# does the order of the rows matter? [closed]

from my understanding the truth table is supposed to generate every possible combination of true and false values without the order of the combination taking into account.

however one of my teachers said that their is a particular order to each row that is used to generate multiple combinations.

can you please explain this to me.

• Your understanding is correct. However, can you think of any way in which your teacher might make sense? – John L. Feb 4 '19 at 16:00
• I don't understand your question. Are you just asking if it matters what order the rows of a truth table are written in? – David Richerby Feb 4 '19 at 16:10
• @DavidRicherby yes – Abdullah Mustapha Feb 4 '19 at 16:42
• The order of the row don’t matter, as long as you cover every possible combination of input values. Doing this without an order in mind, does not make it incorrect, but it does make it easier to miss some entries. I think your prof is suggesting using a order so you cover all the combinations in a systemic way. What I do, if I have N Boolean inputs for example, I start with the first row have all values assumed false. In the next row, I make the Nth bool true, then only the N-1 true, then both N and N-1 true, then N-2 true with N and N-1 false, and so on. Any such system is fine. – ScottK Feb 4 '19 at 16:50
• @ScottK Summary: you order the rows to be the binary representation of the numbers $0, \dots, 2^N-1$. – David Richerby Feb 4 '19 at 16:53

"@ScottK Summary: you order the rows to be the binary representation of the numbers $$0, \dots, 2^N-1$$. " -@DavidRicherby