topic Re: Using reference data in a sas program in SAS Programming

Using reference data in a sas program

Danduke22 — Thu, 07 Dec 2023 12:07:36 GMT

I have some reference data that I've imported from a csv file.

Then using a data step 1 - I've then stored them in arrays.

I've then create a new data step 2 based around some transactions using macros but when I try to reference the arrays created in data step 1 it is not recognising them.

What is the best solution to overcome this scenario

Your help would be greatly appreciated!

Re: Using reference data in a sas program

PaigeMiller — Thu, 07 Dec 2023 12:18:42 GMT

Data step #2 does not know about arrays created in data step #1. You would have to define the same arrays in data step #2 in order to work with arrays in data step #2.

Re: Using reference data in a sas program

Tom — Thu, 07 Dec 2023 14:15:41 GMT

An ARRAY is just a convenient way to reference a series of variables using an index. They only exist for the step where they are defined. Any variables you create using references to elements of an array will exist but the concept of an array will not.

If you need the DATA generated in the first data step then include that data as input to the second data step.

But I suspect that you just need one data step.

Lets assume your REFERENCE dataset has 40 observations of a variable named VALUE. And your real data, let's call it HAVE, has a variable named INDEX with values from 1 to 40 and you want to use that to lookup the the right value for REFERENCE. In that case your single data step might look like this:

data want;
  if _n_=1 then do;
      array ref [40]  _temporary_;
      do i=1 to 40;
         set reference ;
         ref[i] = value;
      end;
  end;
  set have;
  if index in (1:40) then value=ref[index];
  else value=.;
run;

Re: Using reference data in a sas program

Patrick — Thu, 07 Dec 2023 14:26:24 GMT

You would need to provide a bit more detail of how this reference data looks like and how you want to use it.

SAS Arrays are just a way to address individual variables within a data step. They don't persist over data step boundaries.

You can also use hash lookups (hash tables) to lookup values over a key.

You can use a data step merge or a SQL join to add reference data to a base table.

The one thing that you can store permanently are key/value pairs in the form of a SAS format (proc format cntlin= ). Once the format has been created you can use it in any data step and also in procedures.

Re: Using reference data in a sas program

ballardw — Thu, 07 Dec 2023 15:37:59 GMT

Can you provide a small example of HOW you are using the reference data?

If the "reference" data is used to look up things, example product number to product name, price or description then using that data to make a Format may be more flexible approach than actually combining data sets and manipulation.

@Danduke22 wrote:

I have some reference data that I've imported from a csv file.

Then using a data step 1 - I've then stored them in arrays.

I've then create a new data step 2 based around some transactions using macros but when I try to reference the arrays created in data step 1 it is not recognising them.

What is the best solution to overcome this scenario

Your help would be greatly appreciated!