topic Re: Removing a character from a macro variable in SAS Programming

Removing a character from a macro variable

hpahuja84 — Sun, 17 Jun 2018 16:28:35 GMT

Hello,

I want to remove character from macro variable. For example in below code, i want to remove character P so i am using byte(80). but

its not working and instead of P it is removing 0 . I dont want to use "P" as second argument .Only byte or hexadecimal is allowed.

%let a="p50001";

data z;
c=%sysfunc(compress(&a,byte(80)));
run;

Re: Removing a character from a macro variable

Kurt_Bremser — Sun, 17 Jun 2018 16:42:28 GMT

You are in a data step, so %sysfunc is not needed, and most probably harmful.

Re: Removing a character from a macro variable

Reeza — Sun, 17 Jun 2018 18:12:38 GMT

Byte 80 is a capital P, and your variable is lower case. Strings are case sensitive.

@hpahuja84 wrote:

Hello,

I want to remove character from macro variable. For example in below code, i want to remove character P so i am using byte(80). but

its not working and instead of P it is removing 0 . I dont want to use "P" as second argument .Only byte or hexadecimal is allowed.

%let a="p50001";

data z;
c=%sysfunc(compress(&a,byte(80)));
run;

Re: Removing a character from a macro variable

hpahuja84 — Mon, 18 Jun 2018 04:26:01 GMT

Hi Reeza,

Thanks for this.

If i use %let a="P50001"; then it is also not working.

Re: Removing a character from a macro variable

hpahuja84 — Mon, 18 Jun 2018 04:27:52 GMT

Thanks Kurt,

So is there any alternate solution for this.

Re: Removing a character from a macro variable

ChrisNZ — Mon, 18 Jun 2018 06:08:11 GMT

%let a="P50001";
data z;
  c=compress(&a,byte(80));
run;

or even better:

%let a=P50001;
data z;
  c=compress("&a",byte(80));
run;

Re: Removing a character from a macro variable

error_prone — Mon, 18 Jun 2018 06:44:31 GMT

Why byte(80) and not 'P'?

Re: Removing a character from a macro variable

Kurt_Bremser — Mon, 18 Jun 2018 06:57:10 GMT

@hpahuja84 wrote:

Thanks Kurt,

So is there any alternate solution for this.

First of all, as soon as you use the macro function %sysfunc, the whole argument inside that function turns into macro code and needs to be written as such:

%let a="P50001";

data z;
c=%sysfunc(compress(&a,%sysfunc(byte(80))));
run;

Without the inner sysfunc, the compress function will receive the string "byte(80)" as its second argument, and remove all the zeros.

And I do not see why one would use the byte() function to denote a single character, when you only have to write that character as such:

%let a=P50001;
data z;
  c=compress("&a","P");
run;

If, of course, you want to write unmaintainable obfuscated code, you should go some steps further:

%let a="P50001";

data z;
c=%sysfunc(compress(&a,%sysfunc(byte(%eval(%sysfunc(intnx(month,'01jan1960'd,2,s))+20)))));
run;

Re: Removing a character from a macro variable

Kurt_Bremser — Mon, 18 Jun 2018 06:58:11 GMT

@error_prone wrote:
Why byte(80) and not 'P'?

Exactly.

Re: Removing a character from a macro variable

hpahuja84 — Mon, 18 Jun 2018 12:05:48 GMT

Thankyou very much.

It is working now. I used byte function because in some other examples, i have to use same logic to remove non printable characters for which byte function is only needed.