regarding K Map and Quine-McClusky method

[electronics_kumar]

disadvantage kmap

what is the disadvantages of K Map? I think it is suffering from some flaws so that we traversing to qQuine-McClusky method ( K Map fails when it is more than 5 variables.) My qusetion is why it is so....
it fails means what is happening in it?

 

[Kral]

disadvantages of k map

electronics_kumar,
The K map does not necessarily "fail" for higher dimensions. The problem is that it is so difficult to visualize for more than five variables. A 4 variable K-map is 2 dimenisional and easy to visualize. A 5 variable is three dimensional, but is still manageable from a visualization standpoint, because the 2 states of the 5th variable only require visually moving from one plane to the next, without moving in the x or y directions of either plane. Just getting equations correct with more than 5 variables is difficult enough using the K map, much less considering an optimum set of terms ("core" prime implicants and "choice" prime implicants).
Regards,
Kral

 

[goalied00d]

quine-mcclusky

It's harder to do by hand once you get more than 5 variables.

Like Kral stated. It's harder to visualize the third dimension and it gets confusing when working with overlapping kmaps.

Luckily there is software that can simplify for you. You enter how many variables you use and the true (or false) conditions and you'll get your new and simplified equation.

 

[mayu_wakui]

what are the drawback of karnaugh map

i might still have the software..but its dos based, so not that friendly..pm me if interested and i'll look through my old stash..

 

[rag_perfect]

mcclusky’s method.

more about digital and kmap,u can find at:
**broken link removed**

with regards;
rag_perfect

 

[goalied00d]

advantages of karnaugh map

There more updated software availible for kmapping that will run on the latest operating sytems. Plus they offer many more features than simply kmapping like outputting your original or simplified equation, using pos instead of sop for input etc.

you'll have to search google to find many of them. Some are free and some are shareware.

 

[neoaspilet11]

kmap technique

Hello Guys,
I do have a software that can do QUINE - MCCLUSKEY Algorithm but not complete yet. I made this software four years ago but i wasn't able to complete it but in my assessment its 60% complete. Its written in Visual Basic and it is highly Procedural programming. I intend to translate it to object oriented approach (still in visual basic if I can find some time) The software can solve K - map problems up to 12 variables. You don't need to visualize those 12 dimensions, All you have to do is plug in your minterms and it will automatically find the prime implicants. Thats is one step behind before you can build your SUM of PRODUCT gates.

If you anybody is interested with my software I will gladly share it, so that (you can report any bugs in it)., Just PM me.

Thanks

 

[abishek]

6 bit kmap solver

ya basically the k map is very fast for small number of variables......at the educational level

but for real time situations with many variables in a boolean expression...as someone said....the dimension keeps inc and is very tough to visualise beyond 5 variables(3D)

so there is nothing wrong with it....the algorithm is perfectly fine

 

[barkha]

k map simplify,vb 6.0

The Karnaugh Map (K-Map) based technique breaks down beyond six variables.
Quine and McCluskey proposed an algorithmic based technique for simplifying Boolean logic functions. The Quine-McCluskey (Q-M) method is a computer-based technique for simplification and has mainly two advantages over the K-Map
method. Firstly, it is systematic for producing a minimal
function that is less dependent on visual patterns.
Secondly, it is a viable scheme for handling a large number of variables.

 

[carrot]

disadvantage of kmap

Hi

K-map technique is easy to visualize and workout unitill the given function consists of less than or equal to 4 variables, but more than that ie., if it is for 5 variables then u have to go for 2^5=32boxes and do the mapping which will be very difficult. Also as the variable in a function increases the complexity of the problem increases which can be sorted quite easily with Mcclusky method.

 

[teteamigo]

5 bit kmap using 4 bit kmap

All time we learn things without "raison d'être'.

What are the principles behind K-Map?

Adjacency theorem:

x*y +x*(~y )=x

with help of Gray Code to vary one bit between all sort of input variable.

For 2,3,4,5 Maps we divide the bits of input variable to see adjacencies (varying only one bit in a word, 0->1 or 1->0)

--------------------nºplaces for each bit constant (side by side), other bits varying
For k-Map 2bit: 2
For k-Map 3bit: 4
For k-Map 4bit: 8
For k-Map 5bit: 16
For k-Map nbit: 2^(n-1)

The great difficulty is put one bit (side by side) with other bits by the same way.

The problem appears by the following way:the number of adjacencies that we have to test.

Adjacency type:

column*line

For k-Map 2bit: 2*1, 1*2
For k-Map 3bit: 2*1, 1*2, 2*2, 3*1,2*3
For k-Map 4bit: 2*1, 1*2, 2*2, 3*1,1*3,4*1,1*4,2*3,3*2, 3*4, 4*3,2*4,4*2,
For k-Map 5bit: ????

A problem: Develop a formula that accounts the nº of feasable adjacency types?

Graph theory???

 

[electronics_kumar]

related:www.asic-world.com/digital/kmaps4.html

Hello Guys,
I The software can solve K - map problems up to 12 variables. You don't need to visualize those 12 dimensions, Thanks

i found that K map will become tedious and cumbersome when number of variables is more than six ..but you are saying your solution can accomadate morethan 6 variables..how you are making your progarm to work...

 

[neoaspilet11]

5 variable map method

Yup. There is a generic algorithm that can be implemeted regardless of the number of cubes formed during adjacent minterms. I wrote the program in Visual Basic. The program calculates the adjacent minterms.

 

[A.Anand Srinivasan]

karnaugh map vs quine mccluskey

the problem is K map doesn't fail but the simplification of 6 or more variables needs us to use 3dimensional view for simplification which is hard to realise on paper

 

[maharshi_qis]

problems in quinemcclusky

ya..its limited to 6variables..afterwards its become complex..

 

[jinal patel]

quine mcclusky method to solve 6 variales

Difficult to do by hand once you get more than 5 variables.

 

[yjkwon57]

quine-mccluskey method to solve 6 variables

I think both algorithms are to be improved to guaratee the prevention of the occurrences of spikes.

 

[nanoYasser]

quine macclusky

I think that Mr.Kral is right
the K-map is avery good method to simplify comlicated expressions .. and you can feel it's benifit if you try to simplify any complex expression contains 4 variables as example using boolean algebra