Sum of digits calculation – Pitney Bowes J640 User Manual

Page 79

Advertising
background image

Sum of Digits Calculation –––––––––––––––––––––––––––––––––––

This is an example of how the printer uses Sum of Digits to
calculate a check digit for this data:

5 2 3 2 4 5 2 1 9

1. Weights are applied to each digit, starting with the last

digit in the weight string. They are applied right to left,
beginning at the right-most position of the field.
Remember, a weight string must contain at least two
different numbers. This example has a weight string
of 1,2,3,4.

field:

5 2 3 2 4 5 2 1 9

weight string:

4 1 2 3 4 1 2 3 4

2. Each digit in the field is multiplied by the weight assigned

to it:

field:

5 2 3 2 4 5 2 1 9

weight string:

4 1 2 3 4 1 2 3 4

products:

20 2 6 6 16 5 4 3 36

3. Next, the digits of the products are added together.

Two-digit products are treated as two separate digits.
This is the sum of the digits.

2 + 0 + 2 + 6 + 6 + 1 + 6 + 5 + 4 + 3 + 3 + 6 = 44

Usin

g

Ch

eck Dig

it

s

Chapter 3. Using Check Digits

3-5

Advertising
This manual is related to the following products: