Re^5: Calculate log of matrix values

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.

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Comment on Re^5: Calculate log of matrix values Download Code

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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]