Date:         Tue, 3 Dec 2002 09:26:14 +1100
Reply-To:     Simon Freidin <s.freidin@iaesr.unimelb.edu.au>
Sender:       "SPSSX(r) Discussion" <SPSSX-L@LISTSERV.UGA.EDU>
From:         Simon Freidin <s.freidin@iaesr.unimelb.edu.au>
Subject:      Re: String variables:  breaking a list into it's parts
Comments: To: "Johnson, Wendy SBCCOM(N)" <Wendy.Johnson@natick.army.mil>
In-Reply-To:  <8AE0F8238A85D94A97151B5462C8BA7F4061C9@natickexch02.natick.army.mil>
Content-type: text/plain; charset="us-ascii"; format=flowed

At 01:06 PM 12/2/2002 -0500, Johnson, Wendy SBCCOM(N) wrote:
>Hello,
>
>I often have open-ended responses in my data sets, including lists of
>items separated by commas, like so:
>What I want is to find out how many times each item was mentioned.  To do
>this, I've come up with some syntax which will take a list and break it
>down into individual items (see below).  Basically it works, but I have to
>know (or guess) the greatest
>number of items in any given list.  This will never be the case.  Any
>suggestions (or general comments) would be greatly appreciated.


set printback=listing mxwarns=0.
data list list (tab)/id (f4) list (a80).
begin data
2341    skittles
3333    cheese, peanut butter
4213    beef curry, green eggs and ham, skittles
1125    cigarettes, beverage base, m&ms, gatorade, twix
1238    gum, peanuts, grape juice, coffee, potato chips
end data.
execute.

/* write data out so can read back comma delimited (up to 1000 30-char
items per case) */
write outfile='c:\temp\list.txt'/id ',' list.
execute.
data list file='c:\temp\list.txt' list (",")/id (f4) item1 to item1000
(1000a30).
execute.

/* write out individual items (if they exist) comma delimited */
do repeat x=item1 to item1000.
do if x ne ''.
write outfile='c:\temp\list2.txt'/id ',' x.
end if.
end repeat.
execute.

/* read individual items */
data list file='c:\temp\list2.txt' list (",")/id (f4) item (a30).
execute.
/* strip space prefixes and set to lower case (or use upcase if you prefer) */
if substr(item,1,1)=' ' item=substr(item,2).
compute item=lower(item).

freq vars=item.


Research Database Manager and Analyst
Melbourne Institute of Applied Economic and Social Research
The University of Melbourne
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