You can read the other posts about mod() as a remainder, but assuming you need mod 7 as in "base 7" or like base 2 (binary) this should verify that a number does indeed fit the "base 7" form

function VerifyBase7(tcNumber)
return not('7' $ tcNumber or '8' $ tcNumber or '9' $ tcNumber)


>Does the way MOD() (or "mod 7") works is the digits must be 6 (via, 123456) or it must have a character and then 6 digits (via, A123456)? So, is the correct way to check/verfiy it is (this formula is for with a character and then 6 digits):
>
>STORE SUBSTR(num,2,5) TO no
>STORE MOD(VAL(no),7) TO chk
>IF SUBSTR(STR(chk),10,1) = SUBSTR((no,7,1)
>
>ELSE
>
>ENDIF
>
>Is that correct? I am puzzled with my supervisor saying it is the 4 digits, but the old program that I am looking uses 5 digits. I am all new to this. I never learned "mod 7" before.
>
>Chuck

If they have you asking the wrong questions,
they don't have to worry about the answers.
-proverbs for paranoids #3