help with array or macro, please?

mgrzyb — Sat, 30 Jun 2018 08:36:16 GMT

Hello,

Happy 4th of July to all of you!

This is a simple question that I used to be able to do, but can't, for the life of me, figure out. I have attached a document in WORD on how the data is displayed (it's wide longitudinal or multivariate form). I can easily transpose it to the long form.

This is what I want to do, but there has to be a simpler way. I can do this little bit now, but I will be getting more data with repeated scorings.

1. Attachment = wide form of data = the data I'm interested in is s1-s20. I am taking the difference between them at each level. I already did the proc mixed, etc. but how could I write the code (in #2) easier?

2. Here is what I need do:

data want;

set have;

d1=s2-s1;

d2=s3-s2;

d3=s4-s3;

d4=s5-s4;

d5=s6-s5;

d6=s7-s6;

d7=s8-s7;

d8=s9-s8;

d9=s10-s9;

d10=s11-s10;

d11=s12-s11;

d12=s13-s12;

d13=s14-s13;

d14=s15-s14;

d15=s16-s15;

d16=s17-s16;

d17=s18-s17;

d18=s19-s18;

d19=s20-s19;

run;

How can I do this easier? I thank you for your time. Marysia.

Re: help with array or macro, please?

FreelanceReinh — Sat, 30 Jun 2018 09:25:12 GMT

Hello Marysia,

Good idea to use arrays here (no need for macros). Indeed, this is a typical use case for arrays.

data want;
set have;
array s[20]; /* handle existing variables s1, ..., s20 as array elements s[1], ..., s[20] */
array d[19]; /* create new variables d1, ..., d19 and handle them as array elem. d[1], etc. */
do i=1 to 19;
  d[i]=s[i+1]-s[i]; /* array indices allow to compute the differences in a loop */
end;
drop i; /* index variable is no longer needed */
run;

topic Re: help with array or macro, please? in SAS Programming

help with array or macro, please?

Re: help with array or macro, please?