A group of variables, of the same type, would be called an ARRAY. Arrays a basically only available in the data step and the definition does not persist after the data step executes. The array only operates on one observation (record or row) at a time.
In a data step you define an array using the Array statement and options.
basic definition of an array for numeric values looks like:
array somename (*) var1 var2 var3 ;
If the variable already exists it will be used, and if it doesn't then a new variable with the name is created.
If creating new variables of character type you need to provide a $ to indicate the variables are character and a length:
array something (*) $ 15 var10 var11 var12;
You can make new variables with a numeric suffix like this. Character variables would again require the $ and length.
array other (3);
Would create three variables named other1 other2 and other3.
The easiest way to use the values in an array is an iterated loop such as
do i = 1 to dim(other);
other[i] = rand('uniform');
end;
You use the index, the loop counter, to reference the elements of the array as they appear on the ARRAY statement. You can use ( ) instead of [ ] to enclose the index indicator but I find that in long lines of code it makes it easier to keep track of the index with the square brackets. The index value has to be in the range defined by the array statement. The index values must be sequential.
Advanced topics: Indices that start with a value other than 1, 2 or more dimension arrays.
There are quite a few functions that will use the whole value of the array by using the syntax (of arrayname(*) ) so that you do not have to actually loop over all the values explicitly.
The data step statistics functions like Sum, Mean, N, Nmiss and so on will use this syntax:
Total = sum(of arrayname(*) )
Many of the functions that accept varying length of variable or value lists will do this.
You can also use functions or operations that return 1) integer values 2) in the range of the index to reference elements of the array.
value = other [ i + 1];
for example.
If this is not sufficient to get you started please provide some example data of what you have in the form of a data step and what the result should look like. Example:
data have;
input x y z;
datalines;
1 2 3
1 3 17
2 2 12
;
Please paste any data step into a code box opened on the forum by using the </> icon. This is important because this forum otherwise will reformat text and may do so in a way that will prevent the data step from running. Please test your data step code before posting to make sure that it runs correctly.
If you actual problem involves many variables please use fewer to demonstrate the issue.
