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Controlling the sign of eigenvectors with SLEPcEigenSolver()

0 votes

Hi,

I have a question about the eigenvalue solver 'SLEPcEigenSolver()'

For a give set of eigenvectors, will the sign be consistent?

For example, if my eigenvalues are sine waves Sin(Ax) Sin(Bx) Sin(Cx), can I be certain SLEPcEigenSolver(A,M).solve(3) will return either

{Sin(Ax) Sin(Bx) Sin(Cx)}
or
{-Sin(Ax) -Sin(Bx) -Sin(Cx)}

Or could it return a mixture of signs like

{Sin(Ax) -Sin(Bx) -Sin(Cx)}

Thanks

asked Jun 30, 2015 by sixtysymbols FEniCS User (2,280 points)
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