topic Re: Using arrays to see if consecutive elements are the same in SAS Programming

Using arrays to see if consecutive elements are the same

malmario — Fri, 06 Jul 2018 20:10:47 GMT

I have a data set with the variables VentUnit1-VentUnit151,

I have been attempting to use arrays to flag observations in which VentUnit(i) in ('8N-ICU, '8S-NSICU') and VentUnit(i+1) in ('8N-ICU, '8S-NSICU') such as Line#4 in the screenshot. I'm having trouble trying to code this with do loops and have a feeling I'm taking the wrong approach.

Any thoughts?

Thanks.

Re: Using arrays to see if consecutive elements are the same

Reeza — Fri, 06 Jul 2018 20:12:07 GMT

I'm having trouble trying to code this with do loops and have a feeling I'm taking the wrong approach.

Can you show us the code you're using?

@malmario wrote:

I have a data set with the variables VentUnit1-VentUnit151,

I have been attempting to use arrays to flag observations in which VentUnit(i) in ('8N-ICU, '8S-NSICU') and VentUnit(i+1) in ('8N-ICU, '8S-NSICU') such as Line#4 in the screenshot. I'm having trouble trying to code this with do loops and have a feeling I'm taking the wrong approach.

Any thoughts?

Thanks.

Re: Using arrays to see if consecutive elements are the same

malmario — Fri, 06 Jul 2018 20:18:43 GMT

data lines5;
	set lines4;

	array Unit (*) VentUnit1-VentUnit151;

		do i=1 to i=151;
			if Unit(i) in ('8N-ICU','8S-NSICU') and Unit(i+1) in ('8N-ICU','8S-NSICU') then check+1;
		end;

run;

Re: Using arrays to see if consecutive elements are the same

Reeza — Fri, 06 Jul 2018 20:24:36 GMT

do i=1 to i=151

This is likely wrong and should be:

do i=1 to dim(unit)-1;

Because you're checking i+1 you can only go up to one less than the dimension and you can use the DIM() function to get the number of elements.

You may also want to set CHECK to 0 at the beginning of the loop but otherwise that seems correct.

data lines5;
	set lines4;

	array Unit (*) VentUnit1-VentUnit151;

check=0;

		do i=1 to dim(unit)-1;
			if Unit(i) in ('8N-ICU','8S-NSICU') and Unit(i+1) in ('8N-ICU','8S-NSICU') then check+1;
		end;

run;

Re: Using arrays to see if consecutive elements are the same

malmario — Fri, 06 Jul 2018 21:17:25 GMT

Thank you Reeza!