sum statement

[PrinceAde]

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.

[LinusH]

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.

[Kurt_Bremser · Accepted solution]

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).

[LinusH]

I stand corrected:

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

[PrinceAde]

This is very helpful. Thank you.

[PrinceAde]

Thank you.

[Astounding]

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.

[PrinceAde]

Okay Thank you.