Thank you Han and Nick, I agree, splitting the blocks would work too. It's not hard to do, and Leonids workaround is even easier. I should be able to make it work.
Thank you all for your quick and great suggestions! Philip On July 6, 2023 10:39:50 PM ADT, "郑晗" <han.zh...@drugchina.net> wrote: >Hi Philip, > >In my opinion, each block of the omega matrix should be a positive-definite >matrix. This is because the omega matrix serves as a variance-covariate >matrix. However, any block matrix that contains zeros on the diagonal would >not qualify as a positive-definite matrix. > >However, there is one exception to this rule. The block matrix with diagonal >intentionally fixed to zero allows for the convenient removal of IIV/IOV >without altering the index of eta/omega. I think splitting the omega matrix >into two block matrix is a good idea, although it is probally more difficult >to generate programmatically. > >Best wishes, > >Han > >___________________________ > >郑晗 博士 >Han Zheng, M.D., Ph.D. > >北京博之音科技有限公司 Beijing BioVoice Technology Co., Ltd. >上海博佳医药科技有限公司 Shanghai BioGuider Medical Technology Co., Ltd. >地址：上海市 浦东新区 祖冲之路 2277弄世和商务中心 1号楼501室 邮编201203 >Address: 1-501 Shihe Business Center, No. 2277 Zuchongzhi Road, Pudong New >District, Shanghai 201203 >Mb: 156 1895 5099，E-mail: han.zh...@drugchina.net > >本邮件（或含附件）中包含法律规定的机密，特许或享有版权的信息，该信息只提供给上述指定的人员或机构使用。如果您非指定收件方，您必须知道任何全部或部分的对本邮件（或附件）进行使用，复制或授权他人使用均是被严格禁止的。如果您误收到此邮件，请告知发件人并退回且在您的系统中删除该邮件所有信息。 >This e-mail with attachments is for use by the intended recipient and contains >information that may be confidential, privileged or copyrighted under >applicable law. If you are not the intended recipient, you are here formally >notified that any use, copying or distribution of this e-mail or attachments, >in whole or in part, is strictly prohibited. Please notify the sender by >return and delete the e-mail from your system > >On 6 July 2023 at 6:08:14 pm, Philip Harder Delff (phi...@delff.dk) wrote: > >Hi all, > >I am trying to specify a full OMEGA matrix for simulation purpose. I get >issues because some diagonals are zero and some are positive. If I write > >$OMEGA BLOCK(3) FIX >0.078 >0 0.02 >0 0 0 > >I get this error: >AN ERROR WAS FOUND ON LINE 34 AT THE APPROXIMATE POSITION NOTED: >0 0 0 > >224 A VARIANCE IS ZERO, BUT THE BLOCK IS NOT FIXED TO ZERO. > >I know I could do: >$OMEGA BLOCK(2) FIX >0.078 >0 0.02 >$OMEGA FIX >0 > >However, that would be complicated to generate programmatically. Anyway >I can tell Nonmem to use a specified OMEGA matrix as is for a >simulation? > >Thank you, >Philip >
