topic Re: SAS function PROD not working in SAS Programming

SAS function PROD not working

iank131 — Sat, 04 Feb 2017 10:17:07 GMT

Hi,

Here's a real easy problem. It could be due to my PC SAS version 9.4 running Windows 7.

I am trying to multiply all the elements of a vector using SAS function PROD, but it is giving me an error "ERROR 68-185: The function PROD is unknown, or cannot be accessed." The vector may include missing values. The idea is very similar to SAS function SUM, which ignores missing values and sums all the values of the vector.

For example:

data _null_;
a = prod(2, 1, ., 3);
put "a equals " a;
run;

But then I get the error. If instead of "prod" I write "sum", there is no error.

Is there something wrong with my base SAS? Do other people have the same problem? What am I doing wrong?

Re: SAS function PROD not working

Peter_C — Sat, 04 Feb 2017 11:18:47 GMT

I expect you should be using PROD() in SAS/IML

Re: SAS function PROD not working

iank131 — Sat, 04 Feb 2017 11:31:07 GMT

SUM() is also SAS/IML but it works in base SAS. I am wondering why PROD() does not work in base SAS, or if is there an equivalent such function? Thanks.

Re: SAS function PROD not working

PeterClemmensen — Sat, 04 Feb 2017 11:44:32 GMT

So in a product context, you want your missing values to be treated like a 1 right?

Re: SAS function PROD not working

Kurt_Bremser — Sat, 04 Feb 2017 11:45:49 GMT

PROD() was introduced with SAS/IML, much later than the SUM() function that has been in Base SAS as long as I can remember (SAS 6.09).

It seems nobody ever had a real need for such a function in Base.

You might put it up as a ballot idea.

Re: SAS function PROD not working

iank131 — Sat, 04 Feb 2017 15:33:13 GMT

Yes. Or just ignore missing values.

Re: SAS function PROD not working

Tom — Sun, 05 Feb 2017 13:05:32 GMT

There is not a PROD() function in BASE SAS. But if your numbers are positive then you might be able to use GEOMEAN() function instead. Example:

data have ;
  input a1-a4 ;
cards;
2 1 . 3
1 1 1 1
10 10 10 10
;
data want ;
  set have;
  array x a1-a4 ;
  prod1 = 1;
  do i=1 to dim(x);
    prod1=prod1*coalesce(x(i),1);
  end;
  prod2=geomean(of x(*))**n(of x(*));
  put (_all_) (=);
run;