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How to log transform a text file?


 
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# 1  
Old 10-14-2011
How to log transform a text file?

How can I log transform (log 2) a text file which is a single column of numbers?
# 2  
Old 10-14-2011
You've asked this question about a million times before and instead of clarifying what you want, you just keep making more threads asking the same thing.
# 3  
Old 10-14-2011
Basically I have a text file that is a single column with numbers:


895.851565910482
899.387944585978
890.325878026497
891.721527294983
884.747806845593
874.704995010979

I want to log 2 transform it. What is the function that I should use?
# 4  
Old 10-14-2011
I'll take a wild guess and say log. But that's likely to be log e, not log 2. Easy conversion though, just divide by log e(n) to get log n.
Code:
awk '{ $1=log($1)/log(2) } 1' < infile > outfile

This User Gave Thanks to Corona688 For This Post:
# 5  
Old 10-14-2011
What language - C is one with a log2() function ready to use.
 

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