# RE: st: RE: summing up digits and comparing to a check digit

 From "Nick Cox" To Subject RE: st: RE: summing up digits and comparing to a check digit Date Wed, 15 Mar 2006 15:43:11 -0000

```It's on SSC, as indicated. But I suspect Michael
Blasnik has solved your problem directly.

Nick
n.j.cox@durham.ac.uk

Lia Orfei

> wow the very author - thanks - if only I could find the program!

Nick Cox

> >-pnrcheck- from SSC covers the Swedish case.
> >
> >In this case, look _inside_ the program
> >for some ideas. String functions are not
> >the only way. -mod()- is also useful.
> >
> >The authors of -pnrcheck- are two Italians
> >and a Welshman, just who you would expect
> >to be working on Swedish identifiers.

Lia Orfei

> >>I have a variable that contains 7-digit numbers; the first
> >>digit is the
> >>remainder of the sum of the last six digits divided by 10
> >>(check digit)
> >>
> >>example: 1030332 => 0+3+0+3+3+2=11/10=1+1 => check digit=1
> >>              12050457 => 0+5+0+4+5+7=21/10=2+1 => check digit=1
> >>and so on.
> >>
> >>Now I want to assess whther the check digit is correct for
> each entry.
> >>
> >>How do I calculate the partial sum of the contents of this variable?
> >>
> >>Extra challenge: some of the numbers sum up to 10, 20 etc so
> >>the check
> >>digit is actually 0 and it does not appear in the data for
> >>some reason
> >>(example 50456 is correct becasue 5+0+4+5+6=20 so the
> remainder is 0).
> >>
> >>Any ideas?? I was thinking about using the string functions.

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