topic Re: Creating new variable in SAS Procedures

Creating new variable

sks521 — Tue, 18 Jun 2019 13:32:29 GMT

I want to create a new variable from an existing variable.

The existing variable has following values- GP, AHP, HCA, Nurse, admin

I want to create a new variable which does not include 'admin' and missing values, and coded '1' for all other values (GP, AHP, HCA, Nurse).

I have written the following syntax but it's giving '.' for all values in the new variable.

Can someone help please?

Thanks

Re: Creating new variable

sks521 — Tue, 18 Jun 2019 13:39:40 GMT

Sorry forgot to post the syntax;

if professionalcontact=. then visit=.;
else if professionalcontact in ('Admin', 'unkno') then delete;*this gives 11520 observations/visits;
else if professionalcontact in ('GP', 'AHP', 'HCA', 'Nurse') then visit=1;

Re: Creating new variable

Cynthia_sas — Tue, 18 Jun 2019 13:47:31 GMT

Hi:

The first thing I would do is run a PROC FREQ on the input data set to find out what values _EXACTLY_ are in the field or variable PROFESSIONALCONTACT -- to check case, length, etc. Then you would be able to tell whether the number deleted by your IF statement was correct.

Cynthia

Re: Creating new variable

tsap — Tue, 18 Jun 2019 13:50:30 GMT

If possible, can you provide the logic to create a dummy data set that aligns with the dataset you are working to manipulate?

Use the instructions on this page to help, https://communities.sas.com/t5/SAS-Communities-Library/How-to-create-a-data-step-version-of-your-data-AKA-generate/ta-p/258712 .

That would give a better starting point for us to understand what the starting data looks like and how the logic you are using afterwards is interacting with it.

Thanks

Re: Creating new variable

sks521 — Tue, 18 Jun 2019 13:51:20 GMT

Hi Thanks, here is the freq proc;

The FREQ Procedure

ProfessionalContact Frequency Percent CumulativeFrequency CumulativePercentAHPAdminGPHCANurseUnknoFrequency Missing = 1

660	3.58	660	3.58
6923	37.54	7583	41.12
8147	44.18	15730	85.29
68	0.37	15798	85.66
1925	10.44	17723	96.10
719	3.90	18442	100.00

Re: Creating new variable

sks521 — Tue, 18 Jun 2019 13:54:54 GMT

Sorry it changed the format a little bit;

Each value in the left column represent number for each of the following categories;

AHP

Admin

HCA

Nurse

Unkno

Re: Creating new variable

sks521 — Tue, 18 Jun 2019 14:48:24 GMT

And here is snapshot of the the new variable 'visit' created from existing variable 'professionalcontact'

PKid ProfessionalContact visit

.		.
1	GP	.
1	Nurse	.
1	Nurse	.
1	Admin	.
1	GP	.
1	Admin	.
1	Admin	.
1	GP	.
1	GP	.

Re: Creating new variable

Kurt_Bremser — Tue, 18 Jun 2019 15:00:27 GMT

@sks521 wrote:

Sorry forgot to post the syntax;

if professionalcontact=. then visit=.;
else if professionalcontact in ('Admin', 'unkno') then delete;*this gives 11520 observations/visits;
else if professionalcontact in ('GP', 'AHP', 'HCA', 'Nurse') then visit=1;

The dot represents missing numeric values, but you work with character variables. Use an empty string ("") to represent missing character values.

Since your first use of the new variable was numeric, it was defined as such, and all attempts to assign character values to it will result in missing values, and NOTEs with ERRORs and finally a WARNING.

Before you expand this if/then/else chain, take a look at the data step select statement (not the SQL one).

Re: Creating new variable

sks521 — Tue, 18 Jun 2019 15:02:33 GMT

Thanks for helping but I couldn't get 'Before you expand this if/then/else chain, take a look at the data step select statement (not the SQL one).'. Can you elaborate further please?

Re: Creating new variable

Kurt_Bremser — Tue, 18 Jun 2019 15:14:08 GMT

Look at this example for your logic:

select (professionalcontact);
  when ('') visit = .;
  when ('Admin', 'unkno') delete;
  when ('GP', 'AHP', 'HCA', 'Nurse') visit = 1;
  otherwise; /* if you omit this, you will be alerted to an unexpected value by an ERROR */
end;

I just noted that you actually want to have a numeric value in visit, so ignore that part of my previous post.

Re: Creating new variable

sks521 — Tue, 18 Jun 2019 15:15:37 GMT

Very helpful indeed! thanks for all your help