topic Re: roundoff errors result in an asymmetric error in IML? in SAS Programming https://communities.sas.com/t5/SAS-Programming/roundoff-errors-result-in-an-asymmetric-error-in-IML/m-p/119525#M293385 <HTML><HEAD></HEAD><BODY><P>You will probably get a quicker answer if you post this to the IML forum.&nbsp; The folks there are very good.</P><P></P><P>Steve Denham</P></BODY></HTML> Thu, 08 Nov 2012 16:05:31 GMT SteveDenham 2012-11-08T16:05:31Z roundoff errors result in an asymmetric error in IML? https://communities.sas.com/t5/SAS-Programming/roundoff-errors-result-in-an-asymmetric-error-in-IML/m-p/119524#M293384 <HTML><HEAD></HEAD><BODY><P>A matrix(V) is supposed to be symmetric, but eventually it potentially departs from an symmetric marix. I checked the iteration steps. It looks the matrix gradually departs an symmetric matrix. Do roundoff errors result in the asymmetric matrix in IML?</P><P></P><P>At each step, I corrected the matrix by setting V=(V+V`)/2. Does it make sense? What else can I use to modify the program?</P><P></P><P>Thanks for your help in advance!!</P></BODY></HTML> Wed, 07 Nov 2012 15:45:14 GMT https://communities.sas.com/t5/SAS-Programming/roundoff-errors-result-in-an-asymmetric-error-in-IML/m-p/119524#M293384 renc 2012-11-07T15:45:14Z Re: roundoff errors result in an asymmetric error in IML? https://communities.sas.com/t5/SAS-Programming/roundoff-errors-result-in-an-asymmetric-error-in-IML/m-p/119525#M293385 <HTML><HEAD></HEAD><BODY><P>You will probably get a quicker answer if you post this to the IML forum.&nbsp; The folks there are very good.</P><P></P><P>Steve Denham</P></BODY></HTML> Thu, 08 Nov 2012 16:05:31 GMT https://communities.sas.com/t5/SAS-Programming/roundoff-errors-result-in-an-asymmetric-error-in-IML/m-p/119525#M293385 SteveDenham 2012-11-08T16:05:31Z