NONMEM Users Network Archive

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R MATRIX ALGORITHMICALLY SINGULAR

From: Hudachek,Susan <Susan.Hudachek>
Date: Wed, 9 Sep 2009 18:33:47 -0600

Greetings! I have run several models and the covariance steps have been uns=
uccessful due to the following error:

R MATRIX ALGORITHMICALLY SINGULAR
COVARIANCE MATRIX UNOBTAINABLE
R MATRIX IS OUTPUT
T MATRIX - EQUAL TO RS*R, WHERE S* IS THE INVERSE OF S - IS OUTPUT

Does anyone have an idea as to what this indicates and how to 'fix" it? Tha=
nks in advance for any help/input you can offer!
Susan

Susan Hudachek, M.S., Ph.D.
Animal Cancer Center
Veterinary Teaching Hospital
Colorado State University
300 West Drake Road
Fort Collins, CO 80523-1620
PHONE: (970) 219-7599
FAX: (970) 297-1254
EMAIL: Susan.Hudachek
Received on Wed Sep 09 2009 - 20:33:47 EDT

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