topic Re: SAS Code Help - What am I doing wrong? in SAS Programming

SAS Code Help - What am I doing wrong?

aroux — Thu, 17 Sep 2015 05:56:46 GMT

I am just learning SAS. I am doing a simple problem for a statistics class using SAS 9.4 and have run into a problem that I do not understand the error message and how to resolve the error. The proble is to create an inverse of a matrix.

The following is the code I used:

proc iml;

A={1 2, 2 -2, 3 10};

B=A`;

print A B;

run;

AB=A*B;

print AB;

run;

invAB=inv(AB);

print invAB;

run;

The following is the error message that I am receiving:

1 proc iml;

NOTE: Writing HTML Body file: sashtml.htm

NOTE: IML Ready

2 A={1 2, 2 -2, 3 10};

3 B=A`;

4 print A B;

5 run;

NOTE: Module MAIN is undefined in IML; cannot be RUN.

7 AB=A*B;

8 print AB;

9 run;

NOTE: Module MAIN is undefined in IML; cannot be RUN.

11 invAB=inv(AB);

ERROR: (execution) Matrix should be non-singular.

operation : INV at line 11 column 10

operands : AB

AB 3 rows 3 cols (numeric)

5 -2 23

-2 8 -14

23 -14 109

statement : ASSIGN at line 11 column 1

12 print invAB;

ERROR: Matrix invAB has not been set to a value.

statement : PRINT at line 12 column 1

13 run;

NOTE: Module MAIN is undefined in IML; cannot be RUN.

I am using code that was supplied by the instructor (which worked). I changed nothing with the instructor's code, but can not get a resolution. What am I doing wrong?

Thank you for your help

Thank you for your assistance.

Re: SAS Code Help - What am I doing wrong?

arodriguez — Thu, 17 Sep 2015 06:24:54 GMT

If I'm not mistaken, the determinant of the matrix is equal to 0, so it can not be inverted

Re: SAS Code Help - What am I doing wrong?

Kurt_Bremser — Thu, 17 Sep 2015 06:27:45 GMT

The error with INV is described here: http://support.sas.com/documentation/cdl/en/imlug/63541/HTML/default/viewer.htm#imlug_langref_sect158.htm

You need to define modules in IML before you can RUN them, this causes the notes.

I don't know if it is good to dive into IML when you are just starting out with learning SAS, but you should at least take a thorough look at the SAS/IML documentation (SAS/IML Overview).

Re: SAS Code Help - What am I doing wrong?

Ksharp — Fri, 18 Sep 2015 06:48:10 GMT

As LOG pointed out. Your matrix is singular. Such kind of matrix can't a inverse . ERROR: (execution) Matrix should be non-singular. And You'd better post it at IML forum, since it is IML code. And you don't need RUN in IML, but need a QUIT at the end of IML code.