2 Transformations with 1 IF statement?

[ariel barak]

Hello All,

I've got program start dates for individuals and need to match their corresponding assessments according to whether the
assessment was done during certain time frames - start date to start date + 180 days, start date + 181 days to start
date + 360 days, etc. My real data has 4 time periods where assessment scores need to be placed. What I would like to
do is to use an IF statement to push through two transformations instead of one.

If the assessment date was between the start date in the program and 180 day after the program start, I would like:

1) AssessDate180=assessdate.1   AND
2) AssessScore180=assessscore.1

In otherwords, is there a way to combine the last two IF statements into one statement?

Thanks,
Ariel

Please see the data below.

DATA LIST LIST /client_no (F8) startdate (ADATE10) startdate180 (ADATE10)
assessdate.1 (ADATE10) assessscore.1 (F8.0).
BEGIN DATA
3442    7/8/2009 1/4/2010 8/12/2009 65
1217    12/19/2009 6/17/2010 7/3/2010 78
5916    1/5/2009 7/4/2009 1/8/2009 92
END DATA.

COMPUTE AssessDate180=0.
COMPUTE AssessScore180=0.

RECODE AssessDate180 AssessScore180 (0=SYSMIS).
EXECUTE.

FORMATS AssessDate180 (ADATE10).

IF (assessdate.1>=startdate) AND (assessdate.1<startdate180) AssessDate180=assessdate.1.
IF (assessdate.1>=startdate) AND (assessdate.1<startdate180) AssessScore180=assessscore.1.
EXECUTE.

[Gerard van Meurs-2]

Hi Ariel,

 

Yes, there is: the do if ... end if-construct.

 

DO IF (assessdate.1>=startdate) AND (assessdate.1<startdate180).

compute AssessDate180=assessdate.1.

compute AssessScore180=assessscore.1.

END IF.

EXECUTE.

 

 

Kind regards,

 

Gerard van Meurs

---

Van: SPSSX(r) Discussion [mailto:[hidden email]] Namens Ariel Barak
Verzonden: vrijdag 20 mei 2011 16:19
Aan: [hidden email]
Onderwerp: 2 Transformations with 1 IF statement?

 

Hello All,

I've got program start dates for individuals and need to match their corresponding assessments according to whether the
assessment was done during certain time frames - start date to start date + 180 days, start date + 181 days to start
date + 360 days, etc. My real data has 4 time periods where assessment scores need to be placed. What I would like to
do is to use an IF statement to push through two transformations instead of one.

If the assessment date was between the start date in the program and 180 day after the program start, I would like:

1) AssessDate180=assessdate.1   AND
2) AssessScore180=assessscore.1

In otherwords, is there a way to combine the last two IF statements into one statement?

Thanks,
Ariel

Please see the data below.

DATA LIST LIST /client_no (F8) startdate (ADATE10) startdate180 (ADATE10)
assessdate.1 (ADATE10) assessscore.1 (F8.0).
BEGIN DATA
3442    7/8/2009 1/4/2010 8/12/2009 65
1217    12/19/2009 6/17/2010 7/3/2010 78
5916    1/5/2009 7/4/2009 1/8/2009 92
END DATA.

COMPUTE AssessDate180=0.
COMPUTE AssessScore180=0.

RECODE AssessDate180 AssessScore180 (0=SYSMIS).
EXECUTE.

FORMATS AssessDate180 (ADATE10).

IF (assessdate.1>=startdate) AND (assessdate.1<startdate180) AssessDate180=assessdate.1.
IF (assessdate.1>=startdate) AND (assessdate.1<startdate180) AssessScore180=assessscore.1.
EXECUTE.

[Maguin, Eugene]

Ariel,

 

No. You are applying the same test to two different variables. Two lines of code is as short as you can get.

 

If you were willing to write three lines of code you could use a Do repeat structure like this

 

do repeat y=AssessDate180 AssessScore180/x=assessdate.1 assessscore.1.

if (assessdate.1>=startdate) AND (assessdate.1<startdate180) compute x=y.
end repeat.

 

Gene Maguin

 

---

From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf Of Ariel Barak
Sent: Friday, May 20, 2011 10:19 AM
To: [hidden email]
Subject: 2 Transformations with 1 IF statement?

Hello All,

I've got program start dates for individuals and need to match their corresponding assessments according to whether the
assessment was done during certain time frames - start date to start date + 180 days, start date + 181 days to start
date + 360 days, etc. My real data has 4 time periods where assessment scores need to be placed. What I would like to
do is to use an IF statement to push through two transformations instead of one.

If the assessment date was between the start date in the program and 180 day after the program start, I would like:

1) AssessDate180=assessdate.1   AND
2) AssessScore180=assessscore.1

In otherwords, is there a way to combine the last two IF statements into one statement?

Thanks,
Ariel

Please see the data below.

DATA LIST LIST /client_no (F8) startdate (ADATE10) startdate180 (ADATE10)
assessdate.1 (ADATE10) assessscore.1 (F8.0).
BEGIN DATA
3442    7/8/2009 1/4/2010 8/12/2009 65
1217    12/19/2009 6/17/2010 7/3/2010 78
5916    1/5/2009 7/4/2009 1/8/2009 92
END DATA.

COMPUTE AssessDate180=0.
COMPUTE AssessScore180=0.

RECODE AssessDate180 AssessScore180 (0=SYSMIS).
EXECUTE.

FORMATS AssessDate180 (ADATE10).

IF (assessdate.1>=startdate) AND (assessdate.1<startdate180) AssessDate180=assessdate.1.
IF (assessdate.1>=startdate) AND (assessdate.1<startdate180) AssessScore180=assessscore.1.
EXECUTE.

[Richard Ristow]

At 10:19 AM 5/20/2011, Ariel Barak wrote:

>If the assessment date was between the start date in the program and
>180 day after the program start, I would like:
>
>1) AssessDate180=assessdate.1   AND
>2) AssessScore180=assessscore.1
>
>In otherwords, is there a way to combine the last two IF statements
>into one statement?
>...
>IF (assessdate.1>=startdate) AND (assessdate.1<startdate180)
>     AssessDate180=assessdate.1.
>IF (assessdate.1>=startdate) AND (assessdate.1<startdate180)
>     AssessScore180=assessscore.1.

Of the two solutions posted, the DO IF will be the faster, possibly
by enough to matter, since it tests the date value only once, not
twice. (There've been several postings about slow code that appeared
to be caused by its containing a great many IF tests.)

It sounds like your actual code will have tests for not just 1-180
days, but a set of intervals. A reasonably fast and readable version
might look like this:

COMPUTE DaysSinceStart = CTIME.DAYS(assessdate.-startdate).

DO IF   RANGE(DaysSinceStart,  1,180).
.  COMPUTE AssessDate180=assessdate.1
.  COMPUTE AssessScore180=assessscore.1.
ELSE IF RANGE(DaysSinceStart,181,360).
.  COMPUTE AssessDate360=assessdate.1.
.  COMPUTE AssessScore360=assessscore.1.
ELSE IF RANGE(DaysSinceStart,361,540).
...
END IF.

Or, you could very fast but, perhaps, less readable code, by making
the AssessDatexxx and AssessScorexxx variables elements of two
vectors, and writing something like this (untested):

COMPUTE DaysSinceStart = CTIME.DAYS(assessdate.-startdate).
COMPUTE #Interval      = TRUNC(DaysSinceStart)/180.
COMPUTE

COMPUTE AssessDate(#Interval) =assessdate.1
COMPUTE AssessScore(#Interval)=assessscore.1.

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[ariel barak]

Thanks everyone. I think the DO IF RANGE approach is the way to go.

Thanks again,
Ariel

On Tue, May 24, 2011 at 3:33 PM, Richard Ristow <[hidden email]> wrote:

At 10:19 AM 5/20/2011, Ariel Barak wrote:

If the assessment date was between the start date in the program and 180 day after the program start, I would like:

1) AssessDate180=assessdate.1   AND
2) AssessScore180=assessscore.1

In otherwords, is there a way to combine the last two IF statements into one statement?

...

IF (assessdate.1>=startdate) AND (assessdate.1<startdate180)
   AssessDate180=assessdate.1.
IF (assessdate.1>=startdate) AND (assessdate.1<startdate180)
   AssessScore180=assessscore.1.

Of the two solutions posted, the DO IF will be the faster, possibly by enough to matter, since it tests the date value only once, not twice. (There've been several postings about slow code that appeared to be caused by its containing a great many IF tests.)

It sounds like your actual code will have tests for not just 1-180 days, but a set of intervals. A reasonably fast and readable version might look like this:

COMPUTE DaysSinceStart = CTIME.DAYS(assessdate.-startdate).

DO IF   RANGE(DaysSinceStart,  1,180).
.  COMPUTE AssessDate180=assessdate.1
.  COMPUTE AssessScore180=assessscore.1.
ELSE IF RANGE(DaysSinceStart,181,360).
.  COMPUTE AssessDate360=assessdate.1.
.  COMPUTE AssessScore360=assessscore.1.
ELSE IF RANGE(DaysSinceStart,361,540).
...
END IF.

Or, you could very fast but, perhaps, less readable code, by making the AssessDatexxx and AssessScorexxx variables elements of two vectors, and writing something like this (untested):

COMPUTE DaysSinceStart = CTIME.DAYS(assessdate.-startdate).
COMPUTE #Interval      = TRUNC(DaysSinceStart)/180.
COMPUTE

COMPUTE AssessDate(#Interval) =assessdate.1
COMPUTE AssessScore(#Interval)=assessscore.1.