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How to use PROC FREQ to count characters under one variable

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Occasional Contributor
Posts: 6

How to use PROC FREQ to count characters under one variable

Hello!

 

I need to get frequencies for a number of different symptoms experienced by patients in a data set. The problem is that they are all listed under the same variable: Symptoms and each column under it has a different string of letters depending on what the patient presented with.

 

Symptoms

C

C, A

W, A

C, W, A

W, R, V

 

I have been able to count the single letters but not all of the "C"'s "W"'s etc. 

 

Is there an easy way to do this?

 

Thanks!

PROC Star
Posts: 7,366

Re: How to use PROC FREQ to count characters under one variable

Here is one way:

 

data have;
  informat Symptoms $50.;
  input Symptoms &;
  cards;
C
C, A
W, A
C, W, A
W, R, V
;

data need;
  set have;
  _n_=1;
  do while (scan(Symptoms,_n_,',') ne '');
    symptom=scan(Symptoms,_n_,',');
    output;
    _n_+1;
  end;
run;

proc freq data=need;
  tables symptom;
run;

HTH,

Art, CEO, AnalystFinder.com

 

Valued Guide
Posts: 797

Re: How to use PROC FREQ to count characters under one variable

You need to loop over each individual symptom in symptons.  Output each of the individuals, and then run proc freq:

 

 

data have;
  input symptoms $8.;
datalines;
C
C, A
W, A
C, W, A
W, R, V
run;

data vhave/ view=vhave;
  set have;
  length symptom $1.;
  do I=1 to countw(symptoms,',');
    symptom= left(scan(symptoms,I,','));
	output;
  end;
run;
proc freq data=vhave;
  tables symptom;
run;
Super User
Posts: 9,691

Re: How to use PROC FREQ to count characters under one variable

Better post the output you need too .

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