Why Does this Array Code Add a Column Named 'i'???

[d6k5d3]

I have the following code to run an array:

data HUF_Speech;
set HUF_Speech;

array  SP{66} SP1-SP66;
do i=1 to 66;
if SP{i}=. then SP{i}=0;
end;
run;

Initially there were 83 columns, but surprisingly, after running the code above, a column 'i' is added which has '67' as a value in all rows! How can this be possible?

Much thanks.

Regards.

[PGStats · Accepted solution]

No magic here. Variable i is created as the control variable of the do loop. You can add the statement

drop i;

anywhere within the datastep to prevent variable i from being kept in the results.

[d6k5d3]

Does this always happen with arrays?

[PGStats]

It is not created by the array. It happens with all do loop control variables.

for example

data test;
do i = 1 to 4;
    output;
    end;
run;

creates a dataset with a single variable: i.

[d6k5d3]

Thank you! 🙂