Date:         Thu, 17 Jul 1997 09:38:19 -0500
Reply-To:     jon@spss.com
Sender:       "SPSSX(r) Discussion" <SPSSX-L@UGA.CC.UGA.EDU>
From:         Jonathan Fry <jon@SPSS.COM>
Organization: SPSS Inc.
Subject:      Re: Repeat commands
Content-Type: text/plain; charset=us-ascii

DUCATI 750 SuperSport wrote:
>
> Hi,
>
> I have a set to variable rt1 to rt36. I like to subtract from every third
> variable the precceding two, e.g.
>
> compute diff1 = rt3 - rt1.
> compute diff2 = rt3 - rt2.
> compute diff3 = rt6 - rt4.
> compute diff4 = rt6 - rt5.
>
> I tried to use the loop - end loop command, but no avail. Does somebody know
a
> solution? Otherwise, I have to use the inelegant approach of typing all
> substractions I need.
>
> met hartelijke groeten
>
> Jens Boelte
> -------------------------------
> Psychologisches Institut II
> Fliedner Str. 21
> 48149 Muenster
> Germany
 
--
Assuming you have 36 rt variables which are consecutive in your file,
and want 24 differences, you could use
 
        vector rt (rt1 to rt36).
        vector diff (24)
        loop #i = 0 to 11.
            compute diff(2*#i+1) = rt(3*#i+3) - rt(3*#i+1).
            compute diff(2*#i+2) = rt(3*#i+3) - rt(3*#i+2).
        end loop.
--------------------
Jonathan Fry
SPSS Inc.
jon@spss.com