Trouble with K-Map Minimizing Function: Who is Correct?

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The discussion centers on the minimization of a function using a Karnaugh Map (K-Map) and whether the book's solution is correct. Participants confirm that the book's solution is indeed equivalent to the user's result, but more efficient due to fewer AND operations. There is a debate about the proper highlighting of max 1's in the K-Map, with agreement that maximizing groups is preferable for efficiency. Ultimately, while the user's solution is functionally correct, it is deemed less efficient compared to the book's approach. The conversation emphasizes the importance of optimal grouping in K-Map minimization.
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Here is the minimize the function using K-Map given in my book
nzDkd5R.png
I have marked in red . Is that correct in book ? It seems wrong to me.Here is my solution.

R7m7vYh.png


Who is correct ?

thanks
 
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Your result is equivalent to the solution in the book since ##\bar B \bar C D\bar E + \bar B \bar C \bar D\bar E = \bar B \bar C \bar E##. I would choose the book's solution over yours since it has one less AND operation.
 
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tnich said:
Your result is equivalent to the solution in the book since ##\bar B \bar C D\bar E + \bar B \bar C \bar D\bar E = \bar B \bar C \bar E##. I would choose the book's solution over yours since it has one less AND operation.
You can not add ## \bar B \bar C \bar D\bar E## because you don't have it . Check again.
 
momentum said:
You can not add ## \bar B \bar C \bar D\bar E## because you don't have it . Check again.
You must be looking at a different diagram than the one you posted. The one I see has ##1##s in the squares for ##B=C=D=E=0##. You don't seem to have any argument with the ## \bar B \bar C \bar D## term since you have it in your solution. But ## \bar B \bar C \bar D + \bar B \bar C \bar D\bar E = \bar B \bar C \bar D##, so you can add ##\bar B \bar C \bar D\bar E## to your solution to get an equivalent form.
 
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I see it. It's circled even though it's enclosed in one of the groups of four probably to emphasize it.
 
tnich said:
The one I see has ##1##s in the squares for ##B=C=D=E=0##.

I don't see it. Can you please circle it in different color in my diagram ?

tnich said:
But ## \bar B \bar C \bar D + \bar B \bar C \bar D\bar E = \bar B \bar C \bar D##

How ?
 
Joshy said:
I see it. It's circled even though it's enclosed in one of the groups of four probably to emphasize it.
could you please mark in a different color in diagram . I don't see it.
 
momentum said:
I don't see it. Can you please circle it in different color in my diagram ?
Circled in blue
Kdiagram.png
 
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momentum said:
How ?
##\bar B \bar C \bar D+\bar B \bar C \bar D\bar E=\bar B \bar C \bar D(1+\bar E)=\bar B \bar C \bar D(1)=\bar B \bar C \bar D##
 
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tnich said:
##\bar B \bar C \bar D+\bar B \bar C \bar D\bar E=\bar B \bar C \bar D(1+\bar E)=\bar B \bar C \bar D(1)=\bar B \bar C \bar D##

Okay. got it ... that works.

But in diagram in general , we should highlight max 1's in K-Map. ...right ? we should not be using Single 1s ( blue circle which you marked) if the max 1s is available ...am I right ?

my Solution is also correct ...right ?
 
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  • #11
momentum said:
my Solution is also correct ...right ?
Functionally, yes. Maximally efficient, no. Leans a little bit in the direction of using a shotgun to kill a fly. :wink:
 
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  • #12
momentum said:
But in diagram in general , we should highlight max 1's in K-Map. ...right ? we should not be using Single 1s ( blue circle which you marked) if the max 1s is available ...am I right ?
Yes, you are right, and that has been the point all along.
$$\begin{align}&\bar D \bar E+ \bar B \bar C \bar D + && \bar ACDE + BCD+\bar B\bar CD\bar E\nonumber\\
=&\bar D \bar E+ \bar B \bar C \bar D+\bar B \bar C \bar D \bar E + && \bar ACDE + BCD+\bar B\bar CD\bar E\nonumber\\
=&\bar D \bar E+ \bar B \bar C \bar D + && \bar ACDE + BCD+\bar B\bar CD\bar E+\bar B \bar C \bar D \bar E\nonumber\\
=&\bar D \bar E+ \bar B \bar C \bar D + && \bar ACDE + BCD+\bar B\bar C\bar E\nonumber\end{align}$$
replaces ##\bar B\bar CD\bar E## with ##\bar B\bar C\bar E## giving a more efficient form.
 
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