topic sum statement in SAS Certification

sum statement

PrinceAde — Mon, 13 Nov 2023 05:58:46 GMT

Hi everyone! Please I'm trying to figure out if the process of setting the accumulating variable in sum statement occurs at the compilation or execution phase.

The documentation reads, "the variable is automatically set to 0 before SAS reads the first observation. The variable's value is retained from one iteration to the next, as if it had appeared in a RETAIN statement." I think "before SAS reads the first observation" implies it occurred before the data step execution, i.e. at the compilation stage.

Now in the case of group processing where the accumulating variable is set to zero at the start of each BY group, this appears to be at the execution stage.

Thanks.

Re: sum statement

LinusH — Mon, 13 Nov 2023 07:07:34 GMT

I don't think this will make any practical difference.

My two cents, compilation is the process to transform your text input to executable instructions.

Setting up variables, assignments and such, for me that is part of the execution.

Re: sum statement

Kurt_Bremser — Mon, 13 Nov 2023 07:15:26 GMT

During compilation, the memory space for variables is set up, and usually initialized with missing values. Under certain circumstances, other values are used (0 through a SUM statement, or the initial values declared in a RETAIN).

Re: sum statement

LinusH — Mon, 13 Nov 2023 07:55:45 GMT

I stand corrected:

https://documentation.sas.com/doc/en/lrcon/9.4/p18vk5t9cwort1n18g7zg2no6tr4.htm

Re: sum statement

Astounding — Mon, 13 Nov 2023 07:56:42 GMT

All takes place during the compilation phase. There is no such thing as automatic changing a retained variable for a BY statement. You have to program that yourself, and it executes during the execution phase.

Re: sum statement

PrinceAde — Mon, 13 Nov 2023 08:19:37 GMT

This is very helpful. Thank you.

Re: sum statement

PrinceAde — Mon, 13 Nov 2023 08:21:11 GMT

Okay Thank you.

Re: sum statement

PrinceAde — Mon, 13 Nov 2023 08:22:18 GMT

Thank you.