{"action":"created","issue":{"url":"https://api.github.com/repos/barbagroup/PetIBM/issues/67","labels_url":"https://api.github.com/repos/barbagroup/PetIBM/issues/67/labels{/name}","comments_url":"https://api.github.com/repos/barbagroup/PetIBM/issues/67/comments","events_url":"https://api.github.com/repos/barbagroup/PetIBM/issues/67/events","html_url":"https://github.com/barbagroup/PetIBM/issues/67","id":109888236,"number":67,"title":"A is not symmetric matrix","user":{"login":"piyueh","id":7220966,"avatar_url":"https://avatars.githubusercontent.com/u/7220966?v=3","gravatar_id":"","url":"https://api.github.com/users/piyueh","html_url":"https://github.com/piyueh","followers_url":"https://api.github.com/users/piyueh/followers","following_url":"https://api.github.com/users/piyueh/following{/other_user}","gists_url":"https://api.github.com/users/piyueh/gists{/gist_id}","starred_url":"https://api.github.com/users/piyueh/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/piyueh/subscriptions","organizations_url":"https://api.github.com/users/piyueh/orgs","repos_url":"https://api.github.com/users/piyueh/repos","events_url":"https://api.github.com/users/piyueh/events{/privacy}","received_events_url":"https://api.github.com/users/piyueh/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/barbagroup/PetIBM/labels/bug","name":"bug","color":"fc2929"},{"url":"https://api.github.com/repos/barbagroup/PetIBM/labels/question","name":"question","color":"cc317c"}],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":12,"created_at":"2015-10-05T21:18:18Z","updated_at":"2015-10-07T21:43:33Z","closed_at":null,"body":"I thought A should be always symmetric after we use scaling matrices, but it turns out that, when we use non-uniform grids, it is not.  Is there a bug? or just my understanding is wrong?\r\n\r\n##### How to reproduce :\r\n\r\n(I used PETSc 3.6 + branch `AmgXSolver` and PETSc 3.5 + branch `develop`, both cases produced the same results)\r\n\r\n`mpiexec -np 1 ${PETIBM_BINARY}/petibm2d -outputs -directory ${PETIBM_EXAMPLES}/2d/lidDrivenCavity/Re100NonUniform`\r\n\r\nOpen the file `${PETIBM_EXAMPLES}/2d/lidDrivenCavity/Re100NonUniform/outputs/A.output`, and then check the extries `A(0, 31)` and `A(31, 0)`. They should have the same values, but actually they dont'."},"comment":{"url":"https://api.github.com/repos/barbagroup/PetIBM/issues/comments/146341710","html_url":"https://github.com/barbagroup/PetIBM/issues/67#issuecomment-146341710","issue_url":"https://api.github.com/repos/barbagroup/PetIBM/issues/67","id":146341710,"user":{"login":"piyueh","id":7220966,"avatar_url":"https://avatars.githubusercontent.com/u/7220966?v=3","gravatar_id":"","url":"https://api.github.com/users/piyueh","html_url":"https://github.com/piyueh","followers_url":"https://api.github.com/users/piyueh/followers","following_url":"https://api.github.com/users/piyueh/following{/other_user}","gists_url":"https://api.github.com/users/piyueh/gists{/gist_id}","starred_url":"https://api.github.com/users/piyueh/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/piyueh/subscriptions","organizations_url":"https://api.github.com/users/piyueh/orgs","repos_url":"https://api.github.com/users/piyueh/repos","events_url":"https://api.github.com/users/piyueh/events{/privacy}","received_events_url":"https://api.github.com/users/piyueh/received_events","type":"User","site_admin":false},"created_at":"2015-10-07T21:43:33Z","updated_at":"2015-10-07T21:43:33Z","body":"If A is not symmetric, and we use high-order approximation of inverse A as B (which is not implemented in our codes), will QTBNQ still be a symmetric matrix? Because I think is such case, B is not symmetric anymore."}}