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Student Support Forum: 'mutual information of red andgreen channel of a...' topicStudent Support Forum > General > "mutual information of red andgreen channel of a..."

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matt prior
09/21/07 10:09am

Hi there


I think you could adopt one of two approaches.

The first and probably the most practical is to replace the histogram entries that are zero with
the smallest machine precision number.
So after you calculate the histograms but before you calculate the mutual information... do

histRed = histRed /. 0 -> $MachineEpsilon
histGreen = histGreen /. 0 -> $MachineEpsilon


The other approach would be to split the calculation of the second part of the mutual information from:=

Log[ P(x,y)/(p(x) p(y))]

Into ...
Log[p(x,y)] - Log[p(x) p(y)]

This removes the division by zero ... but leaves you with an infinite probability .. which is theoretically correct but perhaps not that useful.

Hope that helps,
Matt


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Subject (listing for 'mutual information of red andgreen channel of a...')
Author Date Posted
mutual information of red andgreen channel of a... Matther Fergie 09/17/07 5:16pm
Re: mutual information of red andgreen channel ... yehuda ben-s... 09/18/07 2:08pm
Re: mutual information of red andgreen channel ... matt prior 09/21/07 10:09am
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