How can calculate compression ratio in Principal component analysis using SVD

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Noor Abbas
Noor Abbas 2017-9-18
评论： Walter Roberson 2017-9-20
compression ratio is the rate of original file on the compressed file. but in PCA tech the ratio= 1024/(2*PrinComps+1)?

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Image Analyst
Image Analyst 2017-9-18
I don't understand the question. Compression ratio is the ratio of the disk size of the original (uncompressed) image divided by the size of the compressed image file. Like if the original file was 10 MB and you compressed it, what whatever method (SVD or otherwise), and now the size of the compressed file is 2 MB, then the compression ratio is 10/5 = 5 to 1. So, is that formula not working for you?
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Noor Abbas
Noor Abbas 2017-9-20
thanks for your answers, but my question is how can i calculate compression ratio in PCA (principal component analysis)code
Walter Roberson
Walter Roberson 2017-9-20
I showed how to use whos to find out the data storage requirement of a matrix. Call that on the original matrix. Call that on each of the matrices of non-constant values that are needed together to reconstruct the original matrix, and sum those. The original size divided by the sum of the representation matrix sizes is the compression ratio.

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Noor Abbas
Noor Abbas 2017-9-18
please see the code

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