Gray codes in Karnaugh maps

Question

In my textbook, they have given some applications of Gray codes. One use of Gray code is in Karnaugh maps.

Here Gray codes are used, but why is the decimal equivalent of binary code written in that box instead of the decimal equivalent of Gray code? That is, first row, third column box should be written as 2, right? Since 011 is Gray code, its decimal value is 2. Please clarify this.

Answer 1

The definition of the outputs shown within a karnaugh map is defined by a forumla or truth table, of which the axis values are the inputs. In this example, 0 1 2 ... has apparently been used as arbitrary filler numbers.

Gray codes refer only to the method by which the axis are labeled.

Here are some clear examples of how the tables are used.