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### [Lapack] Non-orthogonal eigenvectors from DSYEVR

 ```Hi, For your information: For some matrices DSYEVR, when told to compute a small number of eigenvalues, returns non-orthogonal eigenvectors. Perhaps it possible for the algorithm to detect this and return with an error? This applies at least when using the automatically chosen ABSTOL. However, at least for the example below, I wasn't able to find a suitable ABSTOL for which it would work. Maybe, this might have to do with the fact that for the example problem below, the first eigenvalue is multiply degenerate, and the numerical second eigenvalue is eps-close to the first one. The following test program illustrates this: http://projects.scipy.org/scipy/raw-attachment/ticket/1159/test.f90 with the test data http://projects.scipy.org/scipy/raw-attachment/ticket/1159/L.txt On Lapack 3.2.1 + reference BLAS, I get: \$ gfortran -o test test.f90 -llapack -lblas \$ ./test < L.txt orth error ( 2 eigs): -0.96599125529927221 HUGE ERROR orth error ( 3 eigs): -0.96599125529927232 HUGE ERROR orth error ( 4 eigs): -0.96599125529927221 HUGE ERROR orth error ( 5 eigs): -2.52928802610462387E-017 orth error ( 6 eigs): -1.47893223140021721E-016 orth error ( 7 eigs): -1.18177613284446356E-016 orth error ( 8 eigs): 0.0000000000000000 orth error ( 9 eigs): -2.84549495443531079E-016 orth error ( 10 eigs): -2.93456682158620488E-016 ```
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