View Issue Details
| ID | Project | Category | View Status | Date Submitted | Last Update |
|---|---|---|---|---|---|
| 0000715 | OpenFOAM | Bug | public | 2013-01-02 14:24 | 2013-01-02 17:09 |
| Reporter | michele | Assigned To | |||
| Priority | normal | Severity | minor | Reproducibility | have not tried |
| Status | resolved | Resolution | fixed | ||
| Platform | Linux | OS | OpenSuse | OS Version | 11.3 |
| Summary | 0000715: wrong SVD outputs, for certain matrix configurations | ||||
| Description | I encountered wrong outputs of the SVD decomposition, that occur on some particular input matrix configurations. | ||||
| Steps To Reproduce | Here attached a simple test, run: wmake; SVDtest The output is uncorrect (wrong U, S, V and pseudoinverse). Here below the wrong output produced by the program: U(A) : 3 3((0 -0.457702 0.889106)(-0.361655 -0.828924 -0.426721)(0.932312 -0.321549 -0.16553)) S(A) : 3(758.049 281.274 808.55) V(A) : 3 3((-1 0 0)(-0 -0.932312 0.361655)(-0 -0.361655 -0.932312)) pseudoinverse(A) : 3 3((0 0.000477086 -0.00122988)(0.00191479 0.00255669 0.000991769)(-0.000436698 0.00155785 0.000604307)) If line 35 is commented, and line 36 is uncommented out (the vector F has just one less digit, so the output should be essentially the same) and the test is re-run, the output is now correct; for instance the pseudoinverse: pseudoinverse(A) : 3 3((-9.85333e-10 0.000419348 -0.00108105)(-0.000419351 7.28519e-10 0.000430246)(0.00108105 -0.000430245 2.56813e-10)) is confirmed by matlab (whose output is practically identical for both cases): pinv(A) -8.6139e-20 4.1935e-04 -1.0810e-03 -4.1935e-04 -2.7105e-20 4.3025e-04 1.0810e-03 -4.3025e-04 -1.0842e-19 | ||||
| Tags | No tags attached. | ||||
| Date Modified | Username | Field | Change |
|---|---|---|---|
| 2013-01-02 14:24 | michele | New Issue | |
| 2013-01-02 14:24 | michele | File Added: SVDtest.tar.gz | |
| 2013-01-02 15:41 |
|
Assigned To | => user17 |
| 2013-01-02 15:41 |
|
Status | new => assigned |
| 2013-01-02 17:09 |
|
Note Added: 0001852 | |
| 2013-01-02 17:09 |
|
Status | assigned => resolved |
| 2013-01-02 17:09 |
|
Fixed in Version | => 2.1.x |
| 2013-01-02 17:09 |
|
Resolution | open => fixed |
