Re^4: Calculate log of matrix values

I did misunderstand your intention. However I still do not understand your solution. If I assume that the zero data is really a small positive number that displays as '0.00', its log should be a negative number whose magnatude exceeds any of the other logs. (e.g. log(0.001) = -6.9) Setting the log to zero assumes that the raw value is e (2.71...). Note: All other values are between .001 (log(.01) = -4.6) and .99 (log(.99) = -.01).

Bill

Comment on Re^4: Calculate log of matrix values

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Re^5: Calculate log of matrix values by BrowserUk (Patriarch) on Aug 09, 2013 at 20:08 UTC
Setting the log to zero ... I didn't suggest setting the log to zero. Or mention doing anything to the logs. its log should be a negative number whose magnatude exceeds any of the other logs. And if you set values that are 0(.00000) to 1e-308, then when their logs are taken, they become `say log(1e-308);; -709.196208642166` [download] which fulfills your "negative number whose magnatude exceeds any of the other logs." in spades. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply] [d/l]
Re^6: Calculate log of matrix values by BillKSmith (Monsignor) on Aug 10, 2013 at 18:51 UTC
What a difference a day makes. Of course it is an excelent idea to replace the zero in the raw data with a small number (Especially if there is reason to believe that the zero is the result of truncation.) Bill	[reply]