Original 3-band Image: |
[[Image:unfiltered.png|250px]] | [[Image:unfiltered.png|250px]] | ||
| − | Three principal components | + | Three principal components: |
[[Image:comp1.png|250px]] [[Image:comp2.png|250px]] [[Image:comp3.png|250px]] | [[Image:comp1.png|250px]] [[Image:comp2.png|250px]] [[Image:comp3.png|250px]] | ||
| + | |||
| + | Original 6-band Image: | ||
| + | |||
| + | [[Image:NYC-Band_Comparison.PNG|300px]] | ||
| + | |||
| + | Six principal components: | ||
| + | |||
| + | [[Image:NYC-PCA-C1.PNG|300px]] [[Image:NYC-PCA-C2.PNG|300px]] [[Image:NYC-PCA-C3.PNG|300px]] [[Image:NYC-PCA-C4.PNG|300px]] [[Image:NYC-PCA-C5.PNG|300px]] [[Image:NYC-PCA-C6.PNG|300px]] | ||
| + | |||
| | | | ||
*[[mxm]] | *[[mxm]] | ||
| Line 32: | Line 45: | ||
*[[covar]] | *[[covar]] | ||
| | | | ||
| + | *[[eigen2]] | ||
| + | *[[kt1]] | ||
| + | *[[kt2]] | ||
| + | *[[kt3]] | ||
| + | *[[kt4]] | ||
| + | *[[kt5]] | ||
| + | *[[kt6]] | ||
*[[pca2]] | *[[pca2]] | ||
| + | *[[pca_byte]] | ||
| | | | ||
| − | + | *general_science.dvrc | |
| | | | ||
| + | 1.02 | ||
}} | }} | ||
[[category:Functions]] | [[category:Functions]] | ||
[[category:User Defined Functions]] | [[category:User Defined Functions]] | ||
[[category:Matrix]] | [[category:Matrix]] | ||
Latest revision as of 17:36, 15 July 2012
|
Contents: Description, Arguments, Usage, Examples, Images, Sub-Functions, Related Functions, Source Supported Under Version: > 1.02
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 Syntax: pca(image [, ignore=FLOAT][, struct=BOOL]) 'image' - A N-band image or data array 'ignore' - the ignore value for the black space of an image 'struct' - return the eigen vectors/values and covariance matrix
Examples 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]
Images Original 3-band Image:
Three principal components:
Original 6-band Image:
Six principal components:
|
DavinciWiki Mini-Nav Bar Contents
Contact Developers
All other topics
Recent Library Changes Created On: 02-15-2006 |
