K V Charts in Software Testing Methodologies

If the expressions in four, five, or six variables are used, it will be more confused and also leads to many errors designing test cases there are bugs in the routine which is testing

Karnaugh Veith chart reduces boolean algebraic manipulations to graphical details

Beyond six variables these diagrams get cumbersome (weight) and may not be effective

Single Variable

Two Variables

Three Variables

Four Variables and More

Single Variable:

Image  shows all the boolean functions of a single variable and their and their equivalent representation as

KV chart

The charts show all possible truth values that the variable A can have

A "1" means the variable's value is "1" or TRUE. A "0" means that variables value is 0 or FALSE

The entry in the box (0 or 1) specifies is true or false for that value of the variable

Do not explicitly put in 0 entries but specify only the conditions under which the function is true

Two Variables:

Image shows eight of the sixteen possible functions of two variables

Each box corresponds to the combination of values of the variables for the row and column of that box

A pair may be adjacent either horizontally or vertically but not diagonally

Any variable that changes in either the horizontal or vertical direction does not appear in the expression

In the fifth chart, the B variable changes from 0 to 1 going down the column, and because the A variables value for column is 1, the chart is equivalent to simple A

Three Variables:

Image shows KV charts for three variables
As before, each box represents an elementary term of three variables with a bar appearing according to whether the row-column heading for that box is 0 or 1
A three variable chart can have grouping of 1, 2, 4 and 8 boxes
A few examples will illustrate the principles
Notice that there are several ways to circle the boxes into maximum sized covering groups

Four Variables and More:                                    

A for variable KV Chart and other possible adjacencies is shown in the image
Adjacencies can now consist of 1,2,4,8 and 16 boxes and the terms resulting will have 4,3,2,1 and 0's in them respectively

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About Data Sciences by Venu

Hi, My name is Venugopala Chary and I'm Currently working as Associate Professor in Reputed Engineerng College, Hyderabad. I have B.Tech and M.tech in regular from JNTU Hyderabad. I have 11 Years of Teaching Experience for both B.Tech and M.Tech Courses.