Sum of digits calculation – Pitney Bowes J640 User Manual
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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
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Chapter 3. Using Check Digits
3-5