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Wrong Results

Wrong results from LAPACK routines are most often caused by incorrect usage.

It is also possible that wrong results are caused by a bug outside of LAPACK, in the compiler or in one of the library routines, such as the BLAS, that are linked with LAPACK. Test procedures are available for both LAPACK and the BLAS, and the LAPACK installation guide [3] should be consulted for descriptions of the tests and for advice on resolving problems.

A list of known problems, compiler errors, and bugs in LAPACK routines is maintained on netlib; see Chapter 1.

Users who suspect they have found a new bug in an LAPACK routine are encouraged to report it promptly to the developers as directed in Chapter 1. The bug report should include a test case, a description of the problem and expected results, and the actions, if any, that the user has already taken to fix the bug.

Susan Blackford