topic Re: Calling a user-written function within a user-written function gives wrong result in SAS Programming

Calling a user-written function within a user-written function gives wrong result

AndrewJones — Fri, 11 Jun 2021 16:45:23 GMT

Hello,

I am using the following code:

proc fcmp outlib = work.functions.testing;
function getfirstPercentage(agency $, sbwe_agencies $);
pc = 0;
if index(sbwe_agencies,agency)>0
	then do;
			pc = 1;
		end;
return(pc);
endsub;

function getSecondPercentage(agency $, sbwe_agencies $);
co = getfirstPercentage(agency, sbwe_agencies);
return(co);
endsub;

quit;

options cmplib=(work.functions);

data test;
	sbwe_agencies = "BSCV904,BSCV905,BSCV908,SBCV135,SBCV136,SBCV137";
	agency = "SBCV136";
	firstPercentage = getfirstPercentage(agency , sbwe_agencies);
	SecondPercentage = getSecondPercentage(agency , sbwe_agencies);
	put firstPercentage= SecondPercentage=;
run;

The function getSecondPercentage calls getFirstPercentage, so I would expect FirstPercentage and SecondPercentage to both return 1. However, I get this

52         data test;
53         	sbwe_agencies = "BSCV904,BSCV905,BSCV908,SBCV135,SBCV136,SBCV137";
54         	agency = "SBCV136";
55         	firstPercentage = getfirstPercentage(agency , sbwe_agencies);
56         	SecondPercentage = getSecondPercentage(agency , sbwe_agencies);
57         	put firstPercentage= SecondPercentage=;
58         run;

firstPercentage=1 SecondPercentage=0

Why doesn't SecondPercentage return 1 as well? How do I need to do to get SecondPercentage to return 1? Is there a way to debug a user-written function?

Thanks for any help

Andrew

Re: Calling a user-written function within a user-written function gives wrong result

ballardw — Fri, 11 Jun 2021 17:34:23 GMT

Try

function getfirstPercentage(agency $, sbwe_agencies $);
pc = 0;
if index(sbwe_agencies,STRIP(agency))>0
	then do;
			pc = 1;
		end;
return(pc);
endsub;

I think what is happening is the way the Second passes the value to first is defaulting to a length that includes trailing blanks and those are used in the second call.

This is analogous to some of the other character operations in SAS.

Here is an example with the || operator and Index functions:

data example;
   length v $ 10;
   v='abc';
   q= '"'||v||'"';
   put q=;
   z = index('123abc',v);
   put z=;
run;

The log will show:

q="abc       "
z=0

because the full length is used in both the concatenation and the Index function.

Re: Calling a user-written function within a user-written function gives wrong result

AndrewJones — Fri, 11 Jun 2021 18:27:09 GMT

@ballardw

You are a genius and a life saver. I know about trailing blanks, but they still catch me out.

Thanks you for taking the time to sort this out for me

Andrew