topic Re: sum function in SAS in New SAS User

sum function in SAS

frakje — Tue, 07 Jan 2020 08:59:59 GMT

Hello

One simple question.

I want to calculate the sum of a variable in my long formatet dataset.

My dataset looks like this:

ID gmfcs_dummy

1000 0

1000 1

2000 0

3000 1

I want to calculate the sum of gmfcs_dummy so it sums up in rising order like this:

ID gmfcs_dummy gmfcs_dummy2

1000 1 1

1000 1 2

2000 0 0

3000 1 1

3000 1 2

3000 1 3

How can I do this?

Kind regards Frank

Re: sum function in SAS

ed_sas_member — Tue, 07 Jan 2020 08:04:03 GMT

Hi @frakje

You can use this:

data have;
	input ID gmfcs_dummy;
	datalines;
1000 0
1000 1
1000 1
1000 0
2000 0
2000 0
2000 0
3000 1
3000 1
3000 1
;
run;

data want;
	set have;
	by ID;
	if first.ID then gmfcs_dummy2 = 0;
	if gmfcs_dummy=1 then gmfcs_dummy2 + gmfcs_dummy;
	else gmfcs_dummy2 = 0;
run;

Re: sum function in SAS

Kurt_Bremser — Tue, 07 Jan 2020 08:33:39 GMT

@frakje wrote:

Hello

One simple question.

I want to calculate the sum of a variable in my long formatet dataset.

My dataset looks like this:

ID        gmfcs_dummy

1000    0

1000    1

1000    1

2000    0

2000    0

2000    0

3000    1

3000    1

3000    1

I want to calculate the sum of gmfcs_dummy so it count upwise like this:

ID         gmfcs_dummy   gmfcs_dummy2

1000            1                       1

1000            1                       2

2000            0                       0

2000           0                       0

2000            0                       0

3000           1                        1

3000           1                        2

3000           1                        3

How can I do this?

Kind regards Frank

Why does your intended result contain only 2 observations for ID 1000, but 3 for ID 2000?

Re: sum function in SAS

frakje — Tue, 07 Jan 2020 08:39:42 GMT

Hallo Kurt

It's because the observations/patients has an new treatment every year. Each patient can have different entry dates in the follow-up program.

Patient with ID 1000 have e.g. first treatment in 2016, second treatment in 2017 and third treatment in 2018. Therefore there is three records for that specific patient.

Re: sum function in SAS

Kurt_Bremser — Tue, 07 Jan 2020 09:04:09 GMT

But 1000 has only 2 (TWO) observations in your result.

Re: sum function in SAS

frakje — Tue, 07 Jan 2020 09:07:29 GMT

Oh, sorry!

Typing error. It should have been three

Re: sum function in SAS

Kurt_Bremser — Tue, 07 Jan 2020 09:15:13 GMT

Then try this:

data want;
set have;
by id;
if first.id
then gmfcs_dummy2 = gmfcs_dummy;
else gmfcs_dummy2 + gmfcs_dummy;
run;