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Topic: strange booleanconvert behavior?
Replies: 2   Last Post: Jul 11, 2012 2:18 AM

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 Francisco Gutierrez Posts: 102 Registered: 5/31/05
strange booleanconvert behavior?
Posted: Jul 10, 2012 12:42 AM

Dear Group:
Say I have the following expression:
num1={{a,b,c,d},{a,b,c,e},{a,b,c,f},{a,b,c,g},{a,b,c,h},{a,b,c,i},{a,b,c,j},{a,b,c,k},{a,b,c,l},{a,b,c,m},{a,b,c,n}}

I transform it into a logical expression:
n=
um2=Apply[Or,Apply[And,#]&/@num1]

I want to simplify this to a CNF, and the obvious function to use is Boolean Convert. Suppose I apply it to NINE elements of num2:
BooleanConvert[Take[num2,9],"CNF"]
The output is
a&&b&&c&&(d||e||f||g||h||i||j||k||l)

It works perfectly well!

However, if I apply BooleanConvert to the whole expression I get back a bunch of crap. Also if I apply it to 10 elements of num2.
In sum, it appears that BooleanConvert only works well for 9 expressions or less. Tried this with other two examples, and found
exactly the same result.

All this in Mathematica 8

Can somebody help me?
Francisco

Date Subject Author
7/10/12 Francisco Gutierrez
7/11/12 Peter Pein
7/11/12 Peter Pein